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1. 123 APPENDIX A ALPHABETICAL LISTING OF COMMAND LINE OPTIONS 2 h lt lt Op PHEI5DDCZECO Show errors default 0 Show nothing except errors Show warnings u Show unit info Show notes t Show tried used files Show hints E Show conditionals Show general info d Show debug info Show linenumbers Y Rhide GCC compatibility mode Show everything x Executable info Win32 only Write file names messages with full path Write fpcdebug txt with p Write tree log with parse tree lots of debugging info Executable options Pass shared dynamic to the linker BeOS Darwin FreeBSD Linux Do not use standard library search path needed for cross compile Use external linker Create debuginfo in a separate file and add a debuglink section to Try to link units dynamically defines FPC_LINK_DYNAMIC Use internal linker Generate link map Set the name of the main program routine default is main Prepend the binutils names with the prefix lt x gt Set library search path to lt x gt needed for cross compile BeOS Li Prepend lt x gt to all linker search paths BeOS Darwin FreeBSD Linu Strip all symbols from executable Try to link units statically default defines FPC_LINK_STATIC Link with static libraries static is passed to linker Try to smartlink units defines FPC_LINK_SMART Show this help Shows this help without waiting 124 Appendix B Alphabetical
2. In the above example usr lib fpc 2 2 0 linuxunits will be added to the path if you re NOT compil ing with version 2 2 0 of the compiler 5 2 3 ELSE Syntax ELSE ELSE can be specified after a IFDEF or IFNDEF directive as an alternative Lines following ELSE are read only if the preceding IFDEF or IFNDEF was not accepted They are skipped until the keyword ENDIF is encountered after which normal processing is re sumed Example IFDEF VER2_2_2 Fu usr lib fpc 2 2 2 linuxunits ELSE Fu usr lib fpc 2 2 0 linuxunits ENDIF In the above example usr lib fpc 2 2 2 linuxunits will be added to the path if you re compiling with version 2 2 2 of the compiler otherwise usr lib fpc 2 2 0 linuxunits will be added to the path 5 2 4 ENDIF Syntax ENDIF E between EA op ENDIF marks the end of a block that started with IF N DEF possibly with an E them 32 CHAPTER 5 COMPILER CONFIGURATION 5 2 5 DEFINE Syntax DEFINE name DEF INE defines a new keyword This has the same effect as a dname command line option 5 2 6 UNDEF Syntax UNDEF name UNDEF un defines a keyword if it existed This has the same effect as a uname command line option 5 2 7 WRITE Syntax WRITE Message Text WRITE writes Message
3. Error ENDIF without IF N DEF Your SIFDEF and ENDIF statements aren t balanced Fatal User defined arg1 A user defined fatal error occurred See also the Programmers guide Error User defined arg1 A user defined error occurred See also the Programmers guide Warning User defined arg1 A user defined warning occurred See also the Programmers guide Note User defined arg1 A user defined note was encountered See also the Programmers guide Hint User defined arg1 A user defined hint was encountered See also the Programmers guide Info User defined arg1 User defined information was encountered See also the Programmers guide Error Keyword redefined as macro has no effect You cannot redefine keywords with macros 128 APPENDIX C COMPILER MESSAGES Fatal Macro buffer overflow while reading or expanding a macro Your macro or its result was too long for the compiler Warning Expanding of macros exceeds a depth of 16 When expanding a macro macros have been nested to a level of 16 The compiler will expand no further since this may be a sign that recursion is used Warning compiler switches aren t supported in styled comments Compiler switches should be in normal Pascal style comments Handling switch arg1 When you set debugging info on vd the compiler tells you when it is evaluating conditional compile statements ENDIF arg1 found When you turn on conditional messages vc the compiler tells yo
4. 2 In Free Pascal you can use the function return value in the function itself as a variable For example 91 CHAPTER 7 PORTING AND PORTABLE CODE function a longint begin a 12 while a gt 4 do begin deco end end The example above would work with TP but the compiler would assume that the a gt 4 is a recursive call If a recursive call is actually what is desired you must append after the function name function a longint begin a 12 this is the recursive call if a gt 4 then begin ia end end In Free Pascal there is partial support of Delphi constructs See the Programmers guide for more information on this The Free Pascal exit call accepts a return value for functions function a longint begin a 12 if a gt 4 then begin exit a 67 function result upon exit is ax67 end end Free Pascal supports function overloading That is you can define many functions with the same name but with different arguments For example procedure DoSomething a longint begin Camat end procedure DoSomething a real begin EN end You can then call procedure DoSomething with an argument of type Longint or Real This feature has the consequence that a previously declared function must always be defined with the header completely the same 92 CHAPTER 7 PORTING AND PORTABLE CODE T procedure x v longint forward era procedure x This will
5. e The Windows unit provides access to most of the core Win32 API Some calls may have dif ferent parameter lists instead of declaring a parameter as passed by reference var a pointer is used as in C For most cases Free Pascal provides overloaded versions of such calls e Widestrings Widestring management is not automatic in Free Pascal since various platforms have different ways of dealing with widestring encodings and Multi Byte Character Sets FPC supports Widestrings but may not use the same encoding as on Windows Note that in order to have correct widestring management you need to include the cwstring unit on Unix LINUX platforms This unit initializes the widestring manager with the necessary callbacks which use the C library to implement all needed widestring functionality e Threads At this moment Free Pascal does not offer native thread management on all plat forms on Unix linking to the C library is needed to provide thread management in an FPC application This means that a cthreads unit must be included to enable threads e A much quoted example is the Set LastOSError call This is not supported and will never be supported Filename Case sensitivity Pascal is a case insensitive language so the uses clause should also be case insensitive Free Pascal ensures case insensitive filenames by also searching for a lowercase version of the file Kylix does not do this so this could create problems if two differently
6. e The option inbytab means indent by a tab e The option upper uppercase the keyword else or Else becomes ELSE Try to play with the configfile step by step until you find the effect you desire The configurability and possibilities of ptop are quite large E g I like all keywords uppercased instead of capitalized so I replaced all capital keywords in the default file by upper ptop is still development software So it is wise to visually check the generated source and try to compile it to see if ptop hasn t introduced any errors 8 8 3 ptopu unit The source of the PtoP program is conveniently split in two files one is a unit containing an object that does the actual beautifying of the source the other is a shell built around this object so it can be used from the command line This design makes it possible to include the object in a program e g an IDE and use its features to format code The object resides in the PtoPU unit and is declared as follows TPrettyPrinter Object TObject 107 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL Indent Integer How many characters to indent Ins PStream Outs PStream DiagS PStream CfgS PStream Constructor Create Function PrettyPrint Boolean end Using this object is very simple The procedure is as follows 1 Create the object using its constructor 2 Set the InS stream This is an open stream from which Pascal source will be read Th
7. would return myfile NAMEEXTO Replaced by the name and extension part of the filename argument e g SNAMEEXT d data myfile pas would return myfile pas NOSWAP Does nothing in the IDE it is provided only for compatibility with Turbo Pascal PROMPT Prompt displays a dialog box that allows editing of all arguments that come after it Arguments that appear before the PROMPT keyword are not presented for editing SPROMPT can also take an optional filename argument If present SPROMPT will load a dialog description from the filename argument E g SPROMPT cvsco tdf would parse the file cvsco tdf construct a dialog with it and display it After the dialog closed the information entered by the user is used to construct the tool command line See section 6 10 7 page 65 for more information on how to create a dialog description SAVE Before executing the command the active editor window is saved even if it is not modified SAVE_ALL Before executing the command all unsaved editor files are saved without prompting SAVE_CUR Before executing the command the contents of the active editor window are saved without prompting if they are modified SAVE_PROMPT Before executing the command a dialog is displayed asking whether any un saved files should be saved before executing the command WRITEMSG Writes the parsed tool output information to a file with name as in the argument 64 Remark
8. At least 80 MB free disk space When the sources are installed another 270 MB are needed 2 1 2 Software requirements Under DOS The DOS distribution contains all the files you need to run the compiler and compile Pascal programs Under UNIX Under UNIX systems such as LINUX you need to have the following programs installed 10 CHAPTER 2 INSTALLING THE COMPILER 1 GNU as the GNU assembler 2 GNU ld the GNU linker 3 Optionally but highly recommended GNU make For easy recompiling of the compiler and Run Time Library this is needed Under Windows The WINDOWS distributions both 32 and 64 bit contain all the files you need to run the compiler and compile Pascal programs However it may be a good idea to install the mingw32 tools or the cygwin development tools Links to both of these tools can be found on http www freePascal org Under OS 2 While the Free Pascal distribution comes with all necessary tools it is a good idea to install the EMX extender in order to compile and run programs with the Free Pascal compiler The EMX extender can be found on http www leo org pub comp os os2 leo gnu emxtgec index html Under Mac OS X Mac OS X 10 1 or higher is required and the developer tools or XCode should be installed 2 2 Installing the compiler The installation of Free Pascal is easy but is platform dependent We discuss the process for each platform separately 2 2 1 Installing under Windows
9. Error The type of the storage symbol must be boolean If you specify a storage symbol in a prop erty declaration it must be a boolean type Error This symbol isn t allowed as storage symbol You can t use this type of symbol as storage specifier in property declaration You can use only methods with the result type boolean boolean class fields or boolean constants Error Only classes which are compiled in M mode can be published A class typed field in the published section of a class can only be a class which was compiled in M or which is de rived from such a class Normally such a class should be derived from TPersistent Error Procedure directive expected This error is triggered when you have a Calling di rective without a calling convention specified It also happens when declaring a procedure in a const block and you used a after a procedure declaration which must be followed by a procedure directive Correct declarations are 140 APPENDIX C COMPILER MESSAGES const p procedure stdcall nil p procedure stdcall nil Error The value for a property index must be of an ordinal type The value you use to index a property must be of an ordinal type for example an integer or enumerated type Error Procedure name too short to be exported The length of the procedure function name must be at least 2 characters long This is because of a bug in dlltool which doesn t parse the def file correct
10. Error function header arg1 doesn t match forward var name changes arg2 gt arg3 You de clared the function in the interface part or with the forward directive but defined it with a different parameter list Note Values in enumeration types have to be ascending Free Pascal allows enumeration construc tions as in C Examine the following two declarations A_A A_B A_ A_A A_B A_ 6 A_UAS 200 6 A_UAS 4 type a type a The second declaration would produce an error A_UAS needs to have a value higher than A_E ie at least 7 Error With can not be used for variables in a different segment With stores a variable locally on the stack but this is not possible if the variable belongs to another segment Error function nesting gt 31 You can nest function definitions only 31 levels deep Error range check error while evaluating constants The constants are out of their allowed range Warning range check error while evaluating constants The constants are out of their allowed range Error duplicate case label You are specifying the same label 2 times in a case statement Error Upper bound of case range is less than lower bound The upper bound of a case label is less than the lower bound and this is useless Error typed constants of classes or interfaces are not allowed You cannot declare a constant of type class or object Error functions variables of overloaded functions are not allowed You are try
11. Assembler info When writing assembler files this option decides which extra information is written to the assembler file in comments List source The source lines are written to the assembler files together with the generated assembler a1 on the command line List register allocation The compiler s internal register allocation deallocation information is written to the assembler file ar on the command line List temp allocation The temporary register allocation deallocation is written to the assem bler file at on the command line List node allocation The node allocation deallocation is written to the assembler file Tan on the command line use pipe with assembler use a pipe on unix systems when feeding the assembler code to an external assembler 73 CHAPTER 6 THE IDE Figure 6 27 The browser options tab Compiler Suitches Browser Browser 5 No browser The latter three of these options are mainly useful for debugging the compiler itself it should rarely be necessary to use these Assembler output This option tells the compiler what assembler output should be generated Use default output This depends on the target Use GNU as Assemble using GNU as Aas on the command line Use NASM coff Produce NASM coff assembler go32v2 Anasmcoff on the command line Use NASM elf Produce NASM elf assembler LINUX Anasme1 on the command line Use NASM obj Produce NASM obj assembler Anasmob j on the
12. Error Local class definitions are not allowed Classes must be defined globally They cannot be defined inside a procedure or function Fatal Anonymous class definitions are not allowed An invalid object class declaration was en countered i e an object or class without methods that isn t derived from another object or class For example Type o object a longint end 132 APPENDIX C COMPILER MESSAGES will trigger this error Note The object arg1 has no VMT This is a note indicating that the declared object has no virtual method table Error Illegal parameter list You are calling a function with parameters that are of a different type than the declared parameters of the function Error Wrong number of parameters specified for call to arg1 There is an error in the param eter list of the function or procedure the number of parameters is not correct Error overloaded identifier arg1 isn t a function The compiler encountered a symbol with the same name as an overloaded function but it is not a function it can overload Error overloaded functions have the same parameter list You re declaring overloaded functions but with the same parameter list Overloaded function must have at least different parameter in their declaration Error function header doesn t match the previous declaration arg1 You declared a function with the same parameters but different result type or function modifiers
13. 00 eae ere E eR Pade es 35 GLI Staring ihe IDE 2 0 cesos cs be hae a meee aa 35 61 2 IDE command line opens a OS ee E 35 OLS he Wb sete ok oak eed Oh 6 eA BSS Aww Seeds bY 36 62 Navigate mthe IDE 22 6 284608 Fe ERS eae ea De ea ee 37 621 Using the keyboard gt se se a dao ce eR a a ds eS 37 G22 Using tne mouss lt a 6 ee e eS 37 O23 a oe A Re ee ae 38 Do WONS oe AN 38 631 Window asi s bk rr RD REA SARE eee See 38 CONTENTS 6 3 2 Sizing and moving windows e 39 6 3 3 Working with multiple windows 2 6 lt lt lt lt ee 40 634 Diales windows e csc eam ee puspa ae A eee ee 40 Ga TIEM o 22 a A ed A o a e eee Oe amp 40 Al Accessme Ihe MeN 26 2 2646 eae Se A ed 40 64 2 ThE PUSIERA occasion da ss 41 GAS Tie ALICIA E A es PSY Se ee ee a 42 OA The Scar cocinar a e ao ee 43 6043 The RUE coco e See ee we 43 645 The Complement lt s ce eG eh OER a e SE eS 44 64 7 The Debus memi s lt sea ce ew iA Ae he See REE Se 44 OAS The TOIS DEM coa Es eS 45 649 TheOptons Men 2 ka dk se pee ee ee Pa Pe es 45 64 10 The Window memi s co c cb boak espi be we ae eee eos 46 OAIT The Hep Wien lt lt he dee dts ee Sheth eee a es 47 Go IBQUINSTERE ooo a Ae ee bs Pee e eh he 47 Bol Theat mod s ecaro etera daw ee Bee a ew eae cea glee 47 Gi IOS aa dei eb ane adie hee ae ee oon eh eee wah a G 47 033 Setting bookmarks s s se coke spa ea ee ee 48 654 Junpmetonsource We so ced Gee ee Ee eee eee
14. An import name is required Some targets need a name for the imported procedure or a cdec1 specifier Error Division by zero A division by zero was encounted Error Invalid floating point operation An operation on two real type values produced an over flow or a division by zero Error Upper bound of range is less than lower bound The upper bound of an array declaration is less than the lower bound and this is not possible 139 APPENDIX C COMPILER MESSAGES Warning string arg1 is longer than arg2 The size of the constant string is larger than the size you specified in string type definition Error string length is larger than array of char length The size of the constant string is larger than the size you specified in the Array x y of char definition Error Illegal expression after message directive Free Pascal supports only integer or string val ues as message constants Error Message handlers can take only one call by ref parameter A method declared with the message directive as message handler can take only one parameter which must be declared as call by reference Parameters are declared as call by reference using the var directive Error Duplicate message label arg1 A label for a message is used twice in one object class Error Self can only be an explicit parameter in methods which are message handlers The Self parameter can only be passed explicitly to a method which is declared as message handler
15. To resize a window e Using the mouse click on the lower right corner of the window and drag it e Using the keyboard go into the size move mode by pressing CTRL F5 or selecting the menu item WindowlSize Move The window frame will change to green to indicate that the IDE is in size move mode Now hold down the SHIFT key and press one of the cursor keys in order to resize the window Press ENTER to leave the size move mode Pressing ESC will restore the old size Not all windows can be resized This applies for example to dialog windows section 6 3 4 page 40 A window can also be hidden To hide a window the CTRL F6 key combination can be used or the WindowlHide menu may be selected To restore a Hidden window it is necessary to select it from the window list More information about the window list can be found in the next section 39 CHAPTER 6 THE IDE 6 3 3 Working with multiple windows When working with larger projects it is likely that multiple windows will appear on the desktop However only one of these windows will be the active window all other windows will be inactive An inactive window is identified by a grey frame An inactive window can be made active in one of several ways e Using the mouse activate a window by clicking on it Using the keyboard pressing F6 will step through all open windows To activate the previously activated window SHIFT F6 can be used e The menu item Window Next c
16. t select them e Where you want to install the default location is C APP In order to run Free Pascal from any directory on your system you must extend your path variable to contain the C PP BIN directory Usually this is done in the AUTOEXEC BAT file It should look something like this SET PATH PATH C PP 2 2 BIN i386 DOS for DOS or SET PATH PATH S C PP 2 2 BIN i386 0S2 for OS 2 Again assuming that you installed in the default location On OS 2 Free Pascal installs some libraries from the EMX package if they were not yet installed The installer will notify you if they should be installed They are located in the C PP DLL directory The name of this directory should be added to the LIBPATH directive in the config sys file LIBPATH XXX C PP DLL Obviously any existing directories in the LIBPATH directive indicated by XXX in the above exam ple should be preserved 12 CHAPTER 2 INSTALLING THE COMPILER Figure 2 2 Win32 asic system for Win32 required 7345 KB Optional Installation The coprocessor emulation For people who have an older CPU type without math coprocessor i387 it is necessary to install a coprocessor emulation since Free Pascal uses the coprocessor to do all floating point operations The installation of the coprocessor emulation is handled by the installation program INSTALL EXE under DOS and WINDOWS 2 2 3 Installing under Linux Mandatory installat
17. the prefix lib will be prepended under LINUX The extension will be set to a for static libraries for shared libraries the extensions are so on linux and d11 under WINDOWS NT and Os 2 As an example the following command ppumove o both e ppl ppu ppu timer ppu 104 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL will generate the following output under LINUX PPU Mover Version 0 99 7 Copyright c 1998 by the Free Pascal Development Team Processing ppu ppu Done Processing timer ppu Done Linking timer o ppu o Done And it will produce the following files 1 libboth so The shared library containing the code from ppu o and timer o Under WINDOWS NT this file would be called both dll 2 timer ppl The unit file that tells the Free Pascal compiler to look for the timer code in the library 3 ppu ppl The unit file that tells the Free Pascal compiler to look for the ppu code in the library You could then use or distribute the files libboth so timer ppl and ppu ppl 8 8 ptop Pascal source beautifier 8 8 1 ptop program ptop is a source beautifier written by Peter Grogono based on the ancient pretty printer by Ledgard Hueras and Singer modernized by the Free Pascal team objects streams configurability etc This configurability and the thorough bottom up design are the advantages of this program over the diverse Turbo Pascal source beautifiers on e g SIMTEL The program is qui
18. Define the symbol name xxx This can be used to conditionally compile parts of your code D Generate a DEF file for OS 2 Dd Set the description of the executable library WINDOWS Dv Set the version of the executable library WINDOWS E Same as Cn g Generate debugging information for debugging with gdb gc Generate checks for pointers This must be used with the gh command line option When this options is enabled it will verify that all pointer accesses are within the heap gg Same as g gh Use the heaptre unit see Unit reference Produces a report about heap usage after the program exits gl Use the lineinfo unit see Unit reference Produces file name line number information if the program exits due to an error goXXX set debug information options One of the options is dwarfsets It enables dwarf set debug information this does not work with gdb versions prior to 6 5 gp Preserve case in stabs symbol names Default is to uppercase all names gs Write stabs debug information gt Trash local variables This writes a random value to local variables at procedure start This can be used to detect uninitialized variables gv Emit info for valgrind gw Emit dwarf debugging info version 2 gw2 Emit dwarf debugging info version 2 gw3 Emit dwarf debugging info version 3 kxxx Pass xxx to the linker Oxxx Optimize the compiler s output xxx can have one of the following values aPARA
19. Error Control flow statements aren t allowed in a finally block It isn t allowed to use the con trol flow statements break continue and exit inside a finally statement The following example shows the problem 155 APPENDIX C COMPILER MESSAGES try Pr finally exit This exit ISN T allowed end If the procedure p raises an exception the finally block is executed If the execution reaches the exit it s unclear what to do exit the procedure or search for another exception handler Warning Parameters size exceeds limit for certain cpu s This indicates that you are declaring more than 64K of parameters which might not be supported on other processor targets Warning Local variable size exceed limit for certain cpu s This indicates that you are declaring more than 32K of local variables which might not be supported on other processor targets Error Local variables size exceeds supported limit This indicates that you are declaring more than 32K of local variables which is not supported by this processor Error BREAK not allowed You re trying to use break outside a loop construction Error CONTINUE not allowed You re trying to use continue outside a loop construction Fatal Unknown compilerproc arg1 Check if you use the correct run time library The com piler expects that the runtime library contains certain subroutines If you see this error and you didn t change the runtime library code it s very l
20. Extend selection one page down Extend selection to the beginning of the file Extend selection to the end of the file SHIFT ARROW LEFT SHIFT ARROW RIGHT SHIFT POS1 SHIFT END SHIFT ARROW UP SHIFT ARROW DOWN SHIFT END CTRL SHIFT ARROW LEFT CTRL SHIFT ARROW RIGHT SHIFT PAGEUP SHIFT PAGEDOWN CTRL SHIFT POS1 CTRL SHIFT PAGEUP CTRL SHIFT END CTRL SHIFT PAGEUP Table 6 10 Misc commands Command Shortcut key Alternative Save file F2 CTRL K S Open file F3 Search CTRL Q F Search again CTRL L Search and replace CTRL Q A Set mark Goto mark Undo CTRL K N where n can be 0 9 CTRL Q N where n can be 0 9 ALT BACKSPACE 88 Chapter 7 Porting and portable code 7 1 Free Pascal compiler modes The Free Pascal team tries to create a compiler that can compile as much as possible code produced for Turbo Pascal Delphi or the Mac pascal compilers this should make sure that porting code that was written for one of these compilers is as easy as possible At the same time the Free Pascal developers have introduced a lot of extensions in the Object Pascal language To reconcile these different goals and to make sure that people can produce code which can still be compiled by the Turbo Pascal and Delphicompilers the compiler has a concepts of com piler modes In a certain compiler mode the compiler has certain functionalities switched on or off This allows to introduce a compatibility mode in wh
21. For WINDOWS there is a WINDOWS installer setup exe This is a normal installation program which offers the usual options of selecting a directory and which parts of the distribution you want to install It will optionally associate the pp or pas extensions with the text mode IDE It is not recommended to install the compiler in a directory which has spaces in it s path name Some of the external tools do not support filenames with spaces in them and you will have problems creating programs 2 2 2 Installing under DOS or OS 2 Mandatory installation steps First you must get the latest distribution files of Free Pascal They come as zip files which you must unzip first or you can download the compiler as a series of separate files This is especially useful if you have a slow connection but it is also nice if you want to install only some parts of the compiler distribution The distribution zip files for DOS or OS 2 contain an installation program INSTALL EXE You must run this program to install the compiler The screen of the DOS or OS 2 installation program looks like figure 2 1 The program allows you to select CHAPTER 2 INSTALLING THE COMPILER Figure 2 1 The DOS install program screen i General e What components you wish to install e g do you want the sources or not do you want docs or not Items that you didn t download when downloading as separate files will not be enabled i e you can
22. For compatibility fpc cfg will be searched first and if not found the file ppc386 cfg will be searched and used 3 1 6 About long filenames Free Pascal can handle long filenames on all platforms except DOS On Windows it will use support for long filenames if it is available which is not always the case on older versions of Windows If no support for long filenames is present it will truncate unit names to 8 characters It is not recommended to put units in directories that contain spaces in their names since the external GNU linker doesn t understand such filenames 3 2 Compiling a program Compiling a program is very simple Assuming that you have a program source in the file prog pp you can compile this with the following command fpc options prog pp The square brackets indicate that what is between them is optional If your program file has the pp or pas extension you can omit this on the command line e g in the previous example you could have typed fpc options prog If all went well the compiler will produce an executable file You can execute it straight away you don t need to do anything else You will notice that there is also another file in your directory with extension O This contains the object file for your program If you compiled a program you can delete the object file 0 but don t delete it if you compiled a unit This is because the unit object file contains the code of the uni
23. Overridden methods must have a related return type This code may crash it depends on a Delphi parser bu If you declare overridden methods in a class definition they must have the same return type Some versions of Delphi allow you to change the return type of interface methods and even to change procedures into functions but the resulting code may crash depending on the types used and the way the methods are called Error Dispatch IDs must be ordinal constants The dispid keyword must be followed by an ordinal constant the dispid index Error The range of the array is too large Regardless of the size taken up by its elements an array cannot have more than high ptrint elements Additionally the range type must be a subrange of ptrint Error The address cannot be taken of bit packed array elements and record fields If you declare an array or record as packed in Mac Pascal mode or as packed in any mode with bitpacking on it will be packed at the bit level This means it becomes impossible to take addresses of individual array elements or record fields The only exception to this rule is in the case of packed arrays elements whose packed size is a multple of 8 bits Error Dynamic arrays cannot be packed Only regular and possibly in the future also open ar rays can be packed Error Bit packed array elements and record fields cannot be used as loop variables If you de clare an array or record as packed in Mac Pascal mode or as
24. Return compiler date iV Return short compiler version iW Return full compiler version iso Return compiler OS TISE Return compiler host processor iTo Return target OS iTP Return target processor I lt x gt Add lt x gt to include path k lt x gt Pass lt x gt to the linker 1 Write logo M lt x gt Set language mode to lt x gt Mfpc Free Pascal dialect default 122 APPENDIX A ALPHABETICAL LISTING OF COMMAND LINE OPTIONS Mo bjfpc FPC mode with Object Pascal support Mdelphi Delphi 7 compatibility mode Mtp TP BP 7 0 compatibility mode Mmacpas acintosh Pascal dialects compatibility mode Sf Do not read the default config files N lt x gt Node tree optimizations Nu Unroll loops 0 lt x gt Change the name of the executable produced to lt x gt 0 lt x gt Optimizations O Disable optimizations 01 Level 1 optimizations quick and debugger friendly 02 Level 2 optimizations Ol quick optimizations 03 Level 3 optimizations 02 slow optimizations Oa lt x gt lt y gt Set alignment 0o NO lt x gt Enable or disable optimizations see fpc i for possible values Op lt x gt Set target cpu for optimizing see fpc i for possible values 0s Optimize for size rather than speed pg Generate profile code for gprof defines FPC_PROFILE R lt x gt Assembler reading style Rdefault Use default assembler for target S lt x gt Syntax options 52 Same as Mobj
25. Text to the screen This can be useful to display warnings if certain options are set Example FIFDEF DEBUG WRITE Setting debugging ON 79g ENDIF If DEBUG is defined this will produce a line Setting debugging ON and will then switch on debugging information in the compiler 5 2 8 INCLUDE Syntax INCLUDE filename INCLUDE instructs the compiler to read the contents of filename before continuing to process options in the current file This can be useful if you want to have a particular configuration file for a project or under LINUX in your home directory but still want to have the global options that are set in a global configuration file Example 33 CHAPTER 5 COMPILER CONFIGURATION IFDEF LINUX INCLUDE etc fpc cfg ELSE IFDEF GO32V2 INCLUDE c pp bin fpc cfg ENDIF ENDIF This will include etc fpc cfg if you re on a LINUX machine and will include c pp bin fpc cfg on a DOS machine 5 2 9 SECTION Syntax SECTION name The SECTION directive acts as a IFDEF directive only it doesn t require an ENDIF directive The special name COMMON always exists i e lines following SECTION COMMON are always read 5 3 Variable substitution in paths To avoid having to edit your configuration files too often the compiler allows you to specify the following variables in the paths that you f
26. a batch file that will contain the external linking and archiving commands that must be executed The name of this batch file is pmove sh on LINUX and Unix like OSes and pmove bat on WINDOWS and Dos d xxx Set the directory in which to place the output files to XXX e xxx Set the extension of the moved unit files to xxx By default this is ppl You don t have to specify the dot 0 xxx Set the name of the output file i e the name of the file containing all the units This parameter is mandatory when you use multiple files On LINUX ppumove will prepend this name with lib if it isn t already there and will add an extension appropriate to the type of library q Operate silently s Make a static library instead of a dynamic one By default a dynamic library is made on LINUX w Tell ppumove that it is working under WINDOWS NT This will change the names of the linker and archiving program to ldw and arw respectively h or Display a short help The action of the ppumove program is as follows It takes each of the unit files and modifies it so that the compiler will know that it should look for the unit code in the library The new unit files will have an extension ppu this can be changed with the e option It will then put together all the object files of the units into one library static or dynamic depending on the presence of the s option The name of this library must be set with the o option If needed
27. a file with the same name but an extension of ans If this file is found this will be interpreted as a file with ANSI escape sequences and these will be used to display a text image The displays of the IDE dialogs in the IDE help files are made in this way The menu item HelplFiles permits help files to be added to and deleted from the list of files in the help table of contents The help files dialog is displayed in figure 6 37 Figure 6 37 The help files dialog Frequently Asked Questions GIN The dialog lists the files that will be presented in the table of contents window of the help system Each entry has a small descriptive title and a filename next to it The following actions are available when adding help files New Adds a new file IDE will display a prompt in which the location of the help file should be entered If the added file is an HTML file a dialog box will be displayed which asks for a title This title will then be included in the contents of help Delete Deletes the currently highlighted file from the help system It is not deleted from the hard disk only the help system entry is removed Cancel Discards all changes and closes the dialog OK Saves the changes and closes the dialog The Free Pascal documentation in HTML format can be added to the IDE s help system This way the documentation can be viewed from within the IDE If Free Pascal has been installed using the installer the installer
28. a unit which was compiled with a different FPU mode Trying to compile code while using units which were not compiled with the same floating point format mode Either all code should be compiled with FPU emulation on or with FPU emulation off Loading interface units from argl When you use the vu flag the compiler warns that it is start ing to load the units defined in the interface part of the unit Loading implementation units from argl When you use the vu flag the compiler warns that it is starting to load the units defined in the implementation part of the unit Interface CRC changed for unit argl When you use the vu flag the compiler warns that the CRC calculated for the interface has been changed after the implementation has been parsed Implementation CRC changed for unit arg1 When you use the vu flag the compiler warns that the CRC calculated has been changed after the implementation has been parsed Finished compiling unit argl When you use the vu flag the compiler warns that it has finished compiling the unit Add dependency of arg1 to arg2 When you use the vu flag the compiler warns that it has added a dependency between the two units 160 APPENDIX C COMPILER MESSAGES No reload is caller arg1 When you use the vu flag the compiler warns that it will not reload the unit because it is the unit that wants to load this unit No reload already in second compile arg1 When you use the vu flag the compiler
29. allowed Invalid Reference Cannot use _ SELF outside a method Cannot use _ OLDEBP outside a nested procedure Invalid segment override expression Strings not allowed as constants Switching sections is not allowed in an assembler block Invalid global definition Line separator expected Invalid local common definition Invalid global common definition assembler code not returned to text invalid opcode size Invalid character lt Invalid character gt Unsupported opcode Invalid suffix for intel assembler Extended not supported in this mode Comp not supported in this mode Invalid Operand Override operator not supported C 11 3 m68k specific errors Increment and Decrement mode not allowed together You are trying to use dec inc mode together Invalid Register list in movem fmovem The register list is invalid Normally a range of registers should be separated by and individual registers should be separated by a slash Invalid Register list for opcode 68020 mode required to assemble 167 Appendix D Run time errors Applications generated by Free Pascal might generate run time errors when certain abnormal con ditions are detected in the application This appendix lists the possible run time errors and gives information on why they might be produced 1 Invalid function number An invalid operating system call was attempted 2 File not found Reported when trying to erase rename or open a non existent file 3 P
30. any are argl You are trying to overload an operator which cannot be overloaded The following operators can be overloaded y xy i y gt lt lt gt is as in KK Error Comparative operator must return a boolean value When overloading the operator the function must return a boolean value Error Only virtual methods can be abstract You are declaring a method as abstract when it is not declared to be virtual Fatal Use of unsupported feature You re trying to force the compiler into doing something it cannot do yet Error The mix of different kind of objects class object interface etc isn t allowed You can not derive objects classes cppclasses and interfaces intertwined E g a class cannot have an object as parent and vice versa Warning Unknown procedure directive had to be ignored arg1 The procedure directive you specified is unknown Error absolute can only be associated to one variable You cannot specify more than one vari able before the absolute directive Thus the following construct will provide this error Var Z Longint X Y Longint absolute Z Error absolute can only be associated with a var or const The address of an absolute direc tive can only point to a variable or constant Therefore the following code will produce this error Procedure X var p longint absolute x Error Only one variable can be initialized You cannot specify more than one variable with a i
31. be opened with the DebuglWatches menu The watch list window is shown in figure 6 14 Pressing ENTER or the space bar will show the watch property dialog for the currently highlighted watch in the watches window The list of watches is updated whenever the IDE resumes control when debugging a program 57 CHAPTER 6 THE IDE Figure 6 13 The watch property dialog E Current value Previous value Figure 6 14 The watch list window EOE Hatches a Unknown value gt 6 9 3 The call stack The call stack helps in showing the program flow It shows the list of procedures that are being called at this moment in reverse order The call stack window can be shown using the DebuglCall Stack menu It will show the address or procedure name of all currently active procedures with their filename and addresses If parameters were passed they will be shown as well The call stack is shown in figure 6 15 By pressing the space bar in the call stack window the line corresponding to the call will be high lighted in the edit window 6 9 4 The GDB window The GDB window provides direct interaction with the GDB debugger In it GDB commands can be typed as they would be typed in GDB The response of GDB will be shown in the window Some more information on using GDB can be found in section 10 2 page 116 but the final reference is of course the GDB manual itself gt The GDB window is shown in figure 6 16 3 A
32. cased versions of the same filename are in the path RTTI is NOT stored in the same way as for Delphi The format is mostly compatible but may differ This should not be a problem if the API of the TypeInfo unit is used and no direct access to the RTTI information is attempted By default sets are of different size than in Delphi but set size can be specified using directives or command line switches 96 CHAPTER 7 PORTING AND PORTABLE CODE Likewise by default enumeration types are of different size than in Delphi Here again the size can be specified using directives or command line switches In general one should not make assumptions about the internal structure of complex types such as records objects classes and their associated structure For example the VMT table layout is different the alignment of fields in a record may be different etc e The same is true for basic types on other processors the high and low bytes of a word or integer may not be at the same location as on an Intel processor the endianness is different Names of local variables and method arguments are not allowed to match the name of a prop erty or field of the class this is bad practise as there can be confusion as to which of the two 1s meant 7 3 3 Delphi compatibility mode Switching on Dephi compatibility mode has the following effect 1 Support for Classes exceptions and threadvars is enabled 2 The objpas is loaded as the first
33. cio varios aE a a A Sow ao ee 77 6 12 Customizing the IDE ocean ee ee See eR we 77 6 12 Perren ove 6 o Bae es EMER eG a Eee se es 78 612 2 Thedesktop ooo Sea be ew eA ee ee eee Ee 79 0127 TOSB IOS opacar EA es eS 80 6 124 Keyboard amp Mouse ono conser dad Se eS 82 6 13 The help system oia a a a br es 83 6 13 1 Navigating m the help system ee ocni em sas ra ERD Ee amp 83 6 13 2 Working with help files 06064 5 44604 eb ts Dee eee bees 83 6 13 3 The aboutdiglop coros ona a EE REA ea he 84 6 1 Keyboard Shortcuts n pece aeaea perp EAR eR Ha ES eS 85 7 Porting and portable code 89 71 Free Paseal compiler modes lt o specc he eR ERR ES ee PR E e 89 Te TS Pa ios ke a e eho eh o eS 90 Vol Things that llaga fe des ee Se OSS Re Be Ee Se es 90 Taa Things which We BAD eo ce ah ee ee BP ewe ee E 91 7 2 3 Turbo Pascal compatibility mode 6 ee see ee ee ee 93 724 Anoteon long file names under DOS 45 55485 bed oes 95 za Peeing Delphi code o coso eh me e Be ee amp 95 7 3 1 Missing language constructs gt oe ce coe a rss e a a E a 95 7 3 2 Missing calls API incompatibilities oaaae 96 7 3 3 Delphicompatibility mode os riera a e 97 7 3 4 Best practices forporting lt lt dns ss ados eS 97 74 Wine portable code os sama E e e 97 8 Utilities that come with Free Pascal 100 1 Bento programs and examples cc ee ss RR A N Y 100 Sa PENARE cio e Ra ears E Bs eG eke ae 100 8 3 Tpdoc Pascal Umit documenter
34. command line Use MASM Produce MASM Microsoft assembler assembler Amasm on the command line Use TASM Produce TASM Turbo Assembler assembler At asm on the command line Use coff Write binary coff files directly using the internal assembler g032v2 Acof f on the command line Use pecoff Write binary pecoff files files directly using the internal writer Win32 6 11 5 Linker options The linker options can be set in the menu OptionslLinker It permits the specification of how libraries and units are linked and how the linker should be called The linker options dialog is shown in figure 6 29 The following options can be set Call linker after If this option is set then a script is written which calls the linker This corresponds to the s option on the command line s see page 5 1 4 74 CHAPTER 6 THE IDE Figure 6 28 The assembler options tab S ntax Code eneration rocessor erbose rouser Assembler reader ij Use default output Assembler info G Conditio al defines Additional ompiler args Figure 6 29 The linker options dialog I Linking stage GDh MAEA OEE D Only link to static library Only use static libraries Preferred library type With this option the type of library to be linked in can be set Target default This depends on the platform Dynamic libraries Tries to link in units in dynamic libraries option XD on the command line
35. defined by Turbo Pascal are supported This is even more so if you use the So or S2 switches In the following sections we will list the Turbo Pascal and Delphi constructs which are not supported in Free Pascal and we will list in what ways Free Pascal extends Turbo Pascal 7 2 1 Things that will not work Here we give a list of things which are defined allowed in Turbo Pascal but which are not supported by Free Pascal Where possible we indicate the reason 1 Duplicate case labels are permitted in Turbo Pascal but not in Free Pascal This is actually a bug in Turbo Pascal and so support for it will not be implemented in Free Pascal 2 In Turbo Pascal parameter lists of previously defined functions and procedures did not have to match exactly In Free Pascal they must The reason for this is the function overloading mechanism of Free Pascal However the M see page 5 1 5 option overcomes this restriction 3 The Turbo Pascal variables MEM MEMW MEML and PORT for memory and port access are not available in the system unit This is due to the operating system Under DOS the extender unit GO32 PPU implements the mem constuct Under LINUX the ports unit implements such a construct for the Ports variable 4 Turbo Pascal allows you to create procedure and variable names using words that are not permitted in that role in Free Pascal This is because there are certain words that are reserved in Free Pascal and Delphi
36. depends on the platform for which the IDE was compiled Dos g032v1 This switch will dissapear in time as this target is no longer being maintained Dos go32v2 Compile for DOS using version 2 of the Go32 extender FreeBSD Compile for FREEBSD Linux Compile for LINUX 68 CHAPTER 6 THE IDE Figure 6 22 The compilation target dialog K OS 2 Compile for OS 2 using the EMX extender Windows Compile for WINDOWS The currently selected target operating system is shown in the Target menu item in the Compile menu Initially this will be set to the operating system for which the IDE was compiled 6 11 4 Compiler options The menu OptionslCompiler allow the settting of options that affect the compilers behaviour When this menu item is chosen a dialog pops up that displays several tabs There are six tabs Syntax Here options can be set that affect the various syntax aspects of the code They correspond mostly to the S option on the command line section 5 1 5 page 29 Code generation These options control the generated code they are mostly concerned with the C and X command line options Verbose These set the verbosity of the compiler when compiling The messages of the compiler are shown in the compiler messages window can be called with F12 Browser Options concerning the generated browser information Browser information needs to be generated for the symbol browser to work Assembler Options co
37. etc to the file named Xxx FExxx Write the executable and units to directory Xxx instead of the current directory If this option is followed by a o option o see page 5 1 4 and this option contains a path component then the o path will override the FE setting Ffxxx Add xxx to the framework path only for Darwin Fixxx Add Xxx to the include file search path 24 CHAPTER 5 COMPILER CONFIGURATION Flxxx Add xxx to the library search path This is also passed to the linker FLxxx LINUX only Use XXX as the dynamic linker The default is lib ld linux so 2 or lib ld linux so 1 depending on which one is found first Fmxxx Load the unicode conversion table from file x txt in the directory where the compiler is located Only used when Fc is also in effect Foxxx Add xxx to the object file search path This path is used when looking for files that need to be linked in Frxxx Specify xxx as the file which contain the compiler messages This will override the com piler s built in default messages which are in english FRxxx set the resource res linker to XXX Fuxxx Add xxx to the unit search path Units are first searched in the current directory If they are not found there then the compiler searches them in the unit path You must always supply the path to the system unit The xxx path can contain a single wildcard which will be expanded to all possible directory names found at that locat
38. file 156 APPENDIX C COMPILER MESSAGES Error Can t create object file argl The mentioned file can t be created Check if you have got access permissions to create this file Error Can t create archive file arg1 The mentioned file can t be created Check if you have ac cess permissions to create this file Error Assembler arg1 not found switching to external assembling The assembler program was not found The compiler will produce a script that can be used to assemble and link the pro gram Using assembler arg An informational message saying which assembler is being used Error Error while assembling exitcode arg1 There was an error while assembling the file using an external assembler Consult the documentation of the assembler tool to find out more infor mation on this error Error Can t call the assembler error arg1 switching to external assembling An error occurred when calling an external assembler The compiler will produce a script that can be used to assemble and link the program Info Assembling arg An informational message stating which file is being assembled Info Assembling with smartlinking argl An informational message stating which file is being assembled using smartlinking Warning Object arg1 not found Linking may fail One of the object files is missing and link ing will probably fail Check your paths Warning Library arg1 not found Linking may fail One of the library files is
39. file o directive the compiler will look for this file in the same way as it looks for include files 1 It will look in the path specified in the object file name 2 It will look in the directory where the current source file is 3 It will look in all directories specified in the object file search path You can add files to the object file search path with the Fo see page 5 1 3 option 19 CHAPTER 3 COMPILER USAGE 3 1 5 Configuration file Not all options must be given on the compiler command line The compiler can use a configuration file which can contain the same options as on the command line Unless you specify the n see page 5 1 1 option the compiler will look for a configuration file fpc cfg in the following places e Under UNIX such as LINUX 1 The current directory 2 Your home directory it looks for fpc cfg 3 The directory specified in the environment variable PPC_CONFIG_PATH and if it is not set it will look in the etc directory above the compiler directory For instance if the compiler is in usr local bin it will look in usr local etc 4 The directory etc e Under all other OSes 1 The current directory 2 If it is set the directory specified in the environment variable PPC_CONFIG_PATH 3 The directory where the compiler is Versions prior to version 1 0 6 of the compiler used a configuration file ppc386 cfg This file is still searched but its usage is considered deprecated
40. future when the meaning of the switch may change Note Switching assembler to default source writing assembler This notifies you that the assem bler has been changed because you used the a switch which can t be used with a binary assembler writer Warning Assembler output selected arg1 is not compatible with arg2 Warning arg1 assembler use forced The assembler output selected can not generate object files with the correct format Therefore the default assembler for this target is used instead Reading options from file arg1 Options are also read from this file Reading options from environment arg1 Options are also read from this environment string Handling option arg1 Debug info that an option is found and will be handled press enter Message shown when help is shown page per page When pressing the ENTER Key the next page of help is shown If you press q and then ENTER the compiler exits Hint Start of reading config file argl Start of configuration file parsing 162 APPENDIX C COMPILER MESSAGES Hint End of reading config file arg1 End of configuration file parsing interpreting option arg1 The compiler is interpreting an option interpreting firstpass option arg1 The compiler is interpreting an option for the first time interpreting file option arg1 The compiler is interpreting an option which it read from the con figuration file Reading config file arg1 The compiler is starting t
41. list of reserved words absolute abstract and array as asm assembler begin break case cdecl class const constructor continue cppclass deprecated destructor div do downto else end except exit export exports external experimental fail false far file finally for forward function goto if implementation in index inherited initialization inline interface interrupt is label library mod name near nil not object of on operator or otherwise packed 125 popstack private procedure program property protected public raise record reintroduce repeat self set shl shr stdcall string then to true try type unimplemented unit until uses var virtual while with xor Appendix C Compiler messages This appendix is meant to list all the compiler messages The list of messages is generated from he compiler source itself and should be fairly complete At this point only assembler errors are not in the list C 1 General compiler messages This section gives the compiler messages which are not fatal but which display useful information The number of such messages can be controlled with the various verbosity level v switches Compiler arg1 When the vt switch is used this line tells you what compiler is used Compiler OS argl When the vd switch is used this line tells you what the source operating system is Info Target OS argl Whe
42. most C constructs that one finds in a C header file and attempts to translate them to their Pascal counterparts See below constructs for a full description of what the translator can handle The unit with Pascal declarations can then be used to access code written in C The output of the h2pas program is written to a file with the same name as the C header file that was used as input but with the extension pp The output file that h2pas creates can be customized in a number of ways by means of many options 8 4 1 Options The output of h2pas can be controlled with the following options d Use external for all procedure and function declarations D Use external libname name func_name for function and procedure declarations e Emit a series of constants instead of an enumeration type for the C enum construct i Create an include file instead of a unit omits the unit header 1 libname specify the library name for external function declarations o outfile Specify the output file name Default is the input file name with the extension replaced by Pp p Use the letter P in front of pointer type parameters instead of s Strip comments from the input file By default comments are converted to comments but they may be displaced since a comment is handled by the scanner t Prepend typedef type names with the letter T used to follow Borland s convention that all types should be defined with T v Replace pointer
43. occurs show all procedures Corresponds to vb on the command line The browser tab of the compiler options dialog is shown in figure 6 27 In this dialog the browser options can be set No browser default No browser information is generated by the compiler Only global browser Browser information is generated for global symbols only i e symbols de fined not in a procedure or function b on the command line Local and global browser Browser information is generated for all symbols i e also for symbols that are defined in procedures or functions b1 on the command line 72 CHAPTER 6 THE IDE Figure 6 26 The verbosity options tab Compiler Suitches Verbose Verbose Switches MI Warnings Remark If no browser information is generated the symbol browser of the IDE will not work The assembler tab of the compiler options dialog is shown in figure 6 28 The actual dialog may vary as it depends on the target CPU the IDE was compiled for In this dialog the assembler reader and writer options can be set Assembler reader This permits setting the style of the assembler blocks in the sources AT amp T assembler The assembler is written in AT amp T style assembler Rat t on the command line Intel style assembler The assembler is written in Intel style assembler blocks Rintel on the command line remark that this option is global but locally the assembler style can be changed with compiler directives
44. overload the previously declared x begin Lise end This construction will generate a compiler error because the compiler didn t find a definition of procedure x v longint Instead you should define your procedure x as procedure x v longint This correctly defines the previously declared x begin Le end The command line option So see page 5 1 5 disables overloading When you use it the above will compile as in Turbo Pascal Operator overloading Free Pascal allows operator overloading e g you can define the operator for matrices On FAT 16 and FAT32 systems long file names are supported 7 2 3 Turbo Pascal compatibility mode When you compile a program with the Mtp switch the compiler will attempt to mimic the Turbo Pascal compiler in the following ways Assigning a procedural variable doesn t require an operator One of the differences between Turbo Pascal and Free Pascal is that the latter requires you to specify an address operator when assigning a value to a procedural variable In Turbo Pascal compatibility mode this is not required Procedure overloading is disabled If procedure overloading is disabled the function header doesn t need to repeat the function header Forward defined procedures don t need the full parameter list when they are defined Due to the procedure overloading feature of Free Pascal you must always specify the parameter list of a function whe
45. parameters with call by reference parameters Use with care because some calls can expect a Nil pointer w Header file is a win32 header file adds support for some special macros x Handle SYS_TRAP of the PalmOS header files 8 4 2 Constructs The following C declarations and statements are recognized defines Defines are changed into Pascal constants if they are simple defines Macros are changed wherever possible to functions however the arguments are all integers so these must be changed manually Simple expressions in define staments are recognized as are most arith metic operators addition substraction multiplication division logical operators comparison operators shift operators The C construct A B C is also recognized and translated to a Pascal construct with an IF statement This is buggy however 101 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL preprocessor statements The conditional preprocessing commands are recognized and translated into equivalent Pascal compiler directives The special ifdef _ cplusplus is also recognized and removed typedef A typedef statement is changed into a Pascal type statement The following basic types are recognized e char changed to char e float changed to real double in Free Pascal e int changed to longint e long changed to longint e long int changed to longint e n hort changed to integer nsigned changed to cardinal nsigned cha
46. pressed 2 The action of mouse buttons may be reversed i e the actions of the left mouse button can be assigned to the right mouse button and vice versa Throughout the manual it is assumed that the actions of the mouse buttons are not reversed 3 The mouse is not always available even if a mouse is installed e The IDE is running under LINUX through a telnet connection from a WINDOWS machine e The IDE is running under LINUX in an X term under X windows In this case it depends on the terminal program under Konsole the KDE terminal 1t works 2See section 6 12 4 page 82 for more information on how to reverse the actions of the mouse buttons 37 CHAPTER 6 THE IDE 4 On Windows the console has an option Quick edit allowing text to be copied to the clipboard by selecting text in the console window If this mode is enabled the mouse will not work The Quick edit option should be disabled in the console window s properties in order for the IDE to receive mouse events 6 2 3 Navigating in dialogs Dialogs usually have a lot of elements in them such as buttons edit fields memo fields list boxes and so on To activate one of these fields choose one of the following methods 1 Click on the element with the mouse 2 Press the TAB key till the focus reaches the element 3 Press the highlighted letter in the element s label If the focus is currently on an element that allows editing then ALT should b
47. records structs Structs are changed to Pascal records with C packing 102 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL 8 5 h2paspp preprocessor for h2pas h2paspp can be used as a simple preprocessor for h2pas It removes some of the constructs that h2pas has difficulties with h2paspp reads one or more C header files and preprocesses them writing the result to files with the same name as the originals as it goes along It does not accept all preprocesser tokens of C but takes care of the following preprocessor directives define symbol Defines the new symbol symbol Note that macros are not supported if symbol The text following this directive is included if symbol is defined ifdef symbol The text following this directive is included if symbol is defined ifndef symbol The text following this directive is included if symbol is not defined include filename Include directives are removed unless the I option was given in which case the include file is included and written to the output file undef symbol The symbol symbol is undefined 8 5 1 Usage h2paspp accepts one or more filenames and preprocesses them It will read the input and write the output to a file with the same name unless the o option is given in which case the file is written to the specified file Note that only one output filename can be given 8 5 2 Options h2paspp has a small number of options to control its behaviour dsymbol Define th
48. return True or False Error Ordinal expression expected The expression must be of ordinal type i e maximum a Longint This happens for instance when you specify a second argument to Inc or Dec that doesn t evaluate to an ordinal value Error pointer type expected but got arg1 The variable or expression isn t of the type pointer This happens when you pass a variable that isn t a pointer to New or Dispose Error class type expected but got arg1 The variable or expression isn t of the type class This happens typically when 1 The parent class in a class declaration isn t a class 2 An exception handler On contains a type identifier that isn t a class Error Can t evaluate constant expression This error can occur when the bounds of an array you declared do not evaluate to ordinal constants Error Set elements are not compatible You are trying to perform an operation on two sets when the set element types are not the same The base type of a set must be the same when taking the union Error Operation not implemented for sets several binary operations are not defined for sets These include div mod gt and lt The last two may be defined for sets in the future Warning Automatic type conversion from floating type to COMP which is an integer type An implicit type conversion from a real type to a comp is encountered Since comp is a 64 bit integer type this may indicate an error Hint use DIV ins
49. sa enoa Ea e ewe OR ee DEE Ys 117 10 4 Support for gprot the GNU profiler 2 e eeo 2 ee ee ee ee E 118 10 5 Detecting heap memory leaks s o 0 060004 6 See ee eee ee e 118 10 6 Line numbers in run time error backtraces o o 119 10 7 Combining heaptrc and lineinfo o o oo ee 119 A Alphabetical listing of command line options 121 B Alphabetical list of reserved words 125 C Compiler messages 126 C 1 General compiler messages coo e eos sa ee 126 C2 SrconnerinessigES Lin be See ee a a Pe Re eR Pe eS es 127 C3 Parser Messages cocoa ee a ee See ee we aes 132 CA pe checkin CES oos a a RG ee ja de 146 Co Symbol anding od ee Se ee eS oo hoe ewes e A 151 CE Code penerator messages o 2c ee A ea ee 154 CONTENTS C 7 Errors of assembling linking stage lt ec ee 156 C S Executable information messages o ce se e a ESE ee we 158 C29 Unit loadino Messages ona e Soe A A e 158 C10 Command line handlmgemors 2 occiso e A oe 161 CAI Assembler reader emors os x oe Goan are ee Be AR E 163 11 1 General assembler enrors oo e ooe ec 5 ae onerosa 163 CALZ ISSO APOCO sv ok ck oe Os ds a 166 C113 MOS specllc CGE co Ok a Re Ge Be ee 167 D Run time errors 168 E A sample gdb ini file 172 F Options and settings 173 Chapter 1 Introduction 1 1 About this document This is the user s guide for Free Pascal It describes the installation and use of the Free Pascal compiler on the differe
50. should have added the FPC documentation to the list of help files if the documentation was installed as well 6 13 3 The about dialog The about dialog reachable through Help About shows some information about the IDE such as the version number the date it was built what compiler and debugger it uses When reporting bugs about the IDE please use the information given by this dialog to identify the version of the IDE that was used It also displays some copyright information 84 CHAPTER 6 THE IDE 6 14 Keyboard shortcuts A lot of keyboard shortcuts used by the IDE are compatible with WordStar and should be well known to Turbo Pascal users Below are the following tables 1 NY Dn a A In table 6 4 some shortcuts for handling the IDE windows and Help are listed In table 6 6 the navigation keys are described In table 6 7 the editing keys are listed sented In table 6 5 the shortcuts for compiling running and debugging a program are presented In table 6 8 all block command shortcuts are listed In table 6 9 all selection changing shortcuts are presented In table 6 10 some general shortcuts which do not fit in the previous categories are pre Table 6 4 General Command Shortcut key Alternative Help Fl Goto last help topic ALT F1 Search word at cursor position in CTRL Fl help Help index SHIFT F 1 Close active window ALT F3 Zoom Unzoom window F5 Move Zoom ac
51. that are not reserved in Turbo Pascal such as PROTECTED PUBLIC PUBLISHED TRY FINALLY EXCEPT RAISE Using the Mtp switch will solve this problem if you want to compile Turbo Pascal code that uses these words chapter B page 125 for a list of all reserved words 90 CHAPTER 7 PORTING AND PORTABLE CODE 5 The Turbo Pascal reserved words FAR NEAR are ignored This is because their purpose was limited to a 16 bit environment and Free Pascal is a 32 bit 64 bit compiler 6 The Turbo Pascal INTERRUPT directive will work only on the Free Pascal DOS target Other operating systems do not allow handling of interrupts by user programs 7 By default the Free Pascal compiler uses AT amp T assembler syntax This is mainly because Free Pascal uses GNU as However other assembler forms are available For more information see the Programmers guide 8 Turbo Pascal s Turbo Vision is available in Free Pascal under the name of Free Vision which should be almost 100 compatible with Turbo Vision 9 Turbo Pascal s overlay unit is not available It also isn t necessary since Free Pascal is a 32 64 bit compiler so program size shouldn t be an issue 10 The command line parameters of the compiler are different 11 Compiler switches and directives are mostly the same but some extra exist 12 Units are not binary compatible That means that you cannot use a tpu unit file produced by Turb
52. this file is generated by the installation program You may have to check that it is in the correct place see section 5 2 for more information on this 3 1 File searching Before you start compiling a program or a series of units it is important to know where the compiler looks for its source files and other files In this section we discuss this and we indicate how to influence this The use of slashes and backslashes 1 as directory separators is irrelevant the compiler will convert to whatever character is used on the current operating system Examples will be given using slashes since this avoids problems on UNIX systems such as LINUX 3 1 1 Command line files The file that you specify on the command line such as in fpc foo pp will be looked for ONLY in the current directory If you specify a directory in the filename then the compiler will look in that directory fpc subdir foo pp will look for foo pp in the subdirectory subdir of the current directory Under case sensitive file systems such as LINUX and UNIX the name of this file is case sensitive under other operating systems such as DOS WINDOWS NT OS 2 this is not the case 3 1 2 Unit files When you compile a unit or program that needs other units the compiler will look for compiled versions of these units in the following way 16 CHAPTER 3 COMPILER USAGE 1 It will look in the current directory 2 It will look in the directory where th
53. unit This unit redefines some basic types Integer is 32 bit for instance 3 The address operator is no longer needed to set event handlers i e assign to procedural variables or properties 4 Names of local variables and method parameters in classes can match the name of properties or field of the class 5 The String keyword implies AnsiString by default 6 Operator overloading is switched off 7 3 4 Best practices for porting When encountering differences in Delphi FPC calls the best thing to do is not to insert IFDEF statements whenever a difference is encountered but to create a separate unit which is only used when compiling with FPC The missing incompatible calls can then be implemented in that unit This will keep the code more readable and easier to maintain If a language construct difference is found then the Free Pascal team should be contacted and a bug should be reported 7 4 Writing portable code Free Pascal is designed to be cross platform This means that the basic RTL units are usable on all platforms and the compiler behaves the same on all platforms as far as possible The Object Pascal language is the same on all platforms Nevertheless FPC comes with a lot of units that are not portable but provide access to all possibilities that a platform provides The following are some guidelines to consider when writing portable code e Avoid system specific units The system unit the objects and class
54. units that come with the Free Pascal distribution Since there is a difference in the supplied units per operating system we first describe the generic ones then describe those which are operating system specific 9 1 Standard units The following units are standard and are meant to be ported to all platforms supported by Free Pascal A brief description of each unit is also given charset A unit to provide mapping of character sets cmem Using this unit replaces the Free Pascal memory manager with the memory manager of the C library crt This unit is similar to the unit of the same name of Turbo Pascal It implements writing to the console in color moving the text cursor around and reading from the keyboard dos This unit provides basic routines for accessing the operating system This includes file search ing environment variables access getting the operating system version getting and setting the system time It is to note that some of these routines are duplicated in functionality in the sysutils unit dynlibs Provides cross platform access to loading dynamical libraries getopts This unit gives you the GNU getopts command line arguments handling mechanism It also supports long options graph This unit is deprecated This unit provides basic graphics handling with routines to draw lines on the screen display text etc It provides the same functions as the Turbo Pascal unit heaptre a unit which debugs the heap usage When th
55. unless debugging informa tion is generated for the program Directories Presents a dialog where the various directories needed by the compiler can be set These directories will be used when a program or unit is compiled Browser Presents a dialog where the browser options can be set The browser options affect the behaviour of the symbol browser of the IDE Tools Presents a dialog to configure the tools menu For more information see section 6 10 5 page 62 Environment Presents a dialog to configure the behaviour of the IDE A sub menu is presented with the various aspects of the IDE Preferences General preferences such as whether to save files automatically or not and which files should be saved The video mode can also be set here Editor Controls various aspects of the edit windows 45 CHAPTER 6 THE IDE CodeComplete Used to set the words which can be automatically completed when typing in the editor windows Codetemplates Used to define code templates which can be inserted in an edit window Desktop Used to control the behaviour of the desktop i e several features can be switched on or off Keyboard Mouse Can be used to select the cut copy paste convention control the actions of the mouse and to assign commands to various mouse actions Learn keys Let the IDE learn keystrokes to be assigned to various commands This is useful mostly on LINUX and Unix like platforms where the actual keys sent to the IDE
56. warns that 1t will not reload the unit because it is already in a second recompile Flag for reload arg1 When you use the vu flag the compiler warns that it has to reload the unit Forced reloading When you use the vu flag the compiler warns that it is reloading the unit be cause it was required Previous state of arg1 arg2 When you use the vu flag the compiler shows the previous state of the unit Already compiling arg1 setting second compile When you use the vu flag the compiler warns that it is starting to recompile a unit for the second time This can happen with interdependent units Loading unit argl When you use the vu flag the compiler warns that it starts loading the unit Finished loading unit argl When you use the vu flag the compiler warns that it finished loading the unit Registering new unit argl When you use the vu flag the compiler warns that it has found a new unit and is registering it in the internal lists Re resolving unit argl When you use the vu flag the compiler warns that it has to recalculate the internal data of the unit Skipping re resolving unit arg still loading used units When you use the vu flag the compiler warns that it is skipping the recalculation of the internal data of the unit because there is no data to recalculate Unloading resource unit arg1 not needed When you use the vu flag the compiler warns that it is unloading the resource handling unit since no resource
57. 232 the first character of a command line option can be a character instead of a character So S is equivalent to S 6 1 3 The IDE screen After start up the screen of the IDE can look like figure 6 1 Figure 6 1 The IDE screen immediately after startup At the top of the screen the menu bar is visible at the bottom the status bar The empty space between them is called the desktop The status bar shows the keyboard shortcuts for frequently used commands and allows quick access to these commands by clicking them with the mouse At the right edge of the status bar the current amount of unused memory is displayed This is only an indication since the IDE tries to allocate more memory from the operating system if it runs out of memory The menu provides access to all of the IDE s functionality and at the right edge of the menu a clock is displayed The IDE can be exited by selecting FilelExit in the menu or by pressing ALT X Remark If a file fp ans is found in the current directory then it is loaded and used to paint the background This file should contain ANSI drawing commands to draw on a screen 1 FilelExit means select the item Exit in the menu File 36 CHAPTER 6 THE IDE 6 2 Navigating in the IDE The IDE can be navigated both with the keyboard and with a mouse if the system is equipped with a mouse 6 2 1 Using the keyboard All functionality of the IDE is available through use of t
58. 6 4 2 The File menu The File menu contains all menu items that allow the user to load and save files as well as to exit the IDE New Opens a new empty editor window New from template Prompts for a template to be used asks to fill in any parameters and then starts a new editor window with the template Open F3 Presents a file selection dialog and opens the selected file in a new editor window Print print the contents of the current edit window Print setup set up the printer properties Reload Reload a file from disk Save F2 Saves the contents of the current edit window with the current filename If the current edit window does not yet have a filename a dialog is presented to enter a new filename 41 CHAPTER 6 THE IDE Save as Presents a dialog in which a filename can be entered The current window s contents are then saved to this new filename and the filename is stored for further save actions Save all Saves the contents of all edit windows Change dir Presents a dialog in which a directory can be selected The current working directory is then changed to the selected directory Command shell Executes a command shell After the shell is exited the IDE resumes Which command shell is executed depends on the system Exit ALT X Exits the IDE If any unsaved files are in the editor the IDE will ask if these files should be saved Under the Exit menu appear some filenames of recently used files These
59. 86_64 suse linux gdb The actual prompt will vary depending on your operating system and installed version of gdb of course To start the program you can use the run command You can optionally specify command line parameters which will then be fed to your program for example gdb run option anotheroption needed_argument If your program runs without problems gdb will inform you of this and return the exit code of your program If the exit code was zero then the message Program exited normally is displayed If something went wrong a segmentation fault or such gdb will stop the execution of your program and inform you of this with an appropriate message You can then use the other gdb commands to see what happened Alternatively you can instruct gdb to stop at a certain point in your program with the break command Here is a short list of gdb commands which you are likely to need when debugging your program quit Exit the debugger kill Stop a running program help Give help on all gdb commands file Load a new program into the debugger 116 CHAPTER 10 DEBUGGING YOUR PROGRAMS directory Add a new directory to the search path for source files 33 Remark My copy of gdb needs to be added explicitly to the search path otherwise it doesn t find the sources list List the program sources in chunks of 10 lines As an option you can specify a line number or function name break Set a breakp
60. B expressions Line Line number in the file where to stop Only for breakpoints of type file line Ignore count The number of times the breakpoint will be ignored before the program stops Remark 1 Because the IDE uses GDB to do its debugging it is necessary to enter all expressions in uppercase 2 Expressions that reference memory locations should be no longer than 16 bytes on LINUX or go32v2 on an Intel processor since the Intel processor s debug registers are used to monitor these locations 3 Memory location watches will not function on Win32 unless a special patch is applied 6 9 2 Using watches When debugging information is compiled in the program watches can be used Watches are expres sions which can be evaluated by the IDE and shown in a separate window When program execution stops e g at a breakpoint all watches will be evaluated and their current values will be shown Setting a new watch can be done with the DebuglAdd watch menu command or by pressing CTRL F7 When this is done the watch property dialog appears and a new expression can be entered The watch property dialog is shown in figure 6 13 In the dialog the expression can be entered Any possible previous value and current value are shown Remark Because the IDE uses GDB to do its debugging it is necessary to enter all expressions in uppercase in FREEBSD A list of watches and their present value is available in the watches window which can
61. Because free is a normal method of a class it cannot be called from a class method Error Constant and CASE types do not match One of the labels is not of the same type as the case variable Error The symbol can t be exported from a library You can only export procedures and func tions when you write a library You cannot export variables or constants Warning An inherited method is hidden by argl1 A method that is declared virtual in a parent class should be overridden in the descendant class with the override directive If you don t specify the override directive you will hide the parent method you will not override it Error There is no method in an ancestor class to be overridden arg1 You are trying to override a virtual method of a parent class that does not exist Error No member is provided to access property You specified no read directive for a prop erty Warning Stored property directive is not yet implemented This message is no longer used as the stored directive has been implemented Error Illegal symbol for property access There is an error in the read or write directives for an array property When you declare an array property you can only access it with procedures and functions The following code would cause such an error tmyobject class i integer property x i integer integer read I write i Error Cannot access a protected field of an object here Fields that are declared ina protected se
62. C lt x gt Code generation options Ca lt x gt Select ABI see fpc i for possible values Cb Generate big endian code CC lt x gt Set default calling convention to lt x gt CD Create also dynamic library not supported Ce Compilation with emulated floating point opcodes Cf lt x gt Select fpu instruction set to use see fpc i for possible values CF lt x gt Minimal floating point constant precision default 32 64 Cg Generate PIC code Ch lt n gt lt n gt bytes heap between 1023 and 67107840 EL IO checking Cn Omit linking stage Co Check overflow of integer operations CO Check for possible overflow of integer operations Cp lt x gt Select instruction set see fpc i for possible values CP lt x gt lt y gt packing settings CPPACKSET lt y gt lt y gt set allocation 0 1 or DEFAULT or NORMAL 2 4 and 8 Cr Range checking 121 APPENDIX A ALPHABETICAL LISTING OF COMMAND LINE OPTIONS CR Verify object method call validity Cs lt n gt Set stack size to lt n gt EE Stack checking CX Create also smartlinked library d lt x gt Defines the symbol lt x gt p Generate a DEF file Dd lt x gt Set description to lt x gt Dv lt x gt Set DLL version to lt x gt e lt x gt Set path to executable E Same as Cn fPIC Same as Cg F lt x gt Set file names and paths Fa lt x gt y for a program load units lt x gt an
63. CHAPTER 6 THE IDE 6 10 7 Building a command line dialog box When defining a tool it is possible to show a dialog to the user asking for additional arguments using the SPROMPT filename command macro The Free Pascal distribution contains some ready made dialogs such as a grep dialog a cvs checkout dialog and a cvs check in dialog The files for these dialogs are in the binary directory and have an extension tdf In this section the file format for the dialog description file is explained The format of this file resembles a windows INI file where each section in the file describes an element or control in the dialog An OK and a Cancel button will be added to the bottom of the dialog so these should not be specified in the dialog definition A special section is the Main section It describes how the result of the dialog will be passed to the command line and the total size of the dialog Keywords that contain a string value should have the string value enclosed in double quotes as in Title Dialog title The Main section should contain the following keywords Title The title of the dialog This will appear in the frame title of the dialog The string should be enclosed in quotes Size The size of the dialog this is formatted as Cols Rows so Size 59 9 means the dialog is 59 characters wide and 9 lines high This size does not include the border of the dialog CommandLine specifies how th
64. Error Threadvars can be only static or global Threadvars must be static or global you can t de clare a thread local to a procedure Local variables are always local to a thread because every thread has its own stack and local variables are stored on the stack Fatal Direct assembler not supported for binary output format You can t use direct assembler when using a binary writer Choose an other output format or use another assembler reader Warning Don t load OBJPAS unit manually use modeobj fpc or mode delphi instead You are trying to load the ObjPas unit manually from a uses clause This is not a good idea Use the SMODE OBJFPC or Smode delphi directives which load the unit automatically Error OVERRIDE can t be used in objects Override is not supported for objects use virtual instead to override a method of a parent object Error Data types which require initialization finalization can t be used in variant records Some data types e g ansist ring need initialization finalization code which is implicitly gener ated by the compiler Such data types can t be used in the variant part of a record Error Resourcestrings can be only static or global Resourcestring can not be declared local only global or using the static directive Error Exit with argument can t be used here An exit statement with an argument for the return value can t be used here This can happen for example intry except ortry finally blocks
65. Free Pascal User s Guide User s Guide for Free Pascal Version 2 2 2 Document version 2 2 June 2008 Micha l Van Canneyt Florian Klampfl Contents 1 Introduction UL Abo utthisdocument ii ee eR ee a da L2 About he compiler s ic caros sario a a ac e 1 3 Getting MOTE information s s ec ee eh ee Ee ee eee ee a 2 Installing the compiler 2 1 Before Installation Requirements e e ALI Hardware requirements o c ce enio ew ka ESE EHR EES we 21 2 Soliwarerequiremenis coco ooo ea eee ee Winder DOS snc oS oe ce oe 8 A ee PA A GOS See me E Under UNDE 25 45 5a 64 4 des eee A oe Pee Pd ee ee a Under Windows oo oscila RR e a Cri ara A a a Under MacOS X ooo ummm A Ee 2 2 Installing thecompil t lt coco A ee A A eo 2 21 Inst lling wider Windows s 6005 4 0606408 ne eee Pa de ew 2 2 2 Installing under DOS or OS 2 ee a ee eee Mandatory installation steps 2 o es lt lt eee Optional Installation The coprocessor emulation 22 0 Installing underline s oe 062450545 2 ee ewe ae cea san Mandatory installation steps 2 2 ee ee ee 2 3 Optional configuration steps css copa espa SE e 28 Pelo tompa ce GR a RR DE Pe Re LG ee eee ea 2 VESTIR COROS 5 a ess ek eS ee SPE oer See See 3 Compiler usage Sl o oi eR Ree AN 3 1 1 Command line files crece EE meri beda eee ee Il Unt Res og ee eee de Ee eo ae Ee oR Pa Ee a Sl AA IA LLE DEDOS lt
66. L T Insert line CTRL N Toggle insert mode INSERT CTRL V 86 CHAPTER 6 THE IDE Table 6 8 Block commands Command Shortcut key Alternative Goto Beginning of selected text CTRL Q B Goto end of selected text CTRL Q K Select current line CTRL K L Print selected text CTRL K P Select current word CTRL K T Delete selected text CTRL DEL CTRL K Y Copy selected text to cursor posi CTRL K C tion Move selected text to cursor posi CTRL K V tion Copy selected text to clipboard CTRL INS Move selected text to the clipboard SHIFT DEL Indent block one column CTRL K I Unindent block one column CTRL K U Insert text from clipboard SHIFT INSERT Insert file CTRL K R Write selected text to file CTRL K W Uppercase current block CTRL K N Lowercase current block CTRL K O Uppercase word CTRL K E Lowercase word CTRL K F 87 CHAPTER 6 THE IDE Table 6 9 Change selection Command Shortcut key Alternative Mark beginning of selected text CTRL K B Mark end of selected text CTRL K K Remove selection CTRL K Y Extend selection one char to the left Extend selection one char to the right Extend selection to the beginning of the line Extend selection to the end of the line Extend selection to the same col umn in the last row Extend selection to the same col umn in the next row Extend selection to the end of the line Extend selection one word to the left Extend selection one word to the right Extend selection one page up
67. M VALUE Specify alignment of structures and code PARAM determines what should be aligned VALUE specifies the alignment boundary See the Programmer s Guide for a description of the possible values g Optimize for size try to generate smaller code G Optimize for time try to generate faster code default r Keep certain variables in registers experimental use with caution u Uncertain optimizations 1 Level 1 optimizations quick optimizations 2 Level 2 optimizations 01 plus some slower optimizations 3 Level 3 optimizations 02 plus 0u 27 CHAPTER 5 COMPILER CONFIGURATION Pn Intel only Specify processor n can be one of 1 Optimize for 386 486 2 Optimize for Pentium PentiumMMX tm 3 Optimizations for PentiumPro PII Cyrix 6x86 K6 tm The exact effect of these optimizations can be found in the Programmers guide oxxx Use xxx as the name of the output file executable For use only with programs The output filename can contain a path and if it does it will override any previous FE setting If the output filename does not contain a path the FE setting is observed pg Generate profiler code for gprof This will define the symbol FPC_PROFILE which can be used in conditional defines s Do not call the assembler and linker Instead the compiler writes a script PPAS BAT under DOS or ppas sh under LINUX which can then be executed to produce an executable This can be used to speed up the com
68. PPENDIX D RUN TIME ERRORS 17 Cannot rename across drives You cannot rename a file such that it would end up on another disk or partition 100 Disk read error An error occurred when reading from disk Typically happens when you try to read past the end of a file 101 Disk write error Reported when the disk is full and you re trying to write to it 102 File not assigned This is reported by Reset Rewrite Append Rename and Erase if you call them with an unassigned file as a parameter 103 File not open Reported by the following functions Close Read Write Seek EOf FilePos FileSize Flush BlockRead and BlockWrite ifthe file is not open 104 File not open for input Reported by Read BlockRead Eof Eoln SeekEof orSeekEoln 1f the file is not opened with Reset 105 File not open for output Reported by write if a text file isn t opened with Rewrite 106 Invalid numeric format Reported when a non numeric value is read from a text file and a numeric value was expected 150 Disk is write protected Critical error 151 Bad drive request struct length Critical error 152 Drive not ready Critical error 154 CRC error in data Critical error 156 Disk seek error Critical error 157 Unknown media type Critical error 158 Sector Not Found Critical error 159 Printer out of paper Critical error 160 Device write fault Critical error 161 Device read fault Critical error 162 Hardware f
69. S the Edit menu has two additional entries The IDE maintains a separate clipboard which does not share its contents with the WINDOWS clipboard To access the WINDOWS clipboard the following two entries are also present Copy to Windows Copy the selection to the WINDOWS clipboard Paste from Windows Insert the contents of the WINDOWS clipboard if it contains text in the edit window at the current cursor position 42 CHAPTER 6 THE IDE 6 4 4 The Search menu The Search menu provides access to the search and replace dialogs as well as access to the symbol browser of the IDE Find CTRL Q F Presents the search dialog A search text can be entered and when the dialog is closed the entered text is searched for in the active window If the text is found it will be selected Replace CTRL Q A Presents the search and replace dialog After the dialog is closed the search text will be replaced by the replace text in the active window Search again CTRL L Repeats the last search or search and replace action using the same pa rameters Go to line number ALT G Prompts for a line number and then jumps to this line number When the program and units are compiled with browse information then the following menu entries are also enabled Find procedure Not yet implemented Objects Asks for the name of an object and opens a browse window for this object Modules Asks for the name of a module and opens a browse window for
70. Selected assembler reader not supported The selected assembler reader with SASMMODE xxx is not supported The compiler can be compiled with or without support for a particular assembler reader Error Procedure directive argl has conflicts with other directives You specified a procedure directive that conflicts with other directives For instance cdecl and pascal are mutually exclusive Error Calling convention doesn t match forward This error happens when you declare a func tion or procedure with e g cdecl but omit this directive in the implementation or vice versa The calling convention is part of the function declaration and must be repeated in the function definition Error Property can t have a default value Set properties or indexed properties cannot have a de fault value Error The default value of a property must be constant The value of ade fault declared prop erty must be known at compile time The value you specified is only known at run time This happens e g if you specify a variable name as a default value Error Symbol can t be published can be only a class Only class type variables can be ina published section of a class if they are not declared as a property Error This kind of property can t be published Properties in a published section cannot be array properties They must be moved to public sections Properties in a published section must be an ordinal type a real type strings or sets Error
71. Static libraries Tries to link in units in static libraries option XS on the command line Smart libraries Tries to link in units in smart linked libraries option XX on the command line 6 11 6 Memory sizes The memory sizes dialog reachable via options Memory sizes permits the entry of the memory sizes for the project The memory sizes dialog is shown in figure 6 30 The following sizes can be entered 75 CHAPTER 6 THE IDE Figure 6 30 The memory sizes dialog 131072 Bap size 2097152 Stack size Sets the size of the stack in bytes option Cs on the command line This size may be ignored on some systems Heap size Sets the size of the heap in bytes option Ch on the command line Note that the heap grows dynamically as much as the OS allows 6 11 7 Debug options In the debug options dialog reachable via OptionsIDebugger some options for inclusion of debug information in the binary can be set it is also possible to add additional compiler options in this dialog The debug options dialog is shown in figure 6 31 Figure 6 31 The debug options dialog 3 Skip debug information generation d l u Profiling Switches se Another tty for Debuggee The following options can be set 76 CHAPTER 6 THE IDE Debugging information tells the compiler which debug information should be compiled in One of the following options can be chosen Strip all debug symbols from executable Wil
72. This section lists all messages that can be displayed if the code generator encounters an error condi tion Error Parameter list size exceeds 65535 bytes The I386 processor limits the parameter list to 65535 bytes The RET instruction causes this Error File types must be var parameters You cannot specify files as value parameters i e they must always be declared var parameters Error The use of a far pointer isn t allowed there Free Pascal doesn t support far pointers so you cannot take the address of an expression which has a far reference as a result The mem construct has a far reference as a result so the following code will produce this error var p pointer p mem a000 000 Error EXPORT declared functions can t be called No longer in use Warning Possible illegal call of constructor or destructor The compiler detected that a construc tor or destructor is called within a a method This will probably lead to problems since con structors destructors require parameters on entry Note Inefficient code Your statement seems dubious to the compiler Warning unreachable code You specified a construct which will never be executed Example 154 APPENDIX C COMPILER MESSAGES while false do begin code end Error Abstract methods can t be called directly You cannot call an abstract method directly In stead you must call an overriding child method because an abstract method isn t i
73. When checked the list of codecompletion words is saved On by default CodeTemplates When checked the defined code templates are saved On by default Remark The format of the desktop file changes between editor versions So when installing a new version it may be necessary to delete the fp dsk files wherever the IDE searches for them 6 12 3 The Editor Several aspects of the editor window behaviour can be set in this dialog The editor preferences dialog is shown in figure 6 35 Figure 6 35 The editor preferences dialog I1 Default Editor Options ditor options ij Create backup files pas pp gt inc makex makex fpcmake loc The following elements can be set in the editor preferences dialog Create backup files Whenever an editor file is saved a backup is made of the old file On by default Insert mode Start with insert mode 80 CHAPTER 6 THE IDE Auto indent mode Smart indenting is on This means that pressing ENTER will position the cursor on the next line in the same column where text starts on the current line On by default Use tab characters When the tab key is pressed use a tab character Normally when the tab key is pressed spaces are inserted When this option is checked tab characters will be inserted instead Off by default Backspace unindents Pressing the BKSP key will unindent if the beginning of the text on the current line is reached instead of deleting just the previous c
74. a operator Fatal Including include files exceeds a depth of 16 When including include files the files have been nested to a level of 16 The compiler will expand no further since this may be a sign that recursion is used Fatal Too many levels of PUSH A maximum of 20 levels is allowed This error occurs only in mode MacPas Error A POP without a preceding PUSH This error occurs only in mode MacPas Error Macro or compile time variable arg1 does not have any value Thus the conditional com pile time expression cannot be evaluated Error Wrong switch toggle use ON OFF DEFAULT or You need to use ON or OFF or DEFAULT or a or or to toggle the switch 130 APPENDIX C COMPILER MESSAGES Error Mode switch arg1 not allowed here A mode switch has already been encountered or in the case of option Mmacpas a mode switch occurs after UNIT Error Compile time variable or macro arg1 is not defined Thus the conditional compile time expression cannot be evaluated Only in mode MacPas Error UTF 8 code greater than 65535 found Free Pascal handles UTF 8 strings internally as widestrings i e the char codes are limited to 65535 Error Malformed UTF 8 string The given string isn t a valid UTF 8 string UTF 8 signature found using UTF 8 encoding The compiler found a UTF 8 encoding signature Sef bb bf at the beginning of a file so it interprets it as a UTF 8 file Error Compile time expression Want
75. a a a CONTENTS JLS CONECTADO DS or A Rd 20 LLG About long filenames o e ia A e 20 32 COMPllE a propia e a a A a da Ae A iaa 20 ao OMPI AM o ae e eee Oe G 21 o Units libraries and smartlinkinE 2 2 06 5444545 6448 oe wae o vs 21 3 Reducing the size of your program 2 6 ee ee ee ew ee 21 Compiling problems 22 4 1 General problems o s cco cerade wut EA ESR ee Eee 22 4 2 Problems you may encounter under DOS 2 64 05h ee eee ee 22 Compiler configuration 23 5 1 Using the command Ime options oo soso eRe ee ee OES 23 A A ee Re e A le eee e 23 5 1 2 Options lor petting feedback oo be ee p iee ee ee 24 5 1 3 Options concerning files and directories o o 24 5 1 4 Options controlling the kind of output 25 5 1 5 Options concerning the sources language options 29 32 WUsneiieconlguralon Me ss pops a5 pean eS eRe da 31 S24 MEDEE 014 55 he bo coe A rs dee 31 122 MENDEP cras 64 ee RE OH SESE SE eae Ea HG e 5 32 Oued HELSE 24 52 4454 4 8066 A e dd e a de 32 S24 ENDIF os ee o ee Gwe RS A ea ge 32 RS DEFNE don bp be a sere ee aoe eae Ya eS eS 33 ue RUNDEP iooi koe Sea ee dbo e pe RES R e rra meee ee 33 Melee Greys oot Poe eee eae Oh eee Se ae See Eanes eS 33 Sue RINELUIVA 2205 Si de BOS OES PRES eS owl ei e 33 349 FSBCTON re 4 gee CRS ee DAM ER eae ea ee Ee fe 34 5 3 Vanable substitution in paths kc RR EE eS 34 The IDE 35 6 1 First stepe withthe IDE
76. age Goto previous ALT F7 Goes to the previous message Grep SHIFT F2 Prompts for a regular expression and options to be given to grep and then exe cutes grep with the given expression and options For this to work the grep program must be installed on the system and be in a directory that is in the PATH For more information see section 6 10 2 page 60 Calculator Displays the calculator For more information see section 6 10 4 page 61 Ascii table Displays the ASCII table For more information see section 6 10 3 page 60 6 4 9 The Options menu The Options menu is the entry point for all dialogs that are used to set options for the compiler and the IDE as well as the user preferences Mode Presents a dialog to set the current mode of the compiler The current mode is shown at the right of the menu entry For more information see section 6 11 8 page 77 Compiler Presents a dialog that can be used to set common compiler options These options will be used when compiling a program or unit Memory sizes Presents a dialog where the stack size and the heap size for the program can be set These options will be used when compiling a program Linker Presents a dialog where some linker options can be set These options will be used when a program or library is compiled Debugger Presents a dialog where the debugging options can be set These options are used when compiling units or programs Note that the debugger will not work
77. ailure Critical error 200 Division by zero The application attempted to divide a number by zero 201 Range check error If you compiled your program with range checking on then you can get this error in the following cases 1 An array was accessed with an index outside its declared range 2 Trying to assign a value to a variable outside its range for instance an enumerated type 202 Stack overflow error The stack has grown beyond its maximum size in which case the size of local variables should be reduced to avoid this error or the stack has become corrupt This error is only reported when stack checking is enabled 203 Heap overflow error The heap has grown beyond its boundaries This is caused when trying to allocate memory explicitly with New GetMem or ReallocMen or when a class or object instance is created and no memory is left Please note that by default Free Pascal provides a growing heap i e the heap will try to allocate more memory if needed However if the heap has reached the maximum size allowed by the operating system or hardware then you will get this error 169 APPENDIX D RUN TIME ERRORS 204 Invalid pointer operation You will get this if you call Dispose or Freemem with an invalid pointer notably Ni1 205 Floating point overflow You are trying to use or produce real numbers that are too large 206 Floating point underflow You are trying to use or produce real numbers that are too small 207 I
78. alized This message is displayed if the com piler thinks that a variable will be used i e it appears in the right hand side of an expression when it was not initialized first i e it did not appear in the left hand side of an assigment Hint Variable arg1 does not seem to be initialized This message is displayed if the compiler thinks that a variable will be used i e it appears in the right hand side of an expression when it was not initialized first i e t did not appear in the left hand side of an assigment Warning Function result variable does not seem to initialized This message is displayed if the compiler thinks that the function result variable will be used i e it appears in the right hand side of an expression before it is initialized 1 e before it appeared in the left hand side of an assigment Hint Function result variable does not seem to be initialized This message is displayed if the com piler thinks that the function result variable will be used i e it appears in the right hand side of an expression before it is initialized i e it appears in the left hand side of an assigment Warning Variable arg1 read but nowhere assigned You have read the value of a variable but nowhere assigned a value to it Hint Found abstract method arg1 When getting a warning about constructing a class object with abstract methods you get this hint to assist you in finding the affected method C 6 Code generator messages
79. alog is called by the menu item Options Environment Preferences The pref erences dialog is shown in figure 6 33 Video mode The drop down list at the top of the dialog allows selecting a video mode The available video modes depend on the system on which the IDE is running Remark 1 The video mode must be selected by pressing space or clicking on it If the drop down list is opened while leaving the dialog the new video mode will not be applied 2 For the DOS version of the IDE the following should be noted When using VESA modes the display refresh rate may be very low On older graphics card 1998 and before it is possible to use the UniVBE driver from SciTech Desktop File Specifies where the desktop file is saved the current directory or the directory where the config file was found 5It can be downloaded from http www informatik fh muenchen de ifw98223 vbehz htm 78 CHAPTER 6 THE IDE Auto save Here it is possible to set which files are saved when a program is run or when the IDE is exited Editor files The contents of all open edit windows will be saved Environment The current environment settings will be saved Desktop The desktop file with all desktop settings open windows history lists breakpoints etc will be saved Options Some special behaviours of the IDE can be specified here Auto track source Close on go to source When checked the messages window is closed when the go to source li
80. aluated in 64 bit arith metic which is slower than normal 32 bit arithmetic You can avoid this by typecasting one operand so it matches the result type of the other one Warning Mixing signed expressions and cardinals here may cause a range check error If you use a binary operator and or xor and one of the operands is a longword while the other one is a signed expression then if range checking is turned on you may get a range check error because in such a case both operands are converted to longword before the operation is carried out You can avoid this by typecasting one operand so it matches the result type of the other one Error Typecast has different size argl gt arg2 in assignment Type casting to a type with a dif ferent size is not allowed when the variable is used in an assignment Error enums with assignments can t be used as array index When you declared an enumeration type which has C like assignments such as in the following Tenum a b e 5 you cannot use it as the index of an array Error Class or Object types arg1 and arg2 are not related There is a typecast from one class or object to another while the class object are not related This will probably lead to errors Warning Class types arg1 and arg2 are not related There is a typecast from one class to another while the classes are not related This will probably lead to errors Error Class or interface type expected but got arg1 The
81. an be used to activate the next window in the list of windows while Window Previous will select the previous window e If the window has a number in the upper right corner it can be activated by pressing ALT lt NUMBER gt Pressing ALT 0 will pop up a dialog with all available windows which allows a quick activation of windows which don t have a number The windows can be ordered and placed on the IDE desktop by zooming and resizing them with the mouse or keyboard This is a time consuming task and particularly difficult with the keyboard Instead the menu items WindowITile and Window Cascade can be used Tile will divide the whole desktop space evenly between all resizable windows Cascade puts all the windows in a cascaded arrangement In very rare cases the screen of the IDE may become mixed up In this case the whole IDE screen can be refreshed by selecting the menu item Windowl Refresh display 6 3 4 Dialog windows In many cases the IDE displays a dialog window to get user input The main difference to normal windows is that other windows cannot be activated while a dialog is active Also the menu is not accessible while in a dialog This behaviour is called modal To activate another window the modal window or dialog must be closed first A typical dialog window is shown in figure 6 3 6 4 The Menu The main menu the gray bar at the top of the IDE provides access to all the functionality of the IDE It al
82. and line Compiler mode select the appropriate compiler mode Free Pascal Dialect The default Free Pascal compiler mode FPC Object pascal extensions on Enables the use of classes and exceptions Sd see page 5 1 5 on the command line Turbo pascal compatible Try to be more Turbo Pascal compatible So see page 5 1 5 on the command line Delphi compatible Try to be more Delphicompatible Sd see page 5 1 5 on the command line 70 CHAPTER 6 THE IDE Macintosh Pascal dialect Try to be Macintosh pascal compatible The code generation tab of the compiler options dialog is shown in figure 6 24 Figure 6 24 The code generation options tab Compiler Switches Code generation Run time checks BI Range checking In the code generation dialog the following options can be set Run time checks Controls what run time checking code is generated If such a check fails a run time error is generated The following checking code can be generated Range checking Checks the results of enumeration and subset type operations Cr see page 5 1 4 command line option Stack checking Checks whether the stack limit is not reached Cs see page 5 1 4 command line option VO checking Checks the result of IO operations Ci see page 5 1 4 command line option Integer overflow checking Checks the result of integer operations Co see page 5 1 4 command line option Object method call checking Check the va
83. anguage constructs are 1 Dynamic methods are actually the same as virtual 2 Const for a parameter to a procedure does not necessarily mean that the variable or value is passed by reference 3 Packages are not supported 95 CHAPTER 7 PORTING AND PORTABLE CODE There are some inline assembler constructs which are not supported and since Free Pascal is designed to be platform independent it is quite unlikely that these constructs will be supported in the future Note that the Mob j fpc mode switch is to a large degree Delphi compatible but is more strict than Delphi The most notable differences are 1 Parameters or local variables of methods cannot have the same names as properties of the class in which they are implemented 2 The address operator is needed when assigning procedural variables or event handlers 3 AnsiStrings are not switched on by default 7 3 2 Missing calls API incompatibilities Delphi is heavily bound to Windows Because of this it introduced a lot of Windows isms in the API e g file searching and opening loading libraries Free Pascal was designed to be portable so things that are very Windows specific are missing al though the Free Pascal team tries to minimize this The following are the main points that should be considered e By default Free Pascal generates console applications This means that you must explicitly enable the GUI application type for Windows SAPPTYPE GUI
84. atch CTRL F7 Adds a watch A watch is an expression that can be evaluated by the IDE and will be shown in a special window Usually this is the content of some variable Watches Shows the current list of watches in a separate window Breakpoint CTRL F8 Sets a breakpoint at the current line When debugging program execution will stop at this breakpoint Breakpoint list Shows the current list of breakpoints in a separate window Evaluate Call stack CTRL F3 Shows the call stack The call stack is the list of addresses and filenames and line numbers if this information was compiled in of procedures that are currently being called by the running program Disassemble Shows the call stack Registers Shows the current content of the CPU registers Floating point unit Shows the current content of the FPU registers Vector unit Shows the current content of the MMX or equivalent registers GDB window Shows the GDB debugger console This can be used to interact with the debugger directly here arbitrary GDB commands can be typed and the result will be shown in the window 44 CHAPTER 6 THE IDE 6 4 8 The Tools menu The Tools menu defines some standard tools If new tools are defined by the user they are ap pended to this menu as well Messages F11 Shows the messages window This window contains the output from one of the tools For more information see section 6 10 1 page 59 Goto next ALT F8 Goes to the next mess
85. ath not found Reported by the directory handling routines when a path does not exist or is in valid Also reported when trying to access a non existent file 4 Too many open files The maximum number of files currently opened by your process has been reached Certain operating systems limit the number of files which can be opened concurrently and this error can occur when this limit has been reached 5 File access denied Permission to access the file is denied This error might be caused by one of several reasons e Trying to open for writing a file which is read only or which is actually a directory e File is currently locked or used by another process e Trying to create a new file or directory while a file or directory of the same name already exists e Trying to read from a file which was opened in write only mode e Trying to write from a file which was opened in read only mode e Trying to remove a directory or file while it is not possible e No permission to access the file or directory 6 Invalid file handle If this happens the file variable you are using is trashed it indicates that your memory is corrupted 12 Invalid file access code Reported when a reset or rewrite is called with an invalid FileMode value 15 Invalid drive number The number given to the Getdir or ChDir function specifies a non existent disk 16 Cannot remove current directory Reported when trying to remove the currently active direc tory 168 A
86. atibility oldlinux This unit is deprecated This unit provides access to the LINUX operating system It pro vides most file and I O handling routines that you may need It implements most of the standard C library constructs that you will find on a Unix system It is recommended however that you use the baseunix unixtype and unix units They are more portable ports This implements the various port constructs These are provided for compatibility only and it is not recommended to use them extensively Programs using this construct must be run as ruit or setuid root and are a serious security risk on your system termio Terminal control routines which are compatible to the C library routines unix Extended Unix operations unixtype All types used commonly on Unix platforms 9 5 Under OS 2 doscalls Interface to doscalls dll dive Interface to dive dll emx Provides access to the EMX extender pm Interface units for the program manager functions 113 CHAPTER 9 UNITS THAT COME WITH FREE PASCAL viocalls Interface to viocalls dll screen handling library moucalls Interface to moucalls dll mouse handling library kbdcalls Interface to kbdcalls dll keyboard handling library moncalls Interface to moncalls dll monitoring handling library 9 6 Unit availability Standard unit availability for each of the supported platforms is given in the FAQ Knowledge base 114 Chapter 10 Debugging your programs Free Pascal
87. bles declared as threadvar can not be initialized with a default value The variables will always be filled with zero at the start of a new thread Error Message directive is only allowed in Classes The message directive is only supported for Class types Error Procedure or Function expected A class method can only be specified for procedures and functions Warning Calling convention directive ignored argl Some calling conventions are supported only by certain CPUs Le most non i386 ports support only the standard ABI calling conven tion of the CPU Error REINTRODUCE can t be used in objects reintroduce is not supported for objects Error Each argument must have its own location If locations for arguments are specified explic itly as it is required by some syscall conventions each argument must have its own location Things like procedure p i j longint rl aren t allowed Error Each argument must have an explicit location If one argument has an explicit argument location all arguments of a procedure must have one Error Unknown argument location The location specified for an argument isn t recognized by the compiler Error 32 Bit Integer or pointer variable expected The libbase for MorphOS AmigaOS can be given only as 1ongint dword or any pointer variable Error Goto statements aren t allowed between different procedures It isn t allowed to use goto statements referencing labels outside the current p
88. c 2 2 units i386 linux or when cross compiling usr local lib fpc 2 2 units i386 win32 The Fu option accepts a single wildcard which will be replaced by all directories found on that location but not the location itself For example given the directories rt fol units i386 linux units i386 linux packages base packages extra the command CHAPTER 3 COMPILER USAGE fpc Fu x units i386 linux will have the same effect as fpc Furtl units i386 linux Fufcl units i386 linux since both the rtl and fcl directories contain further units i386 linux subdirectories The packages directory will not be added since it doesn t contain a units i386 linux subdirectory The following command fpc Fu units i386 linux x will match any directory below the units i386 linux directory but will not match the units i386 linux directory itself so you should add it manually if you want the compiler to look for files in this directory as well fpc Fu units i386 linux Fu units i386 linux x begin verbatim Note that for optimization the compiler will drop any non existing paths from the search path i e th xistence of the path after wildcard and environment variable expansion will be tested You can see what paths the compiler will search by giving the compiler the var vu option On systems where filenames are case sensitive such as unix and linux the compiler will beg
89. cal you can specify a return value for a func tion when using the exit statement This error occurs when you try to do this with a proce dure Procedures cannot return a value Error constructors and destructors must be methods You re declaring a procedure as destructor or constructor when the procedure isn t a class method Error Operator is not overloaded You re trying to use an overloaded operator when it is not over loaded for this type Error Impossible to overload assignment for equal types You can not overload assignment for types that the compiler considers as equal Error Impossible operator overload The combination of operator arguments and return type are incompatible Error Re raise isn t possible there You are trying to re raise an exception where it is not allowed You can only re raise exceptions in an except block Error The extended syntax of new or dispose isn t allowed for a class You cannot generate an instance of a class with the extended syntax of new The constructor must be used for that For the same reason you cannot call dispose to de allocate an instance of a class the destructor must be used for that 136 APPENDIX C COMPILER MESSAGES Error Procedure overloading is switched off When using the So switch procedure overloading 1s switched off Turbo Pascal does not support function overloading Error It is not possible to overload this operator Related overloadable operators if
90. can be entered Text to find The text to be searched for If a block was active when the dialog was started the first line of this block is proposed Case sensitive When checked the search is case sensitive Whole words only When checked the search text must appear in the text as a complete word Direction The direction in which the search must be conducted starting from the specified origin Scope Specifies if the search should be on the whole file or just the selected text Origin Specifies if the search should start from the cursor position or the start of the scope CHAPTER 6 THE IDE Figure 6 7 The search dialog I T Opt ions Direction Scope After the dialog has closed the search is performed using the given options A search can be repeated using the same options in one of 2 ways 1 Select SearchlSearch again from the menu 2 Press CTRL L It is also possible to replace occurrences of a text with another text This can be done in a similar manner to searching for a text 1 Select SearchlReplace from the menu 2 Press CTRL Q A A dialog similar to the search dialog will pop up as shown in figure 6 8 Figure 6 8 The replace dialog A L 1 ev text HS tlk Direction ou aa E In this dialog in addition to the things that can be filled in in the search dialog the following things can be entered CHAPTER 6 THE IDE New text Text that will replace the fou
91. can be used to adjust the double click speed Fast means that the time between two clicks is very short slow means that the time between two mouse clicks can be quite long Reverse mouse buttons the behaviour of the left and right mouse buttons can be swapped by by checking the checkbox this is especially useful for left handed people Ctrl Right mouse button Assigns an action to a right mouse button click while holding the CTRL key pressed Alt right mouse button Assigns an action to right mouse button click while holding the ALT key pressed The following actions can be assigned to CTRL Right mouse button or ALT right mouse button Nothing No action is associated to the event 82 CHAPTER 6 THE IDE Topic search The keyword at the mouse cursor is searched in the help index Go to cursor The program is executed until the line where the mouse cursor is located Breakpoint Set a breakpoint at the mouse cursor position Evaluate Evaluate the value of the variable at the mouse cursor Add watch Add the variable at the mouse cursor to the watch list Browse symbol The symbol at the mouse cursor is displayed in the browser 6 13 The help system More information on how to handle the IDE or about the use of various calls in the RTL explanations regarding the syntax of a Pascal statement can be found in the help system The help system is activated by pressing Fl 6 13 1 Navigating in the help system The help system contains
92. ccurred and there was no exception handler present The sysutils unit installs a default exception handler which catches all exceptions and exits gracefully 219 Invalid typecast Thrown when an invalid typecast is attempted on a class using the as operator This error is also thrown when an object or class is typecast to an invalid class or object and a virtual method of that class or object is called This last error is only detected if the CR compiler option is used 222 Variant dispatch error No dispatch method to call from variant 223 Variant array create The variant array creation failed Usually when there is not enough mem ory 224 Variant is not an array This error occurs when a variant array operation is attempted on a vari ant which is not an array 225 Var Array Bounds check error This error occurs when a variant array index is out of bounds 227 Assertion failed error An assertion failed and no AssertErrorProc procedural variable was installed 229 Safecall error check This error occurs is a safecall check fails and no handler routine is avail able 170 APPENDIX D RUN TIME ERRORS 231 Exception stack corrupted This error occurs when the exception object is retrieved and none 1s available 232 Threads not supported Thread management relies on a separate driver on some operating sys tems notably Unixes The unit with this driver needs to be specified on the uses clause of the program preferably as the f
93. ce and bracketing of operations is not yet supported The result of the calculations can be pasted into the text using the CTRL ENTER keystroke The calculator dialog is shown in figure 6 19 The calculator supports all basic mathematical operations such as addition subtraction division and multiplication They are summarised in table 6 1 Table 6 1 Basic mathematical operations Operation Button Key Add two numbers Subtract two numbers Multiply two numbers Divide two numbers Delete the last typed digit lt BACKSPACE Clear display E C Change the sign Do per cent calculation Get result of operation ENTER But also more sophisticated mathematical operations such as exponentiation and logarithms are sup ported The advanced mathematical operations are shown in table 6 2 61 CHAPTER 6 THE IDE Figure 6 19 The calculator dialog Table 6 2 Advanced mathematical operations Operation Button Key Calculate power x y Calculate the inverse value 1 x Calculate the square root sqr Calculate the natural logarithm log Square the display contents x72 Like many calculators the calculator in the IDE also supports storing a single value in memory and several operations can be done on this memory value The available operations are listed in table 6 3 6 10 5 Adding new tools The tools menu can be extended with any external program which is command line oriented The outp
94. ce between the two units or list the available identifiers in both units The output of unitdiff will go to standard output by default 8 10 3 Options Most of the unitdiff options are not required Defaults will be used in most cases disable arguments Do not check the arguments of functions and procedures The default action is to check them disable private Do not check private fields or methods of classes The default action is to check them disable protected Do not check protected fields or methods of classes The default action is to check them help Emit a short help text and exit 109 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL lang language Set the language for the output file This will mainly set the strings used for the headers in various parts of the documentation files by default they re in English Currently valid options are e de German e fr French e nl Dutch list Display just the list of available identifiers for the unit or units If only one unit is specified on the command line this option is automatically assumed output filename Specify where the output should go The default action is to send the output is sent to standard output the screen sparse Turn on sparse mode Output only the identifier names Do not output types or type de scriptions By default type descriptions are also written 110 Chapter 9 Units that come with Free Pascal Here we list the
95. ced code section Size of initialized data argl bytes Informational message showing the size of the initialized data section Size of uninitialized data argl bytes Informational message showing the size of the uninitialized data section Stack space reserved argl bytes Informational message showing the stack size that the compiler reserved for the executable Stack space committed argl bytes Informational message showing the stack size that the com piler committed for the executable C 9 Unit loading messages This section lists all messages that can occur when the compiler is loading a unit from disk into memory Many of these messages are informational messages Unitsearch argl When you use the vt option the compiler tells you where it tries to find unit files PPU Loading arg1 When the vt switch is used the compiler tells you what units it loads PPU Name argl When you use the vu flag the unit name is shown PPU Flags arg When you use the vu flag the unit flags are shown 158 APPENDIX C COMPILER MESSAGES PPU Cre arg1 When you use the vu flag the unit CRC check is shown PPU Time argl When you use the vu flag the time the unit was compiled is shown PPU File too short The ppufile is too short not all declarations are present PPU Invalid Header no PPU at the begin A unit file contains as the first three bytes the ASCII codes of the characters PPU PPU Invalid Version arg1 This unit file was co
96. cess to the low level opengl functions in WINDOWS winmouse Provides access to the mouse in WINDOWS ole2 Provides access to the OLE capabilities of WINDOWS winsock Provides access to the WINDOWS sockets API Winsock Jedi windows header translations The units containing the Jedi translations of the Windows API headers is also distributed with Free Pascal The names of these units start with jw followed by the name of the particular API 9 4 Under Linux and BSD like platforms baseunix Basic Unix operations basically a subset of the POSIX specification Using this unit should ensure portability across most unix systems clocale This unit initializes the internationalization settings in the sysutils unit with settings ob tained through the C library cthreads This unit should be specified as the first or second unit in the uses clause of your program 1t will use the Posix threads implementation to enable threads in your FPC program cwstrings If widestring routines are used then this unit should be inserted as one of the first units in the uses clause of your program it will initialize the widestring manager in the system unit with routines that use C library functions to handle Widestring conversions and other widestring operations errors Returns a string describing an operating system error code Libc This is the interface to GLibc on a linux 1386 system It will not work for other platforms and 1s in general provided for Kylix comp
97. compile these separately e If the previous two don t work recompile the compiler with a bigger heap You can use the Ch option for this Ch see page 5 1 4 Writing Resource String Table file arg1 This message is shown when the compiler writes the Resource String Table file containing all the resource strings for a program Error Writing Resource String Table file arg1 This message is shown when the compiler en Info Info Info Info Info counters an error when writing the Resource String Table file Fatal Prefix for Fatal Errors Error Prefix for Errors Warning Prefix for Warnings Note Prefix for Notes Hint Prefix for Hints Error Path arg1 does not exist The specified path does not exist Fatal Compilation aborted Compilation was aborted bytes code The size of the generated executable code in bytes bytes data The size of the generated program data in bytes Info Info Info argl warning s issued Total number of warnings issued during compilation arg hint s issued Total number of hints issued during compilation argl note s issued Total number of notes issued during compilation C 2 Scanner messages This section lists the messages that the scanner emits The scanner takes care of the lexical structure of the pascal file i e it tries to find reserved words strings etc It also takes care of directives and conditional compilation handling Fatal Unexpecte
98. compiler expected a class or inter face name but got another type or identifier Error Type argl is not completely defined This error occurs when a type is not complete i e a pointer type which points to an undefined type Warning String literal has more characters than short string length The size of the constant string which is assigned to a shortstring is longer than the maximum size of the shortstring 255 char acters Warning Comparison is always false due to range of values There is a comparison between an unsigned value and a signed constant which is less than zero Because of type promotion the statement will always evaluate to false Explicitly typecast the constant to the correct range to avoid this problem Warning Comparison is always true due to range of values There is a comparison between an unsigned value and a signed constant which is less than zero Because of type promotion the statement will always evaluate to true Explicitly typecast the constant to the correct range to avoid this problem Warning Constructing a class argl with abstract methods An instance of a class is created which contains non implemented abstract methods This will probably lead to a runtime error 211 in the code if that routine is ever called All abstract methods should be overriden Hint The left operand of the IN operator should be byte sized The left operand of the in oper ator is not an ordinal or enumeration which fits withi
99. ction of an object or class declaration cannot be accessed outside the module where the object is defined or outside descendent object methods Error Cannot access a private field of an object here Fields that are declared ina private sec tion of an object or class declaration cannot be accessed outside the module where the class is defined Error Overridden methods must have the same return type arg2 is overriden by arg1 which has another return If you declare overridden methods in a class definition they must have the same return type Error EXPORT declared functions can t be nested You cannot declare a function or procedure within a function or procedure that was declared as an export procedure Error Methods can t be EXPORTed You cannot declare a procedure that is a method for an ob ject as exported Error Call by var for arg no argl has to match exactly Got arg2 expected arg3 When call ing a function declared with var parameters the variables in the function call must be of exactly the same type There is no automatic type conversion 135 APPENDIX C COMPILER MESSAGES Error Class isn t a parent class of the current class When calling inherited methods you are try ing to call a method of a non related class You can only call an inherited method of a parent class Error SELF is only allowed in methods You are trying to use the self parameter outside an ob ject s method Only methods get passed th
100. d using the export and alias directives C 4 Type checking errors This section lists all errors that can occur when type checking is performed Error Type mismatch This can happen in many cases e The variable you re assigning to is of a different type than the expression in the assign ment e You are calling a function or procedure with parameters that are incompatible with the parameters in the function or procedure definition Error Incompatible types got argl expected arg2 There is no conversion possible between the two types Another possiblity is that they are declared in different declarations Var Al Array 1 10 Of Integer A2 Array 1 10 Of Integer Begin Al A2 This statement also gives this error It is due to the strict type checking of Pascal End 146 APPENDIX C COMPILER MESSAGES Error Type mismatch between arg1 and arg2 The types are not equal Error Type identifier expected The identifier is not a type or you forgot to supply a type identifier Error Variable identifier expected This happens when you pass a constant to a routine such as Inc var or Dec when it expects a variable You can only pass variables as arguments to these functions Error Integer expression expected but got arg1 The compiler expects an expression of type integer but gets a different type Error Boolean expression expected but got arg1 The expression must be a boolean type It should be
101. d y before uses is parsed Fc lt x gt Set input codepage to lt x gt FC lt x gt Set RC compiler binary name to lt x gt FD lt x gt Set the directory where to search for compiler utilities Fe lt x gt Redirect error output to lt x gt Ff lt x gt Add lt x gt to framework path Darwin only FE lt x gt Set exe unit output path to lt x gt Fi lt x gt Add lt x gt to include path F1 lt x gt Add lt x gt to library path FL lt x gt Use lt x gt as dynamic linker Fm lt x gt Load unicode conversion table from lt x gt txt in the compiler dir Fo lt x gt Add lt x gt to object path Fr lt x gt Load error message file lt x gt FR lt x gt Set resourc res linker to lt x gt Fu lt x gt Add lt x gt to unit path FU lt x gt Set unit output path to lt x gt overrides FE 9 Generate debug information default format for target gc Generate checks for pointers gh Use heaptrace unit for memory leak corruption debugging gl Use line info unit show more info with backtraces go lt x gt Set debug information options godwarfsets Enable Dwarf set debug information breaks gdb lt 6 5 gp Preserve case in stabs symbol names gs Generate stabs debug information gt Trash local variables to detect uninitialized uses 9v Generates programs traceable with valgrind gw Generate dwarf 2 debug information same as gw2 gw2 Generate dwarf 2 debug information gw3 Generate dwarf 3 debug information P Information iD
102. d end of file This typically happens in one of the following cases e The source file ends before the final end statement This happens mostly when the begin and end statements aren t balanced e An include file ends in the middle of a statement e Acomment was not closed Fatal String exceeds line There is a missing closing in a string so it occupies multiple lines Fatal illegal character argl1 arg2 An illegal character was encountered in the input file Fatal Syntax error argl expected but arg2 found This indicates that the compiler expected a different token than the one you typed It can occur almost anywhere it is possible to make an error against the Pascal language 127 APPENDIX C COMPILER MESSAGES Start reading includefile arg1 When you provide the vt switch the compiler tells you when it starts reading an included file Warning Comment level arg1 found When the vw switch is used then the compiler warns you 1f it finds nested comments Nested comments are not allowed in Turbo Pascal and Delphi and can be a possible source of errors Note Ignored compiler switch arg1 With vn on the compiler warns if it ignores a switch Warning Illegal compiler switch arg1 You included a compiler switch i e which the compiler does not recognise Warning Misplaced global compiler switch The compiler switch is misplaced and should be lo cated at the start of the unit or program Er
103. d for compatibility reasons Error Taking the address of labels defined outside the current scope isn t allowed It isn t allowed to take the address of labels outside the current procedure Error Cannot initialize variables declared as external Variables declared as external can not be initialized with a default value Error Illegal function result type Some types like file types can not be used as function result Error No common type possible between arg1 and arg2 To perform an operation on inte gers the compiler converts both operands to their common type which appears to be an invalid type To determine the common type of the operands the compiler takes the minimum of the minimal values of both types and the maximum of the maximal values of both types The common type is then minimum maximum Error Generics without specialization can not be used as a type for a variable Generics must be always specialized before being used as variable type Warning Register list is ignored for pure assembler routines When using pure assembler rou tines the list with modified registers is ignored Error Variables cannot be exported with a different name on this target add the name to the declaration using the e3 On most targets it is not possible to change the name under which a variable is exported inside the exports statement of a library In that case you have to specify the export name at the point where the variable is declare
104. d to use ON or OFF or a or to toggle the switch Error Resource files are not supported for this target The target you are compiling for doesn t support resource files Warning Include environment arg1 not found in environment The included environment vari able can t be found in the environment it will be replaced by an empty string instead Error Illegal value for FPU register limit Valid values for this directive are 0 8 and NORMAL DE FAULT Warning Only one resource file is supported for this target The target you are compiling for sup ports only one resource file The first resource file found is used the others are discarded Warning Macro support has been turned off A macro declaration has been found but macro support is currently off so the declaration will be ignored To turn macro support on com pile with Sm on the command line or add S MACRO ON in the source Error Illegal interface type specified Valids are COM CORBA or DEFAULT The interface type that was specified is not supported Warning APPID is only supported for PalmOS The APPID directive is only supported for the PalmOS target Warning APPNAME is only supported for PalmOS The SAPPNAME directive is only sup ported for the PalmOS target Error Constant strings can t be longer than 255 chars A single string constant can contain at most 255 chars Try splitting up the string into multiple smaller parts and concatenate them with
105. de Error Set type expected The variable or expression is not of type set This happens in an in statement Warning Function result does not seem to be set You can get this warning if the compiler thinks that a function return value is not set This will not be displayed for assembler procedures or procedures that contain assembler blocks Warning Type arg1 is not aligned correctly in current record for C Arrays with sizes not mul tiples of 4 will be wrongly aligned for C structures Error Unknown record field identifier arg1 The field doesn t exist in the record object defini tion Warning Local variable arg1 does not seem to be initialized This message is displayed if the compiler thinks that a variable will be used i e it appears in the right hand side of an expres sion when it was not initialized first i e appeared in the left hand side of an assigment Warning Variable argl does not seem to be initialized This message is displayed if the com piler thinks that a variable will be used i e it appears in the right hand side of an expression when it was not initialized first i e appeared in the left hand side of an assigment Error identifier idents no member arg1 This error is generated when an identifier of a record field or method is accessed while it is not defined Hint Found declaration argl You get this when you use the vh switch In the case of an over loaded procedure not being found Th
106. depend on the terminal emulation Open Presents a dialog in which a file containing editor preferences can be selected After the dialog 1s closed the preferences file will be read and the preferences will be applied Save Saves the current options in the default file Save as Saves the current options in an alternate file A file selection dialog box will be presented in which the alternate settings file can be specified Please note that options are not saved automatically They should be saved explicitly with the OptionsiSave command 6 4 10 The Window menu The Window menu provides access to some window functions More information on all these functions can be found in section 6 3 page 38 Tile Tiles all opened windows on the desktop Cascade Cascades all opened windows on the desktop Close all Closes all opened windows Size move CTRL F5 Puts the IDE in Size move mode after this command the active window can be moved and resized using the arrow keys Zoom F5 Zooms or unzooms the current window Next F6 Activates the next window in the window list Previous SHIFT F6 Activates the previous window in the window list Hide CTRL F6 Hides the active window Close ALT F3 Closes the active window List ALT 0 Shows the list of opened windows From there a window can be activated closed shown and hidden Refresh display Redraws the screen 46 CHAPTER 6 THE IDE 6 4 11 The Help menu The Help men
107. e Hint Conversion between ordinals and pointers is not portable If you typecast a pointer to a longint or vice versa this code will not compile on a machine using 64 bits addressing Warning Conversion between ordinals and pointers is not portable If you typecast a pointer to an ordinal type of a different size or vice versa this can cause problems This is a warning to help in finding the 32 bit specific code where cardinal longint is used to typecast pointers to ordinals A solution is to use the ptrint ptruint types instead Error Can t determine which overloaded function to call You re calling overloaded functions with a parameter that doesn t correspond to any of the declared function parameter lists e g when you have declared a function with parameters word and longint and then you call it with a parameter which is of type integer Error Illegal counter variable The type of a for loop variable must be an ordinal type Loop variables cannot be reals or strings Warning Converting constant real value to double for C variable argument add explicit typecast to prevent this In C constant real values are double by default For this reason if you pass a constant real value to a variable argument part of a C function FPC by default converts this constant to double as well If you want to prevent this from happening add an explicit typecast around the constant Error Class or COM interface type expected but got arg1 Some
108. e command line will be passed to the program based on the en tries made in the dialog The text typed here will be passed on after replacing some control placeholders with their values A control placeholder is the name of some control in the dialog enclosed in percent char acters The name of the control will be replaced with the text associated with the control Consider the following example e A IA E cc CommandLine n 1 v i Sw Ssearchstr S filemask Here the values associated with the controls named 1 v i w and searchstr and filemask will be inserted in the command line string Default The name of the control that is the default control i e the control that is to have the focus when the dialog is opened The following is an example of a valid main section Main Title GNU Grep Size 56 9 CommandLine n 1 Sv i Sws Ssearchstr S Sfilemask Default searchstr After the Main section a section must be specified for each control that should appear on the dialog Each section has the name of the control it describes as in the following example 65 CHAPTER 6 THE IDE CaseSensitive Type CheckBox Name C ase sensitive Origin 2 6 Size 25 1 Default On On i Each control section must have at least the following keywords associated with it Type The type of control Possible values are Label A plain text label which will be shown on the dialog A control can be linked
109. e highlighted breakpoint can be changed Delete Deletes the highlighted breakpoint The dialog can be closed with the Close button The breakpoint properties dialog is shown in figure 6 12 Figure 6 12 The breakpoint properties dialog c temp hello pas ine ES Conditions rn count The following properties can be set Type Set the type of the breakpoint The following types of breakpoints exist 56 CHAPTER 6 THE IDE function Function breakpoint The program will stop when the function with the given name is reached file line Source line breakpoint The program will stop when the source file with given name and line is reached watch Expression breakpoint An expression may be entered and the program will stop as soon as the expression changes awatch access watch Expression breakpoint An expression that references a memory loca tion may be entered and the program will stop as soon as the memory indicated by the expression is accessed Address stop as soon as an address is reached rwatch read watch Expression breakpoint An expression that references a memory loca tion may be entered and the program will stop as soon as the memory indicated by the expression is read Name Name of the function or file where to stop Conditions Here an expression can be entered which must evaluate to True for the program to stop at the breakpoint The expressions that can be entered must be valid GD
110. e inheritance list Error Type argl can t be used as array index type Types like qword or int 64 aren t allowed as array index type Error Con and destructors aren t allowed in interfaces Constructor and destructor declarations aren t allowed in interfaces In the most cases method QueryInterface of Unknown can be used to create a new interface 141 APPENDIX C COMPILER MESSAGES Error Access specifiers can t be used in INTERFACES The access specifiers public private protected and published can t be used in interfaces because all methods of an interface must be public Error An interface can t contain fields Declarations of fields aren t allowed in interfaces An in terface can contain only methods and properties with method read write specifiers Error Can t declare local procedure as EXTERNAL Declaring local procedures as external is not possible Local procedures get hidden parameters that will make the chance of errors very high Warning Some fields coming before argl weren t initialized In Delphi mode not all fields of a typed constant record have to be initialized but the compiler warns you when it detects such situations Error Some fields coming before argl1 weren t initialized In all syntax modes but Delphi mode you can t leave some fields uninitialized in the middle of a typed constant record Warning Some fields coming after arg1 weren t initialized You can leave some fields at t
111. e pressed simultaneously with the highlighted letter For a button the action associated with the button will then be executed Inside edit fields list boxes and memos navigation is carried out with the usual arrow key commands 6 3 Windows Nowadays working with windowed applications should be no problem for most WINDOWS and LINUX users Nevertheless the following section describes how the windows work in order to derive the most benefit from the Free Pascal IDE 6 3 1 Window basics A common IDE window is displayed in figure 6 2 Figure 6 2 A common IDE window nonameOl1 pas The window is surrounded by a so called frame the white double line around the window At the top of the window 4 things are displayed 38 CHAPTER 6 THE IDE e At the upper left corner of the window a close icon is shown When clicked the window will be closed It can also be closed by pressing ALT F3 or by selecting the menu item Win dowlClose All open windows can be closed by selecting the menu item WindowlClose all In the middle the title of the window is displayed Almost at the upper right corner a number is visible This number identifies the editor window and pressing ALT NUMBER will jump to this window Only the first 9 windows will get such a number At the upper right corner a small green arrow is visible Clicking this arrow zooms the window so it covers the whole desktop Clicking this arrow on a zoomed wi
112. e program exits it outputs a summary of the used memory and dumps a summary of unreleased memory blocks if any keyboard provides basic keyboard handling routines in a platform independent way and supports writing custom drivers macpas This unit implements several functions available only in MACPAS mode This unit should not be included it s automatically included when the MACPAS mode is used 111 CHAPTER 9 UNITS THAT COME WITH FREE PASCAL math This unit contains common mathematical routines trigonometric functions logarithms etc as well as more complex ones summations of arrays normalization functions etc matrix A unit providing matrix manipulation routines mmx This unit provides support for mmx extensions in your code mouse Provides basic mouse handling routines in a platform independent way and supports writing custom drivers objects This unit provides the base object for standard Turbo Pascal objects It also implements File and Memory stream objects as well as sorted and non sorted collections and string streams objpas Is used for Delphi compatibility You should never load this unit explicitly it is automatically loaded if you request Delphi mode printer This unit provides all you need for rudimentary access to the printer using standard I O routines sockets This gives the programmer access to sockets and TCP IP programming strings This unit provides basic string handling routines for the pc
113. e self parameters Error Methods can be only in other methods called direct with type identifier of the class A con struction like somet ype somemethod is only allowed in a method Error Illegal use of You are using the format colon 2 times on an expression that is not a real expression Error range check error in set constructor or duplicate set element The declaration of a set con tains an error Either one of the elements is outside the range of the set type or two of the elements are in fact the same Error Pointer to object expected You specified an illegal type in a new statement The extended syntax of new needs an object as a parameter Error Expression must be constructor call When using the extended syntax of new you must specify the constructor method of the object you are trying to create The procedure you specified is not a constructor Error Expression must be destructor call When using the extended syntax of dispose you must specify the destructor method of the object you are trying to dispose of The procedure you specified is not a destructor Error Illegal order of record elements When declaring a constant record you specified the fields in the wrong order Error Expression type must be class or record type A with statement needs an argument that is of the type record or class You are using with on an expression that is not of this type Error Procedures can t return a value In Free Pas
114. e source file resides 3 It will look in the directory where the compiler binary is 4 It will look in all the directories specified in the unit search path You can add a directory to the unit search path with the Fu see page 5 1 3 option Every occur rence of one of these options will insert a directory to the unit search path i e the last path on the command line will be searched first The compiler adds several paths to the unit search path 1 The contents of the environment variable XXUNITS where XX must be replaced with one of the supported targets GO32V2 LINUX WIN32 0852 BEOS FREEBSD NETBSD The standard unit directory This directory is determined from the FPCDIR environment vari able If this variable is not set then it is defaulted to the following e On LINUX usr local lib fpc FPCVERSION Qr usr lib fpc FPCVERSION whichever is found first e On other OSes the compiler binary directory with appended to it if it exists For instance on Windows this would mean C FPC 2 2 units i386 win32 This is assuming the compiler was installed in the directory C FPC 2 2 After this directory is determined the following paths are added to the search path a FPCDIR units FPCTARGET b FPCDIR units FPCTARGET rtl Here target must be replaced by the name of the target you are compiling for this is a combi nation of CPU and OS so for instance usr local 1ib fp
115. e symbol symbol before processing is started h Emit a small helptext I Include include files instead of dropping the include statement ooutfile If this option is given the output will be written to a file named outfile Note that only one output file can be given 8 6 ppudump program ppudump is a program which shows the contents of a Free Pascal unit It is distributed with the compiler You can just issue the following command ppudump options foo ppu to display the contents of the foo ppu unit You can specify multiple files on the command line The options can be used to change the verbosity of the display By default all available information is displayed You can set the verbosity level using the Vxxx option Here xxx is a combination of the following letters h Show header info i Show interface information 103 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL m Show implementation information d Show only interface definitions s Show only interface symbols b Show browser info a Show everything default if no V option is present 8 7 ppumove program ppumove is a program to make shared or static libraries from multiple units It can be compared with the tpumove program that comes with Turbo Pascal It is distributed in binary form along with the compiler Its usage is very simple ppumove options unitl ppu unit2 ppu unitn ppu where options is a combination of b Generate
116. eS eS 48 S25 Syntax highhewting ooo oscense BS el eS eS 49 636 Code Completion es e666 4 54 ee Reha ewe ee eee ee 49 OSF Code Temples ps eae adoa es ee ee ee ee Pa a 50 66 Searching and replacido s corc ose oh Peete Sse eee os 51 67 The symbol bras io coca a a a a e 53 G8 Running programs co s ie ca ed ee ee SES Sel dees oe 2 54 6 9 Debugeing proprams coco A A ee 55 69 1 Using beeakpomts 5455 45 hh see ee ages eee a eS eS 55 639 2 Using wathes cra se ee ee ee e Eee eo os Eee ee eS 57 A o E A ea a RA REE ER RS Beem i 58 694 The GDB window ooo entro ee EEE SS eww eee e 58 610 Usine Tile co e Se Ee ea ee Re ele wa ee ale a 59 6 10 1 The messages window 2 6 ee ee ee ee 59 GIOT AMER cia oa oe ee SE Aas eee eee E 60 0103 The ASCHD kk moe he GR ee RE a la 60 6 100 The Calcula ds doe ee ee ee Gaal eed a 61 GUS Aces new LORIE oe cra as E ee Ee A e 62 610 6 Meta parameters sc ero ke ea a Ee PAN eed be 63 6 10 7 Building a command line dialog box 00 65 6 11 Project management and compiler options 200 67 CONTENTS 6111 The pimay tle se ic A kee PAAR id 67 0 112 Thedirectory melee ne sce A A ee a FS 68 O 11 3 The target operating SYSTEM lt lt a ke e 68 011A Compiler ophons 62 2s 4 kee eo e ee ee Oe a 69 UL LMK opionS lt cee camina ah eae Se AE oe ee Ee re Hs 74 6116 Memory sE ka ee oA eee bis See eee bie es 75 GIL Debug Opens sos E A de eS 76 611 8 The swiichies Mode
117. ecify a mode the mode specified on the command line is used If the source file specifies a mode then it overrides the mode given on the command line 89 CHAPTER 7 PORTING AND PORTABLE CODE Thus compiling a unit with the M switch as follows fpc MOBJFPC myunit 1s the same as having the following mode directive in the unit SMODE OBJFPC Unit myunit The MODE directive should always be located before the uses clause of the unit interface or program uses clause because setting the mode may result in the loading of an additional unit as the first unit to be loaded Note that the SMODE directive is a global directive i e it is valid for the whole unit Only one directive can be specified The mode has no influence on the availability of units all available units can be used independent of the mode that is used to compile the current unit or program 7 2 Turbo Pascal Free Pascal was originally designed to resemble Turbo Pascal as closely as possible There are of course restrictions Some of these are due to the fact that Turbo Pascal was developed for 16 bit architectures whereas Free Pascal is a 32 bit 64 bit compiler Other restrictions result from the fact that Free Pascal works on more than one operating system In general we can say that if you keep your program code close to ANSI Pascal you will have no problems porting from Turbo Pascal or even Delphi to Free Pascal To a large extent the constructs
118. eclaration that contains a dot i e an object or class method but the procedure name is not a procedure of this type Error function header doesn t match any method of this class arg1 This identifier is not a method This happens when the compiler scans a procedure declaration that contains a dot i e an ob ject or class method but the procedure name is not a procedure of this type procedure function arg1 When using the vd switch the compiler tells you when it starts process ing a procedure or function implementation Error Illegal floating point constant The compiler expects a floating point expression and gets something else Error FAIL can be used in constructors only You are using the fail keyword outside a con structor method Error Destructors can t have parameters You are declaring a destructor with a parameter list Destructor methods cannot have parameters Error Only class methods can be referred with class references This error occurs in a situation like the following Type Tclass Class of Tobject Var TClass begin C free Free is not a class method and hence cannot be called with a class reference Error Only class methods can be accessed in class methods This is related to the previous error You cannot call a method of an object from inside a class method The following code would produce this error 134 APPENDIX C COMPILER MESSAGES class procedure tobject x begin free
119. ectly Remember that the compiler looks for units only in the current directory and in the directory where the compiler itself is If you want it to look somewhere else too you must explicitly tell it to do so using the Fu see page 5 1 3 option Or you must set up a configuration file Problems you may encounter under DOS No space in environment An error message like this can occur if you call SET_PP BAT in AUTOEXEC BAT To solve this problem you must extend your environment memory To do this search a line in CONFIG SYS like SHELL C DOS COMMAND COM and change it to the following SHELL C ADOSXCOMMAND COM E 1024 You may just need to specify a higher value if this parameter is already set Coprocessor missing If the compiler writes a message that there is no coprocessor install the coprocessor emulation Not enough DPMI memory If you want to use the compiler with DPMI you must have at least 7 8 MB free DPMI memory but 16 Mb is a more realistic amount 22 Chapter 5 Compiler configuration The output of the compiler can be controlled in many ways This can be done essentially in two distinct ways e Using command line options e Using the configuration file fpc cfg The compiler first reads the configuration file Only then are the command line options checked This creates the possibility to set some basic options in the configuration file and at the same time you can still set some s
120. ed arg1 but got arg2 at arg3 The type check of a compile time expression failed Note APPTYPE is not supported by the target OS The SAPPTYPE directive is supported by certain operating systems only Error Illegal optimization specified arg1 You specified an optimization with the SOPTIMIZATION xxx directive and the compiler didn t recognize the optimization you specified Warning SETPEFLAGS is not supported by the target OS The SSETPEFLAGS directive is not supported by the target OS Warning IMAGEBASE is not supported by the target OS The IMAGEBASE directive is not supported by the target OS Warning MINSTACKSIZE is not supported by the target OS The SMINSTACKSIZE direc tive is not supported by the target OS Warning MAXSTACKSIZE is not supported by the target OS The SMAXSTACKSIZE direc tive is not supported by the target OS Error Illegal state for WARN directive Only ON and OFF can be used as state with a SWARN compiler directive Error Illegal set packing value Only 0 1 2 4 8 DEFAULT and NORMAL are allowed as pack set parameters Warning PIC directive or switch ignored Several targets such as WINDOWS do not support nor need PIC so the PIC directive and switch are ignored Warning The switch arg1 is not supported by the currently selected target Some compiler switches like E are not supported by all targets Warning Framework related options are onl
121. ed in the command line if it is referenced there The following keyword can be specified in a inputline control section Value A standard value text for the edit control can be specified This value will be filled in when the dialog appears The following is an example of an input line section 66 CHAPTER 6 THE IDE filemask Type InputLine Origin 2 4 Size 22 1 Value pas pp inc A checkbox control Type CheckBox presents a checkbox which can be in one of two states on or of f With each of these states a value can be associated which will be passed on to the command line The following keywords can appear in a checkbox type section Name The text that appears after the checkbox If there is a highlighted letter in it this letter can be used to set or unset the checkbox using the ALT letter combination Default Specifies whether the checkbox is checked or not when the dialog appears value on or off On The text associated with this checkbox if it is in the checked state Off The text associated with this checkbox if it is in the unchecked state The following is an example of a valid checkbox description 1 Type CheckBox Name C ase sensitive Origin 2 6 Size 25 1 Default On On i If the checkbox is checked then the value i will be added on the command line of the tool If it is unchecked no value will be added 6 11 Project management and compiler options Project managemen
122. eed to the compiler FPCFULLVERSION is replaced by the compiler s version string FPCVERSION is replaced by the compiler s version string FPCDATE is replaced by the compiler s date FPCTARGET is replaced by the compiler s target combination of CPU OS FPCCPU is replaced by the compiler s target CPU FPCOS is replaced by the compiler s target OS To have these variables subsituted just insert them with a prepended as follows Fu usr lib fpc SFPCVERSION rt1 SFPCOS This is equivalent to Fu usr lib fpc 2 2 2 rt1 linux if the compiler version is 2 2 2 and the target OS is LINUX These replacements are valid on the command line and also in the configuration file On the linux command line you must be careful to escape the since otherwise the shell will attempt to expand the variable for you which may have undesired effects 34 Remark Chapter 6 The IDE The IDE Integrated Development Environment provides a comfortable user interface to the com piler It contains an editor with syntax highlighting a debugger symbol browser etc The IDE is a text mode application which has the same look and feel on all supported operating systems It is modelled after the IDE of Turbo Pascal so many people should feel comfortable using it Currently the IDE is available for DOS WINDOWS and LINUX 6 1 First steps with the IDE 6 1 1 Starting the IDE The IDE is started by entering the command fp at the com
123. efined You are defining a label twice You can define a label only once Error illegal type declaration of set elements The declaration of a set contains an invalid type definition Error Forward class definition not resolved arg1 You declared a class but you did not imple ment it Hint Unit arg1 not used in arg2 The unit referenced in the uses clause is not used Hint Parameter arg1 not used The identifier was declared locally or globally but was not used locally or globally Note Local variable arg1 not used You have declared but not used a variable in a procedure or function implementation Hint Value parameter arg1 is assigned but never used The identifier was declared locally or globally and assigned to but is not used locally or globally after the assignment 152 APPENDIX C COMPILER MESSAGES Note Local variable argl is assigned but never used The variable in a procedure or function implementation is declared and assigned to but is not used after the assignment Hint Local arg1 arg2 is not used A local symbol is never used Note Private field argl arg2 is never used The indicated private field is defined but is never used in the code Note Private field arg1 arg2 is assigned but never used The indicated private field is declared and assigned to but never read Note Private method arg1 arg2 never used The indicated private method is declared but is never used in the co
124. egment 16 bit addressing is not supported You must use 32 bit addressing Constant reference not allowed It is not allowed to try to address a constant memory address in protected mode Segment overrides not supported Intel style eg rep ds stosb segment overrides are not supported by the assembler parser Expressions of the form sreg reg are currently not supported To access a memory operand in a different segment you should use the sreg reg snytax instead of sreg reg Size suffix and destination register do not match In intel AT amp T syntax you are using a register size which does not concord with the operand size specified Invalid assembler syntax No ref with brackets Trying to use a negative index register Local symbols not allowed as references Invalid operand in bracket expression Invalid symbol name Invalid Reference syntax Invalid string as opcode operand Null label references are not allowed Using a defined name as a local label Invalid constant symbol Invalid constant expression at beginning of line not allowed NOR not supported Invalid floating point register name Invalid floating point constant 166 APPENDIX C COMPILER MESSAGES Asm syntax error Should start with bracket Asm syntax error register Asm syntax error in opcode operand Invalid String expression Constant expression out of bounds Invalid or missing opcode Invalid real constant expression Parenthesis are not
125. en all candidate overloaded procedures are listed with their parameter lists Error Data element too large You get this when you declare a data element whose size exceeds the prescribed limit 2 Gb on 80386 68020 processors Error No matching implementation for interface method arg1 found There was no match ing method found which could implement the interface method Check argument types and result type of the methods Warning Symbol arg1 is deprecated This means that a symbol a variable routine etc which is declared as deprecated is used Deprecated symbols may no longer be available in newer versions of the unit library Use of this symbol should be avoided as much as possible Warning Symbol arg1 is not portable This means that a symbol a variable routine etc which is declared as platform is used This symbol s value use and availability is plat form specific and should not be used if the source code must be portable Warning Symbol arg1 is not implemented This means that a symbol a variable routine etc which is declared as unimplemented is used This symbol is defined but is not yet imple mented on this specific platform 153 APPENDIX C COMPILER MESSAGES Error Can t create unique type from this type Only simple types like ordinal float and string types are supported when redefining a type with type newtype type oldtype Hint Local variable arg1 does not seem to be initi
126. entries can be used to quickly reload these files in the editor 6 4 3 The Edit menu The Edit menu contains entries for accessing the clipboard and undoing or redoing editing ac tions Most of these functions have shortcut keys associated with them Undo ALT BKSP Reverses the effect of the last editing action The editing actions are stored ina buffer Selecting this mechanism will move backwards through this buffer i e multiple undo levels are possible However any selections that may have been made are not reproduced Redo Repeats the last action that was just undone with Undo Redo can redo multiple undone actions Cut SHIFT DEL Deletes the selected text from the window and copies it to the clipboard Any previous clipboard contents are lost The new clipboard contents are available for pasting elsewhere Copy CTRL INS Copies the current selection to the clipboard Any previous clipboard contents are lost The new clipboard contents are available for pasting elsewhere Paste SHIFT INS Inserts the current clipboard contents in the text at the cursor position The clipboard contents remain as they were Clear CTRL DEL Clears i e deletes the current selection Select All Selects all text in the current window The selected text can then be cut or copied to the clipboard Unselect undo the selection Show clipboard Opens a window in which the current clipboard contents are shown When running an IDE under WINDOW
127. erred base address to hhh a hexadecimal address 28 CHAPTER 5 COMPILER CONFIGURATION C Generate a console application or a gui application D Force use of Def file for exports F Generate a FS application or a console application G Generate a GUI application or a console application N Do not generate a relocation section R Generate a relocation section T Generate a TOOL application or a console application Xx Specify executable options This tells the compiler what kind of executable should be generated The parameter x can be one of the following c LINUX only Link with the C library You should only use this when you start to port Free Pascal to another operating system d Do not use the standard library path This is needed for cross compilation to avoid linking with the host platform s libraries D Link with dynamic libraries defines the FPC_LINK_DYNAMIC symbol e use external GNU linker g Create debug information in a separate file and add a debuglink section to executable i use internal linker MXXX Set the name of the program entry routine The default is main m Generate linker map file PXXX Prepend binutils names with XXX for cross compiling rXXX Set library path to XXX Rxxx Prepend xxx to all linker search paths used for cross compiling s Strip the symbols from the executable S Link with static units defines the FPC_LINK_STATIC
128. es units and the SysUtils unit are guaranteed to work on all systems So is the DOS unit but that is deprecated 97 CHAPTER 7 PORTING AND PORTABLE CODE e Avoid direct hardware access Limited console like hardware access is available for most platforms in the Video Mouse and Keyboard units e Do not use hard coded filename conventions See below for more information on this e Make no assumptions on the internal representation of types Various processors store infor mation in different ways endianness If system specific functionality is needed it is best to separate this out in a single unit Porting efforts will then be limited to re implementing this unit for the new platform e Don t use assembler unless you have to Assembler is processor specific Some instructions will not work even on the same processor family e Do not assume that pointers and integers have the same size They do on an Intel 32 bit processor but not necessarily on other processors The Pt rInt type is an alias for the integer type that has the same size as a pointer SizeInt is used for all size related issues The system unit contains some constants which describe file access on a system AllFilesMask a file mask that will return all files in a directory This is x on Unix like platforms and x on dos and windows like platforms LineEnding A character or string which describes the end of line marker used on the current plat form Comm
129. essor cycle after an application asked the OS how much memory is free another application may have allocated everything 2 It is not clear what free memory means does it include swap memory does it include disk cache memory the disk cache can grow and shrink on modern OS es does it include memory allocated to other applications but which can be swapped out etc Therefore programs using MemAvail and MaxAvail functions should be rewritten so they no longer use these functions because it does not make sense any more on modern OS es There are 3 possibilities The DOS extender GO32V2 falls under this definition of modern because it can use paged memory and run in multi tasked environments 94 CHAPTER 7 PORTING AND PORTABLE CODE 1 Use exceptions to catch out of memory errors 2 Set the global variable ReturnNillfGrowHeapFails to True and check after each allocation whether the pointer is different from Nil 3 Don t care and declare a dummy function called MaxAvail which always returns High LongInt or some other constant 7 2 4 A note on long file names under DOS Under WINDOWS 95 and higher long filenames are supported Compiling for the WINDOWS target ensures that long filenames are supported in all functions that do file or disk access in any way Moreover Free Pascal supports the use of long filenames in the system unit and the Dos unit also for go32v2 executables The system unit contains the boo
130. fpc S Support operators like C x and Sa Turn on assertions Sd Same as Mdelphi Se lt x gt Error options lt x gt is a combination of the following lt n gt Compiler halts after the lt n gt errors default is 1 w Compiler also halts after warnings n Compiler also halts after notes h Compiler also halts after hints S9 Enable LABEL and GOTO default in Mtp and Mdelphi Sh Use ansistrings by default instead of shortstrings Si Turn on inlining of procedures functions declared as inline Sk Load fpcylix unit SI lt x gt Set interface style to lt x gt SIcom COM compatible interface default SIcorba CORBA compatible interface Sm Support macros like C global S0 Same as Mtp Ss Constructor name must be init destructor must be done St Allow static keyword in objects 5X Enable exception keywords default in Delphi ObjFPC modes sS Do not call assembler and linker sh Generate script to link on host st Generate script to link on target sr Skip register allocation phase use with alr T lt x gt Target operating system Tlinux Linux u lt x gt Undefines the symbol lt x gt U Unit options Un Do not check where the unit name matches the file nam Ur Generate release unit files never automatically recompiled Us Compile a system unit v lt x gt Be verbose lt x gt is a combination of the following letters
131. gle double ansistring widestring tdatetime variant olevariant wordbool and all interfaces are automatable Hint Converting the operands to arg1 before doing the add could prevent overflow errors Adding two types can cause overflow errors Since you are converting the result to a larger type you could prevent such errors by converting the operands to this type before doing the addition Hint Converting the operands to arg1 before doing the subtract could prevent overflow errors Subtracting two types can cause overflow errors Since you are converting the result to a larger type you could prevent such errors by converting the operands to this type before doing the subtraction Hint Converting the operands to arg1 before doing the multiply could prevent overflow errors Multiplying two types can cause overflow errors Since you are converting the result to a larger type you could prevent such errors by converting the operands to this type before doing the multiplication Warning Converting pointers to signed integers may result in wrong comparison results and range errors use an unsi The virtual address space on 32 bit machines runs from 00000000 to ffffffff Many operat ing systems allow you to allocate memory above 80000000 For example both WINDOWS and LINUX allow pointers in the range 0000000 to bfffffff If you convert pointers to signed types this can cause overflow and range check errors but also 80000000
132. gs under a common name It provides 3 names under which the switches can be saved Normal For normal fast compilation Debug For debugging intended to set most debug switches on Also useful for setting conditional defines that e g allow including some debug code Release For a compile of the program as it should be released debug information should be off the binary should be stripped and optimizations should be used Selecting one of these modes will load the compiler options as they were saved the last time the selected mode was active i e it doesn t specifically set or unset options When setting and saving compiler options be sure to select the correct switch mode first it makes little sense to set debug options while the release switch is active The switches mode dialog is shown in figure 6 32 6 12 Customizing the IDE The IDE is configurable over a wide range of parameters colors can be changed screen resolution The configuration settings can be reached via the sub menu Environment in the Options menu 77 CHAPTER 6 THE IDE Figure 6 32 The switches mode dialog Normal Figure 6 33 The preferences dialog I 80x25 color Y Desktop file lt gt C rrent directory gt Conf g file directory uto save Editor iles X nvironment Kk esktop Options uto track source X C ose on go to source X C ange dir on open 6 12 1 Preferences The preferences di
133. h allows the setting of a bookmark at the current cursor position Later the cursor can be returned to this position by pressing a keyboard shortcut Up to 9 bookmarks per source file can be set up they are set by CTRL K lt NUMBER gt where number 1s the number of the bookmark To go to a previously set bookmark press CTRL Q lt NUMBER gt Currently the bookmarks are not saved when the IDE is exited This may change in future imple mentations of the IDE 6 5 4 Jumping to a source line It is possible to go directly to a specific source line To do this open the goto line dialog via the SearchiGoto line number menu In the dialog that appears the line number the IDE should jump to can be entered The goto line dialog is shown in figure 6 4 Figure 6 4 The goto line dialog n 48 CHAPTER 6 THE IDE 6 5 5 Syntax highlighting The IDE is capable of syntax highlighting i e the color of certain Pascal elements can be set As text is entered in an editor window the IDE will try to recognise the elements and set the color of the text accordingly The syntax highlighting can be customized in the colors preferences dialog using the menu option Optionsl EnvironmentlColors In the colors dialog the group Syntax must be selected The item list will then display the various syntactical elements that can be colored Whitespace The empty text between words Note that for whitespace only the background color will be u
134. har type comparable to similar routines in standard C libraries system This unit is available for all supported platforms It includes among others basic file I O routines memory management routines all compiler helper routines and directory services routines strutils Offers a lot of extended string handling routines dateutils Offers a lot of extended date time handling routines for almost any date and time math sysutils Is an alternative implementation of the sysutils unit of Delphi It includes file I O access routines which takes care of file locking date and string handling routines file search date and string conversion routines typinfo Provides functions to access runtime Type Information just like Delphi variants Provides basic variant handling video Provides basic screen handling in a platform independent way and supports writing custom drivers 9 2 Under DOS emu387 This unit provides support for the coprocessor emulator go32 This unit provides access to capabilities of the GO32 DOS extender 9 3 Under Windows wincrt This implements a console in a standard GUI window contrary to the crt unit which is for the Windows console only Windows This unit provides access to all Win32 API calls Effort has been taken to make sure that it is compatible to the Delphi version of this unit so code for Delphi is easily ported to Free Pascal 112 CHAPTER 9 UNITS THAT COME WITH FREE PASCAL opengl Provides ac
135. haracter On by default Persistent blocks When a selection is made and the cursor is moved the selection is not destroyed i e the selected block stays selected On by default Syntax highlight Use syntax highlighting on the files that have an extension which appears in the list of highlight extensions On by default Block insert cursor The insert cursor is a block instead of an underscore character By default the overwrite cursor is a block This option reverses that behaviour Off by default Vertical blocks When selecting blocks spanning several lines the selection doesn t contain the en tirety of the lines within the block instead it contains the lines as far as the column on which the cursor is located Off by default Highlight column When checked the current column i e the column where the cursor is is high lighted Off by default Highlight row When checked the current row i e the row where the cursor is is highlighted Off by default Auto closing brackets When an opening bracket character is typed the closing bracket is also in serted at once Off by default Keep trailing spaces When saving a file the spaces at the end of lines are stripped off This option disables that behaviour i e any trailing spaces are also saved to file Off by default Codecomplete enabled Enable code completion On by default Enable folds Enable code folding Off by default Tab size The number of spaces that are inserted w
136. hat you need to do now is give the following command install sh And then you must answer some questions They re very simple they re mainly concerned with 2 things 1 Places where you can install different things 2 Deciding if you want to install certain components such as sources and demo programs The script will automatically detect which components are present and can be installed It will only offer to install what has been found Because of this feature you must keep the original names when downloading since the script expects this If you run the installation script as the root user you can just accept all installation defaults If you don t run as root you must take care to supply the installation program with directory names where you have write permission as it will attempt to create the directories you specify In principle you can install it wherever you want though At the end of installation the installation program will generate a configuration file fpc cfg for the Free Pascal compiler which reflects the settings that you chose It will install this file in the etc directory or in your home directory with name fpc cfg if you do not have write permission in the etc directory It will make a copy in the directory where you installed the libraries The compiler will first look for a file fpc cfg in your home directory before looking in the etc directory 2 3 Optional configuration steps On any
137. he end of a type constant record uninitialized The compiler will initialize them to zero automati cally This may be the cause of subtle problems Error VarArgs directive or in MacPas without CDecl CPPDecl MWPascal and External The varargs directive or the varargs parameter in MacPas mode can only be used with procedures or functions that are declared with external and one of cdecl cppdecl and mwpascal This functionality is only supported to provide a compatible interface to C func tions like printf Error Self must be a normal call by value parameter You can t declare Sel f as a const or var parameter it must always be a call by value parameter Error Interface arg1 has no interface identification When you want to assign an interface to a constant then the interface must have a GUID value set Error Unknown class field or method identifier arg1 Properties must refer to a field or method in the same class Warning Overriding calling convention arg1 with arg2 There are two directives in the pro cedure declaration that specify a calling convention Only the last directive will be used Error Typed constants of the type procedure of object can only be initialized with NIL You can t assign the address of a method to a typed constant which has a procedure of object type because such a constant requires two addresses that of the method which is known at compile time and that of the
138. he keyboard It is used for typing and navigating through the sources e Editing commands such as copying and pasting text e Moving and resizing windows e Itcan be used to access the menu by pressing ALT and the appropriate highlighted menu letter or by pressing F10 and navigating through the menu with the arrow keys More information on the menu can be found in section 6 4 page 40 e Many commands in the IDE are bound to shortcuts i e typing a special combination of keys will execute a command immediately Remark e When working in a LINUX X Term or through a telnet session the key combination with ALT may not be available To remedy this the CTRL Z combination can be typed first This means that e g ALT X can be replaced by CTRL Z X Alternatively you can try the key combination ESC X for ALT X when working on LINUX e A complete reference of all keyboard shortcuts can be found in section 6 14 page 85 6 2 2 Using the mouse If the system is equipped with a mouse it can be used to work with the IDE The left button is used to select menu items press buttons select text blocks etc The right mouse button is used to access the local menu if available Holding down the CTRL or ALT key and clicking the right button will execute user defined functions See section 6 12 4 page 82 Remark 1 Occasionally the manual uses the term drag the mouse This means that the mouse is moved while the left mouse button is being
139. hen the TAB key is pressed The default value is 8 Indent size The number of spaces a block is indented when calling the block indent function The default value is 2 Highlight extensions When syntax highlighting is on the list of file masks entered here will be used to determine which files are highlighted File masks should be separated with semicolon characters The default is pas pp inc File patterns needing tabs Some files such as makefiles need actual tab characters instead of spaces Here a series of file masks can be entered to indicate files for which tab characters will always be used Default is make make Remark These options will not be applied to already opened windows only newly opened windows will have these options 81 CHAPTER 6 THE IDE Figure 6 36 The Keyboard amp mouse options dialog Mouse Options eys for cut copy and paste BM CUA 91 convention Shift Del Ctrl Ins Shift Ins 6 12 4 Keyboard amp Mouse The Keyboard amp mouse options dialog is called by the menu item Options Environment Keyboard amp Mouse It allows adjusting the behaviour of the keyboard and mouse as well as the sensitivity of the mouse The keyboard and mouse options dialog is shown in figure 6 36 Keys for copy cut and paste Set the keys to use for clipboard operations e CUA 91 convention Shift Del Ctrl Ins Shift Ins e Microsoft convention Ctrl X Ctrl C Ctrl V Mouse double click The slider
140. his instruction Invalid combination of override and opcode This opcode cannot be overriden by this combina tion Too many operands on line At most three operand instructions exist on the m68k and 1386 you are probably trying to use an invalid syntax for this opcode Duplicate local symbol You are trying to redefine a local symbol such as a local label Unknown label identifer Undefined local symbol local symbol not found inside asm statement This label does not seem to have been defined in the current scope Assemble node syntax error Not a directive or local symbol The assembler statement is invalid or you are not using a recog nized directive 165 APPENDIX C COMPILER MESSAGES C 11 2 1386 specific errors repeat prefix and a segment override on lt i386 A problem with interrupts and a prefix instruc tion may occur and may cause false results on 386 and earlier computers Fwait can cause emulation problems with emu387 This warning is reported when using the FWAIT instruction It can cause emulation problems on systems which use the em387 dxe emulator You need GNU as version gt 2 81 to compile this MMX code MMX assembler code can only be compiled using GAS v2 8 1 or later NEAR ignored FAR ignored NEAR and FAR are ignored in the Intel assemblers but are still accepted for compati blity with the 16 bit code model Invalid size for MOVSX MOVZX 16 bit base in 32 bit segment 16 bit index in 32 bit s
141. hyperlinks these are sensitive locations that lead to another topic in the help system They are marked by a different color The hyperlinks can be activated in one of two ways 1 by directly clicking the one you want with the mouse or 2 by using the TAB and SHIFT TAB keys to move between the different hyperlinks of a page and then pressing the ENTER key to activate the one you want When SHIFT F1 is pressed the contents of the help system are displayed To go back to the previous help topic press ALT F1 This also works if the help window isn t displayed on the desktop the help window will then be activated 6 13 2 Working with help files The IDE contains a help system which can display the following file formats TPH The help format for the Turbo Pascal help viewer INF The OS 2 help format NG The Norton Guide Help format HTML HTML files In future some more formats may be added However the above formats should cover already a wide spectrum of available help files Remark Concerning the support for HTML files the following should be noted 1 The HTML viewer of the help system is limited it can only handle the most basic HTML files graphics excluded since it is only designed to display the Free Pascal help files 6 but feel free to improve it and send patches to the Free Pascal development team 83 CHAPTER 6 THE IDE 2 When the HTML help viewer encounters a graphics file it will try and find
142. ical order the currently defined keywords that are available for comple tion The following buttons are available Ok Saves all changes and closes the dialog Edit Pops up a dialog that allows the editing of the currently highlighted keyword New Pops up a dialog that allows the entry of a new keyword which will be added to the list Delete Deletes the currently highlighted keyword from the list Cancel Discards all changes and closes the dialog All keywords are saved and are available the next time the IDE is started Duplicate names are not allowed If an attempt is made to add a duplicate name to the list an error will follow 49 CHAPTER 6 THE IDE A AL A K array 6 5 7 Code Templates Code templates are a way to insert large pieces of code at once Each code templates is identified by a unique name This name can be used to insert the associated piece of code in the text For example the name ifthen could be associated to the following piece of code If Then begin end A code template can be inserted by typing its name and pressing CTRL J when the cursor is posi tioned right after the template name If there is no template name before the cursor a dialog will pop up to allow selection of a template If a vertical bar l is present in the code template the cursor is positioned on it and the vertical bar is deleted In the above example the cursor would be positioned between the if and then ready
143. ich only features supported by the original compiler are supported Currently 5 modes are supported FPC This is the original Free Pascal compiler mode here all language constructs except classes interfaces and exceptions are supported Objects are supported in this mode This is the default mode of the compiler OBJFPC This is the same mode as FPC mode but it also includes classes interfaces and exceptions TP Turbo Pascal compatibility mode In this mode the compiler tries to mimic the Turbo Pascal compiler as closely as possible Obviously only 32 bit or 64 bit code can be compiled DELPHI Delphi compatibility mode In this mode the compiler tries to resemble the Delphi com piler as best as it can All Delphi 7 features are implemented Features that were implemented in the NET versions of Delphi are not implemented MACPAS the Mac Pascal compatibility mode In this mode the compiler attempts to allow all con structs that are implemented in Mac pascal In particular it attempts to compile the universal interfaces The compiler mode can be set on a per unit basis each unit can have its own compiler mode and it is possible to use units which have been compiled in different modes intertwined The mode can be set in one of 2 ways 1 On the command line with the M switch 2 In the source file with the SMODE directive Both ways take the name of the mode as an argument If the unit or program source file does not sp
144. ies on LINUX or other Unices Chxxx Reserves xxx bytes heap xxx should be between 1024 and 67107840 Ci Generate Input Output checking code In case some input output code of your program returns an error status the program will exit with a run time error Which error is generated depends on the I O error Cn Omit the linking stage Co Generate Integer overflow checking code In case of integer errors a run time error will be generated by your program CO Check for possible overflow of integer operations CpXXX Set the processor type to XXX CPX N Set the packing for X to N X can be PACKSET PACKENUM or PACKRECORD and N can be a value of 1 2 4 8 or one of the keywords DEFAULT or NORMAL Cr Generate Range checking code If your program accesses an array element with an invalid index or if it increases an enumerated type beyond its scope a run time error will be generated CR Generate checks when calling methods to verify if the virtual method table for that object is valid Csxxx Set stack size to xxx Ct Generate stack checking code If your program performs a faulty stack operation a run rime error will be generated 26 CHAPTER 5 COMPILER CONFIGURATION CX Create a smartlinked unit when writing a unit Smartlinking will only link in the code parts that are actually needed by the program All unused code is left out This can lead to substantially smaller binaries dxxx
145. ikely that the runtime library you re using doesn t match the compiler in use If you changed the runtime library this error means that you removed a subroutine which the compiler needs for internal use Fatal Cannot find system type arg1 Check if you use the correct run time library The com piler expects that the runtime library contains certain type definitions If you see this error and you didn t change the runtime library code it s very likely that the runtime library you re using doesn t match the compiler in use If you changed the runtime library this error means that you removed a type which the compiler needs for internal use Hint Inherited call to abstract method ignored This message appears only in Delphi mode when you call an abstract method of a parent class via inherited The call is then ignored Error Goto label arg1 not defined or optimized away The label used in the goto definition is not defined or optimized away by the unreachable code elemination C 7 Errors of assembling linking stage This section lists errors that occur when the compiler is processing the command line or handling the configuration files Warning Source operating system redefined The source operating system is redefined Info Assembling pipe argl Assembling using a pipe to an external assembler Error Can t create assembler file arg1 The mentioned file can t be created Check if you have access permissions to create this
146. ile menu The Compile menu contains all entries related to compiling a program or unit Compile ALT F9 Compiles the contents of the active window irrespective of the primary file setting Make F9 Compiles the contents of the active window and any files that the unit or program de pends on and that were modified since the last compile If the primary file was set the primary file is compiled instead Build Compiles the contents of the active window and any files that the unit or program depends on whether they were modified or not If the primary file was set the primary file is compiled instead Target Sets the target operating system for which the program should be compiled Primary file Sets the primary file If set any run or compile command will act on the primary file instead of on the active window The primary file need not be loaded in the IDE for this to have effect Clear primary file Clears the primary file After this command any run or compile action will act on the active window Compiler messages F12 Displays the compiler messages window This window will display the messages generated by the compiler during the most recent compile 6 4 7 The Debug menu The Debug menu contains menu entries to aid in debugging a program such as setting breakpoints and watches Output Show user program output in a window User screen ALT F5 Switches to the screen as it was last left by the running program Add w
147. in enumerate item Search for the original file name i e preserves cas item Search for the filename all lowercased item Search for the filename all uppercased end enumerate This is necessary since Pascal is case independent and the statements var Uses Unitl or var uses unitl should have the sam ffect It will do this first with the extension file ppu the compiled unit file pp and then with the extension file pas For instance suppose that the file file foo pp needs the unit file bar Then the command begin verbatim fpc Fu Fuunits foo pp will tell the compiler to look for the unit bar in the following places 1 In the current directory 2 In the directory where the compiler binary is not under LINUX 3 In the parent directory of the current directory S In the subdirectory units of the current directory Nn In the standard unit directory 18 CHAPTER 3 COMPILER USAGE Also unit names that are longer than 8 characters will first be looked for with their full length If the unit is not found with this name the name will be truncated to 8 characters and the compiler will look again in the same directories but with the truncated name If the compiler finds the unit it needs it will look for the source file of this unit in the same directory where it found the unit If 1t finds the source of the unit then it will compare the file times If the
148. ing to assign an overloaded function to a procedural variable This is not allowed Error string length must be a value from 1 to 255 The length of a shortstring in Pascal is limited to 255 characters You are trying to declare a string with length less than 1 or greater than 255 133 APPENDIX C COMPILER MESSAGES Warning use extended syntax of NEW and DISPOSE for instances of objects If you have a pointer a to an object type then the statement new a will not initialize the object i e the con structor isn t called although space will be allocated You should issue the new a init statement This will allocate space and call the constructor of the object Warning use of NEW or DISPOSE for untyped pointers is meaningless Error use of NEW or DISPOSE is not possible for untyped pointers You cannot use new p or dispose p if p is an untyped pointer because no size is associated to an untyped pointer It is accepted for compatibility in TP and DELPHI modes but the compiler will still warn you if it finds such a construct Error class identifier expected This happens when the compiler scans a procedure declaration that contains a dot i e an object or class method but the type in front of the dot is not a known type Error type identifier not allowed here You cannot use a type inside an expression Error method identifier expected This identifier is not a method This happens when the com piler scans a procedure d
149. ion Note that the location itself is not included in the list See section 3 1 2 page 16 for more information about this option FUxxx Write units to directory xxx instead of the current directory It overrides the FE option Ixxx Add xxx to the include file search path This option has the same effect as Fi 5 1 4 Options controlling the kind of output For more information on these options see Programmers guide a Do not delete the assembler files not applicable when using the internal assembler This also applies to the possibly generated batch script al Include the source code lines in the assembler file as comments an Write node information in the assember file nodes are the way the compiler represents state ments or parts thereof internally This is primarily intended for debugging the code generated by the compiler ap Use pipes instead of creating temporary assembler files This may speed up the compiler on os 2 and LINUX Only with assemblers such as GNU if the internal assembler is used ar List register allocation and release info in the assembler file This is primarily intended for debugging the code generated by the compiler at List information about temporary allocations and deallocations in the assembler file Axxx specify what kind of assembler should be generated Here xxx is one of the following default Use the built in default as Assemble using GNU as nasmcoff Coff Go32v2 file u
150. ion message L file SLINK Link object file SLIBRARYPATH F1 Set library path SLINKLIB name Link library SM MIN MAX SMEMORY Set memory sizes SMACRO Sm Allow use of macros SMESSAGE Emit message SMODE Set compatibility mode SNOTE Emit note message SOBJECTPATH Fo Set object path SOUTPUT A Set output format SPACKENUM Enumeration type size SPACKRECORDS Record element alignment SSATURATION Saturation ignored SSTOP Stop compilation SUNDEF Undefine symbol 174
151. ion steps The LINUX distribution of Free Pascal comes in three forms e atar gz version also available as separate files e a rpm Red Hat Package Manager version and e a deb Debian version Tf you use the rpm format installation is limited to rpm i fpc X Y Z N ARCH rpm Where X Y Z is the version number of the rpm file and ARCH is one of the supported architectures 1386 x86_64 etc If you use Debian installation is limited to dpkg i fpc XXX deb Here again XXX is the version number of the deb file 13 CHAPTER 2 INSTALLING THE COMPILER You need root access to install these packages The tar file allows you to do an installation below your home directory if you don t have root permissions When downloading the t ar file or the separate files installation is more interactive In case you downloaded the tar file you should first untar the file in some directory where you have write permission using the following command tar xvf fpc tar We supposed here that you downloaded the file fpc tar somewhere from the Internet The real filename will have some version number in it which we omit here for clarity When the file is untarred you will be left with more archive files and an install program an instal lation shell script If you downloaded the files as separate files you should at least download the install sh script and the libraries in libs tar gz To install Free Pascal all t
152. irst unit cthreads on unix 171 Appendix E A sample gdb ini file Here you have a sample gdb ini file listing which gives better results when using gdb Under LINUX you should put this in a gdbinit file in your home directory or the current directory set print demangle off set gnutarget auto set verbose on set complaints 1000 dir rtl dosv2 set language c set print vtbl on set print object on set print sym on set print pretty on disp i Seip define pst set Spos amp Sarg0 set Sstrlen byte Spos print char Sarg0 st Sstrlent1 end document pst Print out a Pascal string end 172 Appendix F Options and settings In table F 1 a summary of available boolean compiler directives and the corresponding command line options are listed Other directives and the corresponding options are shown in table F 2 For more information about the command line options see chapter 5 page 23 For more information about the directives see the Programmers guide Table F 1 Boolean Options and directves Short long Opt Explanation SA SALIGN ON OFF Data alignment SB SBOOLEVAL ON OFF Boolean evaluation mode SC SASSERTIONS ON OFF Sa Include assertions SD SDEBUGINFO ON OFF g Include debug info SE Coprocessor emulation SF Far or near function ignored G Generate 80286 code ignored SGOTO ON OFF Sg Support GOTO a
153. is is a mandatory step 3 Set the Out S stream This is an open stream to which the beautified Pascal source will be written This is a mandatory step 4 Set the DiagS stream Any diagnostics will be written to this stream This step is optional If you don t set this no diagnostics are written 5 Set the CfgS stream A configuration is read from this stream see the previous section for more information about configuration This step is optional If you don t set this a default configuration is used 6 Set the Indent variable This is the number of spaces to use when indenting Tab characters are not used in the program This step is optional The indent variable is initialized to 2 7 Call PrettyPrint This will pretty print the source in Ins and write the result to Out S The function returns True if no errors occurred False otherwise So a minimal procedure would be Procedure CleanUpCode var Ins OutS PBufStream PPRinter TPrettyPrinter begin Ins New PBufStream Init ugly pp StopenRead TheBufSize OutS New PBufStream Init beauty pp StCreate TheBufSize PPrinter Create PPrinter Ins Ins PPrinter outS OutS PPrinter PrettyPrint end Using memory streams allows very fast formatting of code and is particularly suitable for editors 8 9 rstconv program The rstconv program converts the resource string files generated by the compiler when you use resource string sectio
154. ith a return value can have a return value set Error in binary constant Error in octal constant Error in hexadecimal constant 164 APPENDIX C COMPILER MESSAGES Error in integer constant These errors are reported when you tried using a constant expression that 1s invalid or whose value is out of range Invalid labeled opcode Asm syntax error error in reference Invalid Opcode Invalid combination of opcode and operands Invalid size in reference Invalid middle sized operand Invalid three operand opcode Assembler syntax error Invalid operand type You tried using an invalid combination of opcode and operands Check the syntax and if you are sure it is correct please contact one of the developers Unknown identifier The identifier you are trying to access does not exist or is not within the current scope Trying to define an index register more than once Trying to define a segment register twice Trying to define a base register twice You are trying to define an index segment register more than once Invalid field specifier The record or object field you are trying to access does not exist or is incor rect Invalid scaling factor Invalid scaling value Scaling value only allowed with index Allowed scaling values are 1 2 4 or 8 Cannot use SELF outside a method You are trying to access the SELF identifier for objects out side a method Invalid combination of prefix and opcode This opcode cannot be prefixed by t
155. l strip all debug and symbol information from the binary option Xs on the command line Skip debug information generation Do not generate debug information at all Generate debug symbol information Include debug information in the binary option g on the command line Please note that no debug information for units in the Run Time Library will be included unless a version of the RTL compiled with debug information is available Only units specific to the current project will have debug information included Generate also backtrace line information Will compile with debug information and will additionally include the lineinfo unit in the binary so that in case of an error the backtrace will contain the file names and line numbers of procedures in the call stack Option g1 on the command line Generate valgrind compatible debug info Generate debug information that can be read with valgrind a memory checking tool Profiling switches Tells the compiler whether or not profile code should be included in the binary No profile information Has no effect as it is the default Generate Profile code for gprof If checked profiling code is included in the binary option p on the command line Use another TTY for Debuggee An attempt will be made to redirect the output of the program being debugged to another window terminal whose file name should be entered here 6 11 8 The switches mode The IDE allows saving a set of compiler settin
156. lean variable LFNsupport If it is set to True then all system unit functions and Dos unit functions will use long file names if they are available This should be so on WINDOWS 95 and 98 but not on WINDOWS NT or WINDOWS 2000 The system unit will check this by calling DOS function 71A0h and checking whether long filenames are supported on the C drive It is possible to disable the long filename support by setting the LFNSupport variable to False but in general it is recommended to compile programs that need long filenames as native WINDOWS applications 7 3 Porting Delphi code Porting Delphi code should be quite painless The Delphi mode of the compiler tries to mimic Delphi as closely as possible This mode can be enabled using the Mdelphi command line switch or by inserting the following code in the sources before the unit or program clause SIFDEF FPC SMODE DELPHI SENDIF FPC This ensures that the code will still compile with both Delphi and FPC Nevertheless there are some things that will not work Delphi compatibility is relatively complete up to Delphi 7 New constructs in higher versions of Delphi notably the versions that work with NET are not supported 7 3 1 Missing language constructs At the level of language compatibility FPC is very compatible with Delphi it can compile most of FreeCLX the free Widget library that was shipped with Delphi 6 Delphi 7 and Kylix Currently the only missing l
157. leaves a lot of information in the program which strictly speaking isn t required for the execution of the program The surplus of information can be removed with a small program called strip The usage is simple Just type strip prog On the command line and the strip program will remove all unnecessary information from your program This can lead to size reductions of up to 30 You can use the Xs switch to let the compiler do this stripping automatically at program compile time The switch has no effect when compiling units Another technique to reduce the size of a program is to use smartlinking Normally units including the system unit are linked in as a whole It is however possible to compile units such that they can be smartlinked This means that only the functions and procedures that are actually used are linked in your program leaving out any unnecessary code The compiler will turn on smartlinking with the XX see page 5 1 4 switch This technique is described in full in the programmers guide 21 Chapter 4 Compiling problems 4 1 4 2 General problems IO error 2 at Under LINUX you can get this message at compiler startup It means typically that the compiler doesn t find the error definitions file You can correct this mistake with the Fr see page 5 1 3 option under LINUX Error File not found xxx or Error couldn t compile unit xxx This typically happens when your unit path isn t set corr
158. lidity of the method pointer prior to calling it Position independent code Generate PIC code Create smartlinkable units Create smartlinkable units Optimizations What optimizations should be used when compiling Generate faster code Corresponds to the OG command line option Generate smaller code Corresponds to the Og command line option More information on these switches can be found in section 5 1 4 page 25 The processor tab of the compiler options dialog is shown in figure 6 25 71 CHAPTER 6 THE IDE Figure 6 25 The processor selection tab Compiler Switches Processor Target processor 5 ATHLON64 In the processor dialog the target processor can be set The compiler can use different optimizations for different processors The verbose tab of the compiler options dialog is shown in figure 6 26 In this dialog the following verbosity options can be set on the command line v see page 5 1 2 Warnings Generate warnings Corresponds to vw on the command line Notes Generate notes Corresponds to vn on the command line Hints Generate hints Corresponds to vh on the command line General info Generate general information Corresponds to vi on the command line User tried info Generate information on used and tried files Corresponds to vut on the command line All Switch on full verbosity Corresponds to va on the command line Show all procedures if error If an error using overloaded procedure
159. ll mark all exception re lated keywords as keywords also in Turbo Pascal or FPC mode This can be used to check for code which should be mode neutral as much as possible Un Do not check the unit name Normally the unit name is the same as the filename This option allows them to be different Us Compile a system unit This option causes the compiler to define only some very basic types 30 CHAPTER 5 COMPILER CONFIGURATION 5 2 Using the configuration file Using the configuration file fpc cfg is an alternative to command line options When a configuration file is found it is read and the lines in it are treated as if you typed them on the command line They are treated before the options that you type on the command line You can specify comments in the configuration file with the sign Everything from the on will be ignored The algorithm to determine which file is used as a configuration file is decribed in 3 1 5 on page 20 When the compiler has finished reading the configuration file it continues to treat the command line options One of the command line options allows you to specify a second configuration file Specifying foo on the command line will open file foo and read further options from there When the compiler has finished reading this file it continues to process the command line The configuration file allows a type of preprocessing It understands the following directives which you should place star
160. lled e fpc exe under WINDOWS OS 2 and DOS e fpc under most other operating systems To compile a program e g demo text hello pp copy the program to your current working directory and simply type fpc hello at the command prompt If you don t have a configuration file then you may need to tell the compiler where it can find the units for instance as follows fpc Fuc AppANNNlunitsli386 go32v21rt1 hello under DOS and under LINUX you could type fpc Fu usr lib fpc NNN units i386 linux rtl hello replace NNN with the version number of Free Pascal that you are using This is of course assuming that you installed under C PP or usr lib fpc NNN respectively If you got no error messages the compiler has generated an executable called hello exe under DOS 0s 2 or WINDOWS or hello no extension under UNIX and most other operating systems To execute the program simply type hello or hello on Unices where the current directory usually is not in the PATH If all went well you should see the following friendly greeting Hello world Remark Chapter 3 Compiler usage Here we describe the essentials to compile a program and a unit For more advanced uses of the compiler see the section on configuring the compiler and the Programmers guide The examples in this section suppose that you have an fpc cfg which is set up correctly and which contains at least the path setting for the RTL units In principle
161. llowed in the implementation part At least one unit must contain the other one in the implement ation section Fatal Can t compile unit arg1 no sources available A unit was found that needs to be recom piled but no sources are available Fatal Can t find unit argl used by arg2 You tried to use a unit of which the PPU file isn t found by the compiler Check your configuration file for the unit paths Warning Unit argl was not found but arg2 exists This error message is no longer used Fatal Unit argl searched but arg2 found DOS truncation of 8 letters for unit PPU files may lead to problems when unit name is longer than 8 letters Warning Compiling the system unit requires the Us switch When recompiling the system unit it needs special treatment the Us switch must be specified Fatal There were arg1 errors compiling module stopping When the compiler encounters a fatal error or too many errors in a module then it stops with this message 159 APPENDIX C COMPILER MESSAGES Load from arg1 arg2 unit arg3 When you use the vu flag which unit is loaded from which unit 1s shown Recompiling arg1 checksum changed for arg2 The unit is recompiled because the checksum of a unit it depends on has changed Recompiling arg1 source found only When you use the vu flag these messages tell you why the current unit is recompiled Recompiling unit static lib is older than ppufile When you use the vu flag the compiler war
162. lt 7fffffff This can cause random errors in code like if p gt q Error Interface type arg1 has no valid GUID When applying the as operator to an interface or class the desired interface i e the right operand of the as operator must have a valid GUID C 5 Symbol handling This section lists all the messages that concern the handling of symbols This means all things that have to do with procedure and variable names Error Identifier not found arg1 The compiler doesn t know this symbol Usually happens when you misspell the name of a variable or procedure or when you forget to declare a vari able Fatal Internal Error in SymTableStack An internal error occurred in the compiler If you en counter such an error please contact the developers and try to provide an exact description of the circumstances in which the error occurs Error Duplicate identifier arg1 The identifier was already declared in the current scope 151 APPENDIX C COMPILER MESSAGES Hint Identifier already defined in argl at line arg2 The identifier was already declared in a pre vious scope Error Unknown identifier arg1 The identifier encountered has not been declared or is used outside the scope where it is defined Error Forward declaration not solved arg1 This can happen in two cases e You declare a function in the interface part or with a forward directive but do not implement it e You reference a type which isn t decla
163. ly with a name of length 1 Error No DEFFILE entry can be generated for unit global vars Error Compile without WD option You need to compile this file without the WD switch on the command line Fatal You need ObjF pc S2 or Delphi Sd mode to compile this module You need to use MOD OBJFPC or SMODE DELPHI to compile this file Or use the corresponding command line switch either Mobjfpc or MDelphi E Error Can t export with index under argl1 Exporting of functions or procedures with a specified index is not supported on this target Error Exporting of variables is not supported under arg1 Exporting of variables is not supported on this target Error Improper GUID syntax The GUID indication does not have the proper syntax It should be of the form XXXXXXXXXXXX XXXX XXXX XXXXXXXXXXXX Where each X represents a hexadecimal digit Warning Procedure named arg1 not found that is suitable for implementing the arg2 arg3 The compiler cannot find a suitable procedure which implements the given method of an inter face A procedure with the same name is found but the arguments do not match Error interface identifier expected This happens when the compiler scans a class declaration that contains interface function name mapping code like this type TMyObject class TObject IDispatch function IUnknown QueryInterface MyQueryInterface and the interface before the dot is not listed in th
164. mand line It can also be started from a graphical user interface such as WINDOWS Under WINDOWS it is possible to switch between windowed mode and full screen mode by pressing ALT ENTER 6 1 2 IDE command line options When starting the IDE command line options can be passed fp option option lt file name gt Option is one of the following switches the option letters are case insensitive N DOS only Do not use long file names WINDOWS 95 and later versions of WINDOWS provide an interface to DOS applications to access long file names The IDE uses this interface by default to access files Under certain circumstances this can lead to problems This switch tells the IDE not to use the long filenames Cfilename Read IDE options from filename There should be no whitespace between the file name and the C F Use alternative graphic characters This can be used to run the IDE on LINUX in an X term or through a telnet session 35 CHAPTER 6 THE IDE R After starting the IDE change automatically to the directory which was active when the IDE exited the last time S Disable the mouse When this option is used the use of a mouse is disabled even if a mouse is present Tttyname LINUX Unix only Send program output to tty ttyname This avoids having to con tinually switch between program output and the IDE The files given at the command line are loaded into edit windows automatically Remark Under DOS Win
165. missing and link ing will probably fail Check your paths Error Error while linking Generic error while linking Error Can t call the linker switching to external linking An error occurred when calling an ex ternal linker The compiler will produce a script that can be used to assemble and link the program Info Linking arg1 An informational message showing which program or library is being linked Error Util arg1 not found switching to external linking An external tool was not found The compiler will produce a script that can be used to assemble and link or postprocess the program Using util argl An informational message showing which external program usually a postproces sor is being used Error Creation of Executables not supported Creating executable programs is not supported for this platform because it was not yet implemented in the compiler Error Creation of Dynamic Shared Libraries not supported Creating dynamically loadable li braries is not supported for this platform because it was not yet implemented in the compiler Info Closing script arg1 Informational message showing when writing of the external assembling and linking script is finished Error resource compiler not found switching to external mode An external resource compiler was not found The compiler will produce a script that can be used to assemble compile resources and link or postprocess the program Info Compiling resource arg1 An i
166. mpiled with a different version of the compiler and cannot be read PPU is compiled for another processor This unit file was compiled for a different processor type and cannot be read PPU is compiled for an other target This unit file was compiled for a different target and cannot be read PPU Source argl When you use the vu flag the unit source file name is shown Writing arg1 When you specify the vu switch the compiler will tell you where it writes the unit file Fatal Can t Write PPU File An error occurred when writing the unit file Fatal Error reading PPU File This means that the unit file was corrupted and contains invalid information Recompilation will be necessary Fatal unexpected end of PPU File Unexpected end of file This may mean that the PPU file is corrupted Fatal Invalid PPU File entry arg1 The unit the compiler is trying to read is corrupted or gener ated with a newer version of the compiler Fatal PPU Dbx count problem There is an inconsistency in the debugging information of the unit Error Illegal unit name argl1 The name of the unit does not match the file name Fatal Too much units Free Pascal has a limit of 1024 units in a program You can change this behavior by changing the maxunits constant in the fmodule pas file of the compiler and recompiling the compiler Fatal Circular unit reference between argl and arg2 Two units are using each other in the inter face part This is only a
167. mplemented Register argl weight arg2 arg3 Debugging message Shown when the compiler considers a vari able for keeping in the registers Stack frame is omitted Some procedure functions do not need a complete stack frame so it is omitted This message will be displayed when the vd switch is used Error Object or class methods can t be inline You cannot have inlined object methods Error Procvar calls cannot be inline A procedure with a procedural variable call cannot be in lined Error No code for inline procedure stored The compiler couldn t store code for the inline proce dure Error Element zero of an ansi wide or longstring can t be accessed use set length instead You should use set length to set the length of an ansi wide longstring and length to get the length of such string type Error Constructors or destructors can not be called inside a with clause Inside a with clause you cannot call a constructor or destructor for the object you have in the with clause Error Cannot call message handler methods directly A message method handler method cannot be called directly if it contains an explicit Sel argument Error Jump in or outside of an exception block It is not allowed to jump in or outside of an ex ception block like try finally end For example the following code will produce this error label 1 try if not final then goto 1 this line will cause an error finally end Ty
168. n 8 bits This may lead to range check errors The in operator currently only supports a left operand which fits within a byte In the case of enumerations the size of an element of an enumeration can be controlled with the SPACKENUM or Zn switches 149 APPENDIX C COMPILER MESSAGES Warning Type size mismatch possible loss of data range check error There is an assignment to a smaller type than the source type This means that this may cause a range check error or may lead to possible loss of data Hint Type size mismatch possible loss of data range check error There is an assignment to a smaller type than the source type This means that this may cause a range check error or may lead to possible loss of data Error The address of an abstract method can t be taken An abstract method has no body so the address of an abstract method can t be taken Error Assignments to formal parameters and open arrays are not possible You are trying to as sign a value to a formal untyped var const or out parameter or to an open array Error Constant Expression expected The compiler expects an constant expression but gets a variable expression Error Operation arg1 not supported for types arg2 and arg3 The operation is not al lowed for the supplied types Error Illegal type conversion arg1 to arg2 When doing a type cast you must take care that the sizes of the variable and the destination type are the sam
169. n label identifier with an prefix Internal error in Findtype Internal Error in ConcatOpcode Internal Errror converting binary Internal Errror converting hexadecimal Internal Errror converting octal Internal Error in BuildScaling Internal Error in Build Constant internal error in BuildReference internal error in HandleExtend Internal error in ConcatLabeledInstr These errors should never occur If they do then you have found a new bug in the assembler parsers Please contact one of the developers Opcode not in table operands not checked This warning only occurs when compiling the system unit or related files No checking is performed on the operands of the opcodes CODE and DATA not supported This Turbo Pascal construct is not supported SEG and OFFSET not supported This Turbo Pascal construct is not supported Modulo not supported Modulo constant operation is not supported Floating point binary representation ignored Floating point hexadecimal representation ignored Floating point octal representation ignored These warnings occur when a floating point constant 1s declared in a base other than decimal No conversion can be done on these formats You should use a decimal representation instead Identifier supposed external This warning occurs when a symbol is not found in the symbol table It is therefore considered external Functions with void return value can t return any value in asm code Only routines w
170. n the vd switch is used this line tells you what the target operating system is Using executable path argl When the vt switch is used this line tells you where the compiler looks for its binaries Using unit path argl When the vt switch is used this line tells you where the compiler looks for compiled units You can set this path with the Fu option Using include path argl When the vt switch is used this line tells you where the compiler looks for its include files files used in I xxx statements You can set this path with the Fi option Using library path arg When the vt switch is used this line tells you where the compiler looks for the libraries You can set this path with the F 1 option Using object path argl When the vt switch is used this line tells you where the compiler looks for object files you link in files used in L xxx statements You can set this path with the Fo option Info argl lines compiled arg2 sec arg3 When the vi switch is used the compiler reports the number of lines compiled and the time it took to compile them real time not program time Fatal No memory left The compiler doesn t have enough memory to compile your program There are several remedies for this 126 APPENDIX C COMPILER MESSAGES Info e If you re using the build option of the compiler try compiling the different units manu ally e If you re compiling a huge program split it up into units and
171. n the command line 6 10 3 The ASCII table The tools menu also provides an ASCII table ToolslAscii table The ASCII table can be used to look up ASCII codes as well as to insert characters into the window which was active when invoking the table To reveal the ASCII code of a character in the table move the cursor onto this character or click it with the mouse The decimal and hex values of the character are shown at the bottom on the ASCII table window To insert a character into an editor window either 1 using the mouse double click it or 2 using the keyboard press ENTER while the cursor is on it Suggestions for improvement or better yet patches that improve the algorithm are always welcome 60 CHAPTER 6 THE IDE This is especially useful for pasting graphical characters in a constant string The ASCII table remains active till another window is explicitly activated thus multiple characters can be inserted at once The ASCII table is shown in figure 6 18 Figure 6 18 The ASCII table i e tte Boke 7 PEA TUE a E Ad 48 CO 8123456789 c GABCDEFGHI JKLMNOPORS TUUWRYZLS 1 abcdef ghi uo ON UOC A E dodwyd EYRE Cii adadp te11iAAE t MEL Haat AL Ut Hl i abr Who pra ihome jet s 4220 g Char Decimal A Hex HA 6 10 4 The calculator The calculator allows quick calculations without leaving the IDE It is a simple calculator since it does not take care of operator preceden
172. n you define it even when it was declared earlier with Forward In Turbo Pascal compatibility mode there is no function overloading hence you can omit the parameter list Procedure a L Longint Forward Procedure a No need to repeat the L Longint begin end 93 CHAPTER 7 PORTING AND PORTABLE CODE e Recursive function calls are handled differently Consider the following example Function expr Longint begin Expr L Writeln Expr end In Turbo Pascal compatibility mode the function will be called recursively when the writeln statement is processed In Free Pascal the function result will be printed In order to call the function recursively under Free Pascal you need to implement it as follows Function expr Longint begin Expr L Writeln Expr end e Any text after the final End statement is ignored Normally this text is processed too e You cannot assign procedural variables to untyped pointers so the following is invalid a Procedure b Pointer begin b a Error will be generated e The operator is typed when applied on procedures e You cannot nest comments Remark The MemAvail and MaxAvail functions are no longer available in Free Pascal as of version 2 0 The reason for this incompatibility follows On modern operating systems the idea of Available Free Memory is not valid for an application The reasons are 1 One proc
173. ncerning the reading of assembler blocks R on the command line and the generated assembler A on the command line Processor Here the target processor can be selected On each tab page there are two entry boxes the first for Conditional defines and the second for additional compiler arguments The symbols and arguments should be separated with semi colons The syntax tab of the compiler options dialog is shown in figure 6 23 69 CHAPTER 6 THE IDE Figure 6 23 The syntax options tab C IS AS Syntax Suntax Switches BI Stop after first error In the syntax options dialog the following options can be set Stop after first error when checked the compiler stops after the first error Normally the compiler continues compiling till a fatal error is reached Se see page 5 1 5 on the command line Allow label and goto Allow the use of label declarations and goto statements Sg see page 5 1 5 on the command line Enable macros Allow the use of macros Sm see page 5 1 5 Allow inline Allow the use of inlined functions Sc see page 5 1 5 on the command line Include assertion code Include Assert statements in the code Load kylix compat unit Load the Kylix compatibility unit Allow STATIC in objects Allow the Static modifier for object methods St see page 5 1 5 on the command line C like operators Allows the use of some extended operators such as etc Sc see page 5 1 5 on the comm
174. nd Label SHINTS ON OFF vh Show hints SH SLONGSTRINGS ON OFF Sh Use ansistrings SI SIOCHECKS ON OFF Ci Check I O operation result SINLINE ON OFF Si Allow inline code SL SLOCALSYMBOLS ON OFF Local symbol information SM STYPEINFO ON OFF Generate RTTI for classes SMMX ON OFF Intel MMX support SN Floating point support SNOTES ON OFF vn Emit notes O Support overlays ignored SP SOPENSTRINGS ON OFF Support open strings SQ SOVERFLOWCHECKS ON OFF Co Overflow checking SR SRANGECHEKS ON OFF Cr Range checks S Ct Stack checks SSMARTLINK ON OFF CX Use smartlinking STATIC ON OFF St Allow use of static ST STYPEDADDRESS ON OFF Typed addresses 173 APPENDIX F OPTIONS AND SETTINGS Table F 2 Options and directives Short long Opt Explanation SAPPTYPE W Application type Win32 0S2 SASMMODE ZR Assembler reader mode SDEFINE d Define symbol SDESCRIPTION Set program description SELSE Conditional compilation switch SENDIF Conditional compilation end SFATAL Report fatal error SHINT Emit hint message I file SINCLUDE Include file or literal text SIF Conditional compilation start SIFDEF NAM Conditional compilation start SIFNDEF Conditional compilation start SIFOPT Conditional compilation start SINCLUDEPATH Fi Set include path SINFO Emit informat
175. nd text Prompt on replace Before a replacement is made the IDE will ask for confirmation If the dialog is closed with the OK button only the next occurrence of the the search text will be replaced If the dialog is closed with the Change All button all occurrences of the search text will be replaced 6 7 The symbol browser The symbol browser allows searching all occurrences of a symbol A symbol can be a variable type procedure or constant that occurs in the program or unit sources To enable the symbol browser the program or unit must be compiled with browser information This can be done by setting the browser information options in the compiler options dialog The IDE allows to browse several types of symbols Procedures Allows quick jumping to a procedure definition or implementation Objects Quickly browse for an object Modules Browse a module Globals Browse any global symbol Arbitrary symbol Browse an arbitrary symbol In all cases first a symbol to be browsed must be selected After that a browse window appears In the browse window all locations where the symbol was encountered are shown Selecting a location and pressing the space bar will cause the editor to jump to that location the line containing the symbol will be highlighted If the location is in a source file that is not yet displayed a new window will be opened with the source file loaded After the desired location has been reached the b
176. nd time When you request debug messages vd the compiler tells you what units it recompiles for the second time Error No property found to override You want to override a property of a parent class when there is in fact no such property in the parent class Error Only one default property is allowed You specified a property as Default but the class already has a default property and a class can have only one default property Error The default property must be an array property Only array properties of classes can be made default properties Error Virtual constructors are only supported in class object model You cannot have virtual con structors in objects You can only have them in classes Error No default property available You are trying to access a default property of a class but this class or one of its ancestors doesn t have a default property Error The class can t have a published section use the M switch If you want a published section in a class definition you must use the M switch which turns on generation of type information Error Forward declaration of class arg1 must be resolved here to use the class as ancestor To be able to use an object as an ancestor object it must be defined first This error occurs in the following situation G Type ParentClas Class ChildClass Class ParentClass end where ParentClass is declared but not defined Error Local operators not supported Y
177. ndow will restore the old size of the window Pressing the F5 key has the same effect as clicking that arrow The same effect can be achieved with the menu item WindowlZoom Windows and dialogs which aren t resizeable can t be zoomed either The right edge and bottom edges of a window contain scrollbars They can be used to scroll the window contents with the mouse The arrows at the ends of the scrollbars can be clicked to scroll the contents line by line Clicking on the dotted area between the arrows and the cyan coloured rectangle will scroll the window s content page by page By dragging the rectangle the content can be scrolled continuously The star and the numbers in the lower left corner of the window display information about the con tents of the window They are explained in the section about the editor see section 6 5 page 47 6 3 2 Sizing and moving windows A window can be moved and sized using the mouse and the keyboard To move a window e Using the mouse click on the title bar and drag the window with the mouse e Using the keyboard go into the size move mode by pressing CTRL F5 or selecting the menu item WindowlSize Move The window frame will change to green to indicate that the IDE is in size move mode Now the cursor keys can be used to move the window Press ENTER to leave the size move mode In this case the window will keep its size and position Alternatively pressing ESC will restore the old position
178. ne action is executed Change dir on open When a file is opened the directory of that file is made the current work ing directory 6 12 2 The desktop The desktop preferences dialog allows to specify what elements of the desktop are saved across sessions i e they are saved when the IDE is left and they are again restored when the IDE is started the next time They are saved in the file fp dsk The desktop preferences dialog is shown in figure 6 34 Figure 6 34 The desktop preferences dialog istory lists The following elements can be saved and restored across IDE sessions History lists Most entry boxes have a history list where previous entries are saved and can be se lected When this option is checked these entries are saved in the desktop file On by default Clipboard content When checked the contents of the clipboard are also saved to disk Off by default 79 CHAPTER 6 THE IDE Watch expressions When checked all watch expressions are saved in the desktop file Off by de fault Breakpoints When checked all breakpoints with their properties are saved in the desktop file Off by default Open windows When checked the list of files in open editor windows is saved in the desktop file and the windows will be restored the next time the IDE is run On by default Symbol information When checked the information for the symbol browser is saved in the desktop file Off by default CodeComplete wordlist
179. nes Show information on units being loaded Show names of files being opened Show names of procedures and functions being processed Notify on each conditional being processed Show names of macros being defined Show additional debugging information No messages This is useful for overriding the default setting in the configuration file Show all procedure declarations if an overloaded function error occurs Show information about the executable Win32 platform only Format errors in RHIDE GCC compatibility mode Show all possible information this is the same as specifying all options bs Tells the compiler to write filenames using the full path Write copious debugging information to file focdebug txt Mainly for the compiler developers e p Write parse tree to file tree log Intended for compiler developers 5 1 3 Options concerning files and directories exxx Specify xxx as the directory containing the executables for the programs as the assembler and 1d the linker FaXYZ load units XYZ after the system unit but before any other unit is loaded XYZ is a comma separated list of unit names This can only be used for programs and has the same effect as if XYZ were inserted as the first item in the program s uses clause FcXXX Set the input codepage to XXX Experimental FCxxx Set the RC compiler resource compiler binary name to Xxx FD Same as e Fexxx Write errors
180. nformational message showing which resource is being com piled 157 APPENDIX C COMPILER MESSAGES unit argl can t be statically linked switching to smart linking Static linking was requested but a unit which is not statically linkable was used unit argl can t be smart linked switching to static linking Smart linking was requested but a unit which is not smart linkable was used unit argl can t be shared linked switching to static linking Shared linking was requested but a unit which is not shared linkable was used Error unit argl can t be smart or static linked Smart or static linking was requested but a unit which cannot be used for either was used Error unit argl can t be shared or static linked Shared or static linking was requested but a unit which cannot be used for either was used Calling resource compiler arg1 with arg2 as command line An informational message show ing which command line is used for the resource compiler C 8 Executable information messages This section lists all messages that the compiler emits when an executable program is produced and only when the internal linker is used Fatal Can t post process executable arg1 Fatal error when the compiler is unable to post process an executable Fatal Can t open executable arg Fatal error when the compiler cannot open the file for the exe cutable Size of Code argl bytes Informational message showing the size of the produ
181. ni tial value in Delphi mode Error Abstract methods shouldn t have any definition with function body Abstract methods can only be declared you cannot implement them They should be overridden by a descendant class Error This overloaded function can t be local must be exported You are defining an overloaded function in the implementation part of a unit but there is no corresponding declaration in the interface part of the unit Warning Virtual methods are used without a constructor in arg1 If you declare objects or classes that contain virtual methods you need to have a constructor and destructor to initialize them The compiler encountered an object or class with virtual methods that doesn t have a construc tor destructor pair 137 APPENDIX C COMPILER MESSAGES Macro defined argl When vc is used the compiler tells you when it defines macros Macro undefined argl When vc is used the compiler tells you when it undefines macros Macro arg set to arg2 When vc is used the compiler tells you what values macros get Info Compiling arg1 When you turn on information messages vi the compiler tells you what units it is recompiling Parsing interface of unit arg1 This tells you that the reading of the interface of the current unit has started Parsing implementation of argl This tells you that the code reading of the implementation of the current unit library or program starts Compiling arg1 for the seco
182. ns if the static library of the unit is older than the unit file itself Recompiling unit shared lib is older than ppufile When you use the vu flag the compiler warns if the shared library of the unit is older than the unit file itself Recompiling unit obj and asm are older than ppufile When you use the vu flag the compiler warns if the assembler or object file of the unit is older than the unit file itself Recompiling unit obj is older than asm When you use the vu flag the compiler warns if the assembler file of the unit is older than the object file of the unit Parsing interface of argl When you use the vu flag the compiler warns that it starts parsing the interface part of the unit Parsing implementation of argl When you use the vu flag the compiler warns that it starts pars ing the implementation part of the unit Second load for unit arg1 When you use the vu flag the compiler warns that it starts recompiling a unit for the second time This can happen with interdependent units PPU Check file arg1 time arg2 When you use the vu flag the compiler shows the filename and date and time of the file on which a recompile depends Warning Can t recompile unit arg1 but found modifed include files A unit was found to have modified include files but some source files were not found so recompilation is impossible File argl is newer than PPU file arg2 A modified source file for a compiler unit was found Trying to use
183. ns to po files that can be understood by the GNU msgfmt program Its usage is very easy it accepts the following options 108 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL i file Use the specified file instead of stdin as input file This option is optional 0 file Write output to the specified file This option is required f format Specify the output format At the moment only one output format is supported po for GNU gettext po format It is the default format As an example rstconv i resdemo rst o resdemo po will convert the resdemo rst file to resdemo po More information on the rstconv utility can be found in the Programmers guide under the chapter about resource strings 8 10 unitdiff program 8 10 1 Synopsis unitdiff shows the differences between two unit interface sections unitdiff disable arguments disable private disable protected help lang language list output filename sparse filel file2 8 10 2 Description and usage Unitdiff scans one or two Free Pascal unit source files and either lists all available identifiers or describes the differences in identifiers between the two units You can invoke unitdiff with an input filename as the only required argument It will then simply list all available identifiers The regular usage is to invoke unitdiff with two arguments unitdiff inputl input2 Invoked like this 1t will show the difference in interfa
184. nt supported platforms It does not attempt to give an exhaustive list of all supported commands nor a definition of the Pascal language Look at the Reference guide for these things For a description of the possibilities and the inner workings of the compiler see the Programmers guide In the appendices of this document you will find lists of reserved words and compiler error messages with descriptions This document describes the compiler as it is functions at the time of writing First consult the README and FAQ files distributed with the compiler The README and FAQ files are in case of conflict with this manual authoritative 1 2 About the compiler Free Pascal is a 32 and 64 bit Pascal compiler The current version 2 2 can compile code for the following processors e Intel 1386 and higher 1486 Pentium family and higher e AMD64 x86_64 e PowerPC e PowerPC64 e SPARC e ARM e The m68K processor is supported by an older version The compiler and Run Time Library are available for the following operating systems e DOS e LINUX e AMIGA version 0 99 5 only CHAPTER 1 INTRODUCTION e WINDOWS e MacOS X e 0s 2 optionally using the EMX package so it also works on DOS Windows e FREEBSD e BEOS e SOLARIS e NETBSD e NETWARE e OPENBSD e MorphOS e Symbian The complete list is at all times available on the Free Pascal website Free Pascal is designed to be as much as possible source compatible with Turbo Pa
185. nvalid floating point operation Can occur if you try to calculate the square root or logarithm of a negative number 210 Object not initialized When compiled with range checking on a program will report this error if you call a virtual method without having called its object s constructor 211 Call to abstract method Your program tried to execute an abstract virtual method Abstract methods should be overridden and the overriding method should be called 212 Stream registration error This occurs when an invalid type is registered in the objects unit 213 Collection index out of range You are trying to access a collection item with an invalid index objects unit 214 Collection overflow error The collection has reached its maximal size and you are trying to add another element objects unit 215 Arithmetic overflow error This error is reported when the result of an arithmetic operation is outside of its supported range Contrary to Turbo Pascal this error is only reported for 32 bit or 64 bit arithmetic overflows This is due to the fact that everything is converted to 32 bit or 64 bit before doing the actual arithmetic operation 216 General Protection fault The application tried to access invalid memory space This can be caused by several problems 1 Dereferencing a nil pointer 2 Trying to access memory which is out of bounds for example calling move with an invalid length 217 Unhandled exception occurred An exception o
186. o Pascal in a Free Pascal project 13 The Free Pascal Text Rec structure for internal description of files is not binary compatible with TP or Delphi 14 Sets are by default 4 bytes in Free Pascal this means that some typecasts which were possible in Turbo Pascal are no longer possible in Free Pascal However there is a switch to set the set size see Programmers guide for more information 15 A file is opened for output only using fmOutput when it is opened with Rewrite In order to be able to read from it it should be reset with Reset 16 Turbo Pascal destructors allowed parameters This is not permitted in Free Pascal by default in Free Pascal Destructors cannot have parameters This restriction can be removed by using the So switch 17 Turbo Pascal permits more than one destructor for an object In Free Pascal there can be only one destructor This restriction can also be removed by using the So switch 18 The order in which expressions are evaluated is not necessarily the same In the following expression a g 2 3 it is not guaranteed that g 2 will be evaluated before f 3 19 In Free Pascal you need to use the address 2 operator when assigning procedural variables 7 2 2 Things which are extra Here we give a list of things which are possible in Free Pascal but which didn t exist in Turbo Pascal or Delphi 1 Free Pascal functions can also return complex types such as records and arrays
187. o assign a local procedure function to a procedure variable because the calling convention of a local procedure function is different You can only assign local procedure function to a void pointer Error Can t assign values to an address It is not allowed to assign a value to an address of a variable constant procedure or function You can try compiling with So if the identifier is a procedure variable Error Can t assign values to const variable It s not allowed to assign a value to a variable which is declared as a const This is normally a parameter declared as const To allow changing the value pass the parameter by value or a parameter by reference using var Error Array type required If you are accessing a variable using an index lt x gt then the type must be an array In FPC mode a pointer is also allowed Error interface type expected but got arg1 The compiler expected to encounter an interface type name but got something else The following code would produce this error Type TMyStream Class TStream Integer 148 APPENDIX C COMPILER MESSAGES Warning Mixing signed expressions and longwords gives a 64bit result If you divide or calcu late the modulus of a signed expression by a longword or vice versa or if you have overflow and or range checking turned on and use an arithmetic expression div mod in which both signed numbers and longwords appear then everything has to be ev
188. o read the configuration file found source file name arg1 Additional information about options Displayed when you have the debug option turned on Error Unknown code page An unknown code page for the source files was requested The com piler is compiled with support for several code pages built in The requested code page is not in that list You will need to recompile the compiler with support for the codepage you need Fatal Config file argl is a directory Directories cannot be used as configuration files Warning Assembler output selected argl cannot generate debug info debugging disabled The selected assembler output cannot generate debugging information debugging option is there fore disabled Warning Use of ppc386 cfg is deprecated please use fpc cfg instead Using ppc386 cfg is still sup ported for historical reasons however for a multiplatform system the naming makes no sense anymore Please continue to use fpc cfg instead C 11 Assembler reader errors This section lists the errors that are generated by the inline assembler reader They are not the messages of the assembler itself C 11 1 General assembler errors Divide by zero in asm evaluator This fatal error is reported when a constant assembler expression performs a division by zero Evaluator stack overflow Evaluator stack underflow These fatal error is reported when a con stant assembler expression is too big to be evaluated by the constant parser Tr
189. object or class instance it operates on which can not be known at compile time Error Default value can only be assigned to one parameter It is not possible to specify a default value for several parameters at once The following is invalid Procedure MyProcedure A B Integer 0 Instead this should be declared as Procedure MyProcedure A Integer 0 B Integer 0 Error Default parameter required for arg1 The specified parameter requires a default value 142 APPENDIX C COMPILER MESSAGES Warning Use of unsupported feature You re trying to force the compiler into doing something 1t cannot do yet Hint C arrays are passed by reference Any array passed to a C function is passed by a pointer i e by reference Error C array of const must be the last argument You can not add any other argument after an array of const for cdecl functions as the size pushed on stack for this argument is not known Hint Type argl redefinition This is an indicator that a previously declared type is being rede fined as something else This may or may not be a potential source of errors Warning cdecl ared functions have no high parameter Functions declared with the cdec1 mod ifier do not pass an extra implicit parameter Warning cdecl ared functions do not support open strings Openstring is not supported for func tions that have the cdec1 modifier Error Cannot initialize variables declared as threadvar Varia
190. oint at a specified line or function awatch Seta watch point for an expression A watch point stops execution of your program when ever the value of an expression is either read or written In appendix E a sample init file for gdb is presented It produces good results when debugging Free Pascal programs For more information refer to the gdb User Manual or use the help function in gdb The text mode IDE and Lazarus both use GDB as a debugging backend It may be preferable to use that as they hide much of the details of the debugger in an easy to use user interface 10 3 Caveats when debugging with gdb There are some peculiarities of Free Pascal which you should be aware of when using gdb We list the main ones here 1 Free Pascal generates information for GDB in uppercase letters This is a consequence of the fact that Pascal is a case insensitive language So when referring to a variable or function you need to make its name all uppercase As an example if you want to watch the value of a loop variable count you should type watch COUNT Or if you want to stop when a certain function e g MyFunction is called type break MYFUNCTION 2 gdb does not know sets 3 gdb doesn t know strings Strings are represented in gdb as records with a length field and an array of char containing the string You can also use the following user function to print strings define pst set Spos amp Sarg0 set Sstrlen byte Sp
191. only this is one of 10 13 10 or 13 LFNSupport A boolean that indicates whether the system supports long filenames i e is not lim ited to MS DOS 8 3 filenames DirectorySeparator The character which acts as a separator between directory parts of a path DriveSeparator For systems that support drive letters this is the character that is used to separate the drive indication from the path PathSeparator The character used to separate items in a list notably a PATH maxExitCode The maximum value for a process exitcode MaxPathLen The maximum length of a filename including a path FileNameCaseSensitive A boolean that indicates whether filenames are handled case sensitively UnusedHandle A value used to indicate an unused invalid file handle StdInputHandle The value of the standard input file handle This is not always O zero as is commonly the case on Unices StdOutputHandle The value of the standard output file handle This is not always 1 as is commonly the case on Unices StdErrorHandle The value of the standard diagnostics output file handle This is not always 2 as is commonly the case on Unices CtrIZMarksEOF A boolean that indicates whether the 26 character marks the end of a file an old MS DOS convention To ease writing portable filesystem code the Free Pascal file routines in the system unit and sysutils unit treat the common directory separator characters and as equivalent That means that if you u
192. operators such as the AS operator are only applicable to classes or COM interfaces Error Constant packed arrays are not yet supported You cannot declare a bit packed array as a typed constant Error Incompatible type for arg no arg1 Got arg2 expected Bit Packed Array The com piler expects a bit packed array as the specified parameter Error Incompatible type for arg no arg1 Got arg2 expected not packed Array The com piler expects a regular i e not packed array as the specified parameter Error Elements of packed arrays cannot be of a type which need to be initialised Support for packed arrays of types that need initialization such as ansistrings or records which contain an sistrings is not yet implemented 150 APPENDIX C COMPILER MESSAGES Error Constant packed records and objects are not yet supported You cannot declare a bit packed array as a typed constant at this time Warning Arithmetic arg1 on untyped pointer is unportable to T suggest typecast Addition subtraction from an untyped pointer may work differently in T Use a typecast to a typed pointer Error Can t take address of a subroutine marked as local The address of a subroutine marked as local can t be taken Error Can t export subroutine marked as local from a unit A subroutine marked as local can t be exported from a unit Error Type is not automatable arg1 Only byte integer longint smallint currency sin
193. os print char Sarg0 st Sstrlent1 end document pst Print out a Pascal string end If you insert it in your gdb ini file you can look at a string with this function There is a sample gdb ini in appendix E 117 CHAPTER 10 DEBUGGING YOUR PROGRAMS 4 Objects are difficult to handle mainly because gdb is oriented towards C and C The workaround implemented in Free Pascal is that object methods are represented as functions with an extra parameter this all lowercase The name of this function is a concatenation of the object type and the function name separated by two underscore characters For example the method TPoint Draw would be converted to TPOINT__DRAW and you could stop at it by using break TPOINT__DRAW 5 Global overloaded functions confuse gdb because they have the same name Thus you cannot set a breakpoint at an overloaded function unless you know its line number in which case you can set a breakpoint at the starting line number of the function 10 4 Support for gprof the GNU profiler You can compile your programs with profiling support For this you just have to use the compiler switch pg The compiler will insert the necessary stuff for profiling When you have done this you can run your program as you would normally run it yourexe Where yourexe is the name of your executable When your program finishes a file called gmon out is generated Then you can start the profiler to see the
194. ou cannot overload locally i e inside procedures or func tion definitions Error Procedure directive arg1 not allowed in interface section This procedure directive is not allowed in the interface section of a unit You can only use it in the implementation section Error Procedure directive arg1 not allowed in implementation section This procedure direc tive is not allowed in the implementation section of a unit You can only use it in the interface section 138 APPENDIX C COMPILER MESSAGES Error Procedure directive arg1 not allowed in procvar declaration This procedure directive cannot be part of a procedural or function type declaration Error Function is already declared Public Forward arg1 You will get this error if a function is defined as forward twice Or if it occurs in the interface section and again as a forward declaration in the implementation section Error Can t use both EXPORT and EXTERNAL These two procedure directives are mutually exclusive Warning arg1 not yet supported inside inline procedure function Inline procedures don t sup port this declaration Warning Inlining disabled Inlining of procedures is disabled Info Writing Browser log arg1 When information messages are on the compiler warns you when it writes the browser log generated with the Y switch Hint may be pointer dereference is missing The compiler thinks that a pointer may need a deref erence Fatal
195. ou need to do something like that since those constructs were built for that Error Can t declare local variable as EXTERNAL Declaring local variables as external is not allowed Only global variables can reference external variables Error Procedure is already declared EXTERNAL The procedure is already declared with the EXTERNAL directive in an interface or forward declaration Warning Implicit uses of Variants unit The Variant type is used in the unit without any used unit using the Variants unit The compiler has implicitly added the Variants unit to the uses list To remove this warning the Variants unit needs to be added to the uses statement Error Class and static methods can t be used in INTERFACES The specifier class and direc tive static can t be used in interfaces because all methods of an interface must be public 144 APPENDIX C COMPILER MESSAGES Error Overflow in arithmetic operation An operation on two integer values produced an over flow Error Protected or private expected strict can be only used together with protected or private Error SLICE can t be used outside of parameter list s1ice can be used only for arguments ac cepting an open array parameter Error A DISPINTERFACE can t have a parent class A DISPINTERFACE is a special type of interface which can t have a parent class Error A DISPINTERFACE needs a guid A DISPINTERFACE always needs an interface identi fication a GUID Warning
196. output You can benefit from redirecting the output to a file because it could be quite a lot gprof yourexe gt profile log Hint you can use the f lat option to reduce the amount of output of gprof It will then only output the information about the timings For more information on the GNU profiler gpro f see its manual 10 5 Detecting heap memory leaks Free Pascal has a built in mechanism to detect memory leaks There is a plug in unit for the memory manager that analyses the memory allocation deallocation and prints a memory usage report after the program exits The unit that does this is called heaptrc If you want to use it you should include it as the first unit in your uses clause Alternatively you can supply the gh switch to the compiler and it will include the unit automatically for you After the program exits you will get a report looking like this Marked memory at 0040FA50 invalid Wrong size 128 allocated 64 freed 0x00408708 0x0040CB49 0x0040C481 Call trace for block 0x0040FA50 size 128 0x0040CB3D 0x0040C481 118 CHAPTER 10 DEBUGGING YOUR PROGRAMS The output of the heaptre unit is customizable by setting some variables Output can also be cus tomized using environment variables You can find more information about the usage of the heaptrc unit in the Unit reference 10 6 Line numbers in run time error backtraces Normally when a run time error occurs you are presented with a list of addres
197. packed in any mode with Sbitpacking on it will be packed at the bit level For performance reasons they cannot be used as loop variables Error VAR and TYPE are allowed only in generics The usage of VAR and TYPE to declare new types inside an object is allowed only inside generics Error This type can t be a generic Only Classes Objects Interfaces and Records are allowed to be used as generic Warning Don t load LINEINFO unit manually Use the gl compiler switch instead Do not use the lineinfo unit directly Use the g1 switch which automatically adds the correct unit for reading the selected type of debugging information The unit that needs to be used depends on the type of debug information used when compiling the binary Error No function result type specified for function arg1 The first time you declare a func tion you have to declare it completely including all parameters and the result type Error Specialization is only supported for generic types Types which are not generics can t be specialized 145 APPENDIX C COMPILER MESSAGES Error Generics can t be used as parameters when specializing generics When specializing a generic only non generic types can be used as parameters Error Constants of objects containing a VMT aren t allowed If an object requires a VMT ei ther because it contains a constructor or virtual methods it s not allowed to create constants of 1t In TP and Delphi mode this is allowe
198. pecific options when compiling some unit or program First we list the command line options and then we explain how to specify the command line options in the configuration file When reading this keep in mind that the options are case sensitive 5 1 Using the command line options The available options for the current version of the compiler are listed by category Also see chapter A page 121 for a listing as generated by the current compiler 5 1 1 General options h Print a list of all options and exit Same as h waiting after each screenfull for the enter key i Print copyright information You can supply a qualifier as ixxx where xxx can be one of the following D Returns the compiler date V Returns the compiler version SO Returns the compiler OS SP Returns the compiler processor TO Returns the target OS TP Returns the target processor l Print the Free Pascal logo and version number n Ignore the default configuration file You can still pass a configuration file with the option 23 CHAPTER 5 COMPILER CONFIGURATION 5 1 2 Options for getting feedback vxxx Be verbose xxx is a combination of the following Hoe Dp BD Sg H x oO oa 3B Aw CC amp K w Ya Show errors This option is on by default Display some general information Issue warnings Issue notes Issue hints Issue informational messages Report number of lines processed every 100 li
199. piling process or to debug the compiler s output This option can take an extra parameter mainly used for cross compilation It can have one of the following values h Generate script to link on host The generated script can be run on the compilation platform host platform t Generate script to link on target platform The generated script can be run on the target platform where the binary is intended to be run r Skip register allocation phase optimizations will be disabled Txxx Specify the target operating system xxx can be one of the following e emx OS 2 via EMX and DOS via EMX extender e freebsd FreeBSD e go32v2 DOS and version 2 of the DJ DELORIE extender e linux LINUX e netbsd NetBSD netware Novell Netware Module clib netwlibc Novell Netware Module libc openbsd OpenBSD 0s2 OS 2 2 x using the EMX extender e sunos SunOS Solaris e watcom Watcom compatible DOS extender e wdosx WDOSX extender e win32 WINDOWS 32 bit e wince WINDOWS for handhelds ARM processor UXXx Undefine the symbol xxx This is the opposite of the d option Ur Generate release unit files These files will not be recompiled even when the sources are avail able This is useful when making release distributions This also overrides the B option for release mode units W Set some WINDOWS or Os 2 attributes of the generated binary It can be one or more of the following Bhhh Set pref
200. platform after installing the compiler you may wish to set some environment variables The Free Pascal compiler recognizes the following variables e PPC_EXEC_PATH contains the directory where support files for the compiler can be found e PPC_CONFIG_PATH specifies an alternate path to find the fpc cfg e PPC_ERROR_FILE specifies the path and name of the error definition file e FPCDIR specifies the root directory of the Free Pascal installation e g C PP BIN 14 CHAPTER 2 INSTALLING THE COMPILER These locations are however set in the sample configuration file which is built at the end of the installation process except for the PPC_CONFIG_PATH variable which you must set if you didn t install things in the default places 2 4 Before compiling Also distributed in Free Pascal is a README file It contains the latest instructions for installing Free Pascal and should always be read first Furthermore platform specific information and common questions are addressed in the FAO It should be read before reporting any bug 2 5 Testing the compiler After the installation is completed and the optional environment variables are set as described above your first program can be compiled Included in the Free Pascal distribution are some demonstration programs showing what the com piler can do You can test if the compiler functions correctly by trying to compile these programs The compiler is ca
201. port C style operators i e x and Sd Try to be Delphi compatible Deprecated use Mdelphi instead SeN The compiler stops after the N th error Normally the compiler tries to continue compiling after an error until 50 errors are reached or a fatal error is reached and then it stops With this switch the compiler will stop after the N th error if N is omitted a default of 1 is assumed Instead of a number one of n h or w can also be specified In that case the compiler will consider notes hints or warnings as errors and stop when one is encountered Sg Support the label and goto commands By default these are not supported You must also specify this option if you use labels in assembler statements if you use the AT amp T style assember Sh Use ansistrings by default for strings If this option is specified the compiler will interpret the string keyword as an ansistring Otherwise it is supposed to be a shortstring TP style Si Support C style INLINE SIXXX Set interfaces style to XXX Sk Load the Kylix compatibility unit fpcylix Sm Support C style macros So Try to be Borland TP 7 0 compatible Deprecated use Mt p instead Sp Try to be gpc GNU Pascal compiler compatible Deprecated use Mgpc instead Ss The name of constructors must be init and the name of destructors should be done St Allow the static keyword in objects Sx Enable exception keywords default in Delphi Objfpc mode This wi
202. r changed to byte nsigned long int changed to cardinal u u e unsigned int changed to cardinal u u e unsigned short changed to word e void ignored These types are also changed if they appear in the arguments of a function or procedure functions and procedures Functions and procedures are translated as well Pointer types may be changed to call by reference arguments using the var argument by using the p command line argument Functions that have a variable number of arguments are changed to a function with a cvar modifier This used to be the array of const argument specifiers The extern specifier is recognized however it is ignored The packed specifier is also recognised and changed with the PACKRECORDS directive The const specifier is also recognized but is ignored modifiers If the w option is specified then the following modifiers are recognized STDCALL CDECL CALLBACK PASCAL WINAPI APIENTRY WINGDIAPI as defined in the win32 headers If additionally the x option is specified then the SYS_TRAP specifier is also recognized enums Enum constructs are changed into enumeration types Bear in mind that in C enumeration types can have values assigned to them Free Pascal also allows this to a certain degree If you know that values are assigned to enums it is best to use the e option to change the enumerations to a series of integer constants unions Unions are changed to variant
203. r in functionality to GNU autoconf or Imake for making X projects fpcmake accepts filenames of makefile description files as its command line arguments For each of these files it will create a Makefile in the same directory where the file is located overwriting any other existing file If no options are given it just attempts to read the file Makefile fpc in the current directory and tries to construct a makefile from it Any previously existing Makefile will be erased The format of the focmake configuration file is described in great detail in the appendices of the Programmers guide 8 3 fpdoc Pascal Unit documenter fpdoc is a program which generates fully cross referenced documentation for a unit It generates documentation for each identifier found in the unit s interface section The generated documentation can be in many formats for instance HTML RTF Text man page and LaTeX Unlike other docu mentation tools the documentation can be in a separate file in XML format so the sources aren t 100 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL cluttered with documentation Its companion program makeskel creates an empty XML file with entries for all identifiers or it can update an existing XML file adding entries for new identifiers fpdoc and makeskel are described in the FPDoc reference guide 8 4 h2pas C header to Pascal Unit converter h2pas attempts to convert a C header file to a Pascal unit it can handle
204. racts the file names and line numbers from the tool output is quite sophisti cated but in some cases it may fail 6 10 2 Grep One external tool in the Tools menu is already predefined a menu item to call the grep utility Tools Grep or SHIFT F2 Grep searches for a given string in files and returns the lines which contain the string The search string can even be a regular expression For this menu item to work the grep program must be installed since it is not distributed with Free Pascal The messages window displayed in figure 6 17 in the previous section shows the output of a typical grep session The messages window can be used in combination with grep to find special occur rences in the text Grep supports regular expressions A regular expression is a string with special characters which describe a whole class of expressions The command line in DOS or LINUX has limited support for regular expressions entering 1s pas or dir pas to get a list of all Pascal files in a directory pas is something similar to a regular expression It uses a wildcard to describe a whole class of strings those which end on pas Regular expressions offer much more for example A Z 0 9 describes all strings which begin with an upper case letter followed by one or more digits It is outside the scope of this manual to describe regular expressions in great detail Users of a LINUX system can get more information on grep using man grep o
205. red in the current t ype block Error Error in type definition There is an error in your definition of a new array type One of the range delimiters in an array declaration is erroneous For example Array 1 1 25 will trigger this error Error Forward type not resolved argl A symbol was forward defined but no declaration was encountered Error Only static variables can be used in static methods or outside methods A static method of an object can only access static variables Fatal record or class type expected The variable or expression isn t of the type recordorclass Error Instances of classes or objects with an abstract method are not allowed You are trying to generate an instance of a class which has an abstract method that wasn t overridden Warning Label not defined arg1 A label was declared but not defined Error Label used but not defined arg1 A label was declared and used but not defined Error Illegal label declaration This error should never happen it occurs if a label is defined out side a procedure or function Error GOTO and LABEL are not supported use switch Sg You must use the Sg switch to compile a program which has labels and goto statements By default label and goto aren t supported Error Label not found A goto label was encountered but the label wasn t declared Error identifier isn t a label The identifier specified after the goto isn t of type label Error label already d
206. resses e http www freepascal org is the main site It contains also useful mail addresses and links to other places It also contains the instructions for subscribing to the mailinglist CHAPTER 1 INTRODUCTION e http community freepascal org 10000 is a forum site where questions can be posted Other than that some mirrors exist Finally if you think something should be added to this manual entirely possible please do not hesitate and contact me at michael Ofreepascal org Let s get on with something useful Chapter 2 Installing the compiler 2 1 2 1 1 Before Installation Requirements Hardware requirements The compiler needs at least one of the following processors 1 4 5 6 An Intel 80386 or higher processor A coprocessor is not required although it will slow down your program s performance if you do floating point calculations without a coprocessor since emulation will be used An AMD64 or EMT64 processor A PowerPC processor A SPARC processor An ARM processor Older FPC versions exist for the motorola 68000 processor but these are no longer maintained Memory and disk requirements 1 2 3 8 Megabytes of free memory This is sufficient to allow compilation of small programs Large programs such as the compiler itself will require at least 64 MB of memory but 128MB is recommended Note that the compiled programs themselves do not need so much memory
207. rocedure The following example shows the problem 143 APPENDIX C COMPILER MESSAGES procedure pl label 11 procedure p2 begin goto 11 This goto ISN T allowed end begin p2 dle LE end Fatal Procedure too complex it requires too many registers Your procedure body is too long for the compiler You should split the procedure into multiple smaller procedures Error Illegal expression This can occur under many circumstances Usually when trying to eval uate constant expressions Error Invalid integer expression You made an expression which isn t an integer and the compiler expects the result to be an integer Error Illegal qualifier One of the following is happening e You re trying to access a field of a variable that is not a record e You re indexing a variable that is not an array e You re dereferencing a variable that is not a pointer Error High range limit lt low range limit You are declaring a subrange and the high limit is less than the low limit of the range Error Exit s parameter must be the name of the procedure it is used in Non local exit is not al lowed This error occurs only in mode MacPas Error Illegal assignment to for loop variable arg1 The type of a for loop variable must be an ordinal type Loop variables cannot be reals or strings You also cannot assign values to loop variables inside the loop Except in Delphi and TP modes Use a while or repeat loop instead if y
208. ror Illegal char constant This happens when you specify a character with its ASCII code as in 96 but the number is either illegal or out of range Fatal Can t open file arg1 Free Pascal cannot find the program or unit source file you specified on the command line Fatal Can t open include file arg1 Free Pascal cannot find the source file you specified in a Sinclude statement Error Illegal record alignment specifier arg1 You are specifying SPACKRECORDS n or SALIGN n with an illegal value for n For PACKRECORDS valid alignments are 1 2 4 8 16 32 C NORMAL DEFAULT and for ALIGN valid alignments are 1 2 4 8 16 32 ON OFF Under mode MacPas ALIGN also supports MAC68K POWER and RESET Error Illegal enum minimum size specifier argl You are specifying the SPACKENUM n with an illegal value for n Only 1 2 4 NORMAL or DEFAULT is valid here Error ENDIF expected for arg1 arg2 defined in arg3 line arg4 Your conditional compilation state ments are unbalanced Error Syntax error while parsing a conditional compiling expression There is an error in the expression following the Sif Sifc or setc compiler directives Error Evaluating a conditional compiling expression There is an error in the expression follow ing the Sif 1fcorsetc compiler directives Warning Macro contents are limited to 255 characters in length The contents of macros cannot be longer than 255 characters
209. rowser window can be closed with the usual com mands The behaviour of the browser can be customized with the browser options dialog using the Op tions Browser menu The browser options dialog looks like figure 6 9 The following options can be set in the browser options dialog Symbols Here the types of symbols displayed in the browser can be selected Labels Labels are shown Constants Constants are shown Types Types are shown Variables Variables are shown Procedures Procedures are shown Inherited Sub browsing Specifies what the browser should do when displaying the members of a complex symbol such as a record or class New browser The members are shown in a new browser window 53 CHAPTER 6 THE IDE Figure 6 9 The browser options dialog 29 eu row Preferred a ee ll nell Replace current The contents of the current window are replaced with the members of the selected complex symbol Preferred pane Specifies what pane is shown in the browser when it is initially opened Scope Reference Display Determines how the browser should display the symbols Qualified symbols Sort always Sorts the symbols in the browser window 6 8 Running programs A compiled program can be run straight from the IDE This can be done in one of several ways 1 select the Run Run menu or 2 press CTRL F9 If command line parameters should be passed to the program then these can be set through the Run Paramete
210. rs menu The program parameters dialog looks like figure 6 10 Figure 6 10 The program parameters dialog aS Once the program has started it will continue to run until 54 CHAPTER 6 THE IDE 1 the program quits normally 2 an error happens 3 a breakpoint is encountered or 4 the program is reset by the user The last alternative is only possible if the program is compiled with debug information Alternatively it is possible to position the cursor somewhere in a source file and run the program till the execution reaches the source line where the cursor is located This can be done by 1 selecting RunIGoto Cursor in the menu 2 pressing F4 Again this is only possible if the program was compiled with debug information The program can also executed line by line Pressing F8 will execute the next line of the program If the program wasn t started yet it is started Repeatedly pressing F8 will execute the program line by line and the IDE will show the line to be executed in an editor window If somewhere in the code a call occurs to a subroutine then pressing F8 will cause the whole routine to be executed before control returns to the IDE If the code of the subroutine should be stepped through as well then F7 should be used instead Using F7 will cause the IDE to execute line by line any subroutine that is encountered If a subroutine is being stepped through then the Run Until return menu will execu
211. s are used C 10 Command line handling errors This section lists errors that occur when the compiler is processing the command line or handling the configuration files Warning Only one source file supported You can specify only one source file on the command line The first one will be compiled others will be ignored This may indicate that you forgot a sign Warning DEF file can be created only for OS 2 This option can only be specified when you re compiling for OS 2 Error nested response files are not supported You can not nest response files with the file command line option Fatal No source file name in command line The compiler expects a source file name on the com mand line Note No option inside arg1 config file The compiler didn t find any option in that config file Error Illegal parameter argl You specified an unknown option 161 APPENDIX C COMPILER MESSAGES Hint writes help pages When an unknown option is given this message is diplayed Fatal Too many config files nested You can only nest up to 16 config files Fatal Unable to open file arg1 The option file cannot be found Reading further options from argl Displayed when you have notes turned on and the compiler switches to another options file Warning Target is already set to argl Displayed if more than one T option is specified Warning Shared libs not supported on DOS platform reverting to static If you specify CD for
212. s ce 64 cen eee Ne eee Eee E 100 8 4 h2pas C header to Pascal Unit converter o o 101 SAL OPS id 101 SAEZ COMIS ceco e a E e E Y 101 38 3 H2PAspp PEEPEDEESSOCTON h2pas coo sk a rr ee ee 103 CONTENTS Bol UGS A 103 S22 OPIORS op cole do ocho eee Oe ee RE ee 8 103 a ce ck Re a ee Go ale A Rae Ae algo ee 103 S ss a se ok he Ae EH Ee eee Oe 104 3 ptop Pascal source beautiier es c coes Sa ae eS eee eH Re Bed eek 105 8 3 1 pOppmeram o s sa cb eed tba a 105 882 The plop conheurationile ce ok bed eh Be SR OR a 106 pt POPUWME o 0 6 AS PMR SE Pee ook D Soe Balbo eo ee 107 89 PICON PORTA ds bb se ete eho ee Ber do Bw a 108 S 10 Wiican POST 6 ceo e a A A A Eee E 109 SIO1 Synopsis cc sree eona deed eb dbaee eben tea e ane es 109 S 102 De scriphon and SABE o oie oS Ook ee RE RR RS ES 109 8103 OpHORS s pood eh is a ee Pa ee 109 9 Units that come with Free Pascal 111 ST OTAN WMS ee ee ee a eRe Pad es 111 92 Warder DOS cocida se rs e BAR EHE ER SS Be we a 112 93 Under WINOWL gt ua Ha ee Eee ed ee Ee GS ee be Gees eS 112 9 4 Under Linux and BSD like platforms o o 113 OS Und OS ocio a a A A ee 113 96 Untarailabilir gt osos rre deeb cee eee RES eee ERE eS 114 10 Debugging your programs 115 10 1 Compiling your program with debugger support 115 10 2 Using gdb to debug your program 2 2 ee 116 10 3 Caveats when debugging wih gD i ecce
213. s the low er upper word dword of the argument Turbo Pascal always uses a 16 bit lo hi which always returns bits 0 7 for 1o and the bits 8 15 for hi If you want the Turbo Pascal behavior you have to type cast the argument to a word or integer Error Integer or real expression expected The first argument to str must be a real or integer type Error Wrong type arg1 in array constructor You are trying to use a type in an array construc tor which is not allowed Error Incompatible type for arg no arg1 Got arg2 expected arg3 You are trying to pass an invalid type for the specified parameter Error Method variable and Procedure variable are not compatible You can t assign a method to a procedure variable or a procedure to a method pointer Error Illegal constant passed to internal math function The constant argument passed to a 1n or sqrt function is out of the definition range of these functions Error Can t get the address of constants It is not possible to get the address of a constant be cause they aren t stored in memory you can try making it a typed constant Error Argument can t be assigned to Only expressions which can be on the left side of an as signment can be passed as call by reference arguments Remark Properties can be used on the left side of an assignment nevertheless they cannot be used as arguments Error Can t assign local procedure function to procedure variable It s not allowed t
214. scal 7 0 and Delphi 7 although this goal is not yet attained but it also enhances these languages with elements like operator overloading And unlike these ancestors it supports multiple platforms It also differs from them in the sense that you cannot use compiled units from one system for the other i e you cannot use TP compiled units Also there is a text version of an Integrated Development Environment IDE available for Free Pascal Users that prefer a graphical IDE can have a look at the Lazarus or MSIDE projects Free Pascal consists of several parts 1 The compiler program itself 2 The Run Time Library RTL 3 The packages This is a collection of many utility units ranging from the whole Windows 32 API through native ZIP BZIP file handling to the whole GTK 2 interface 4 The Free Class Library This is a set of class based utility units which give a database frame work image support web support XML support and many many more 5 Utility programs and units Of these you only need the first two in order to be able to use the compiler In this document we describe the use of the compiler and utilities The Pascal Language is described in the Reference guide and the available routines units are described in the RTL and FCL Unit reference guides 1 3 Getting more information If the documentation doesn t give an answer to your questions you can obtain more information on the Internet at the following add
215. se on a WINDOWS system it will be transformed to a backslash and vice versa This feature is controlled by 2 pre initialized variables in the system unit 98 CHAPTER 7 PORTING AND PORTABLE CODE AllowDirectorySeparators A set of characters which when used in filenames are treated as direc tory separators They are transformed to the DirectorySeparator character AllowDriveSeparators A set of characters which when used in filenames are treated as drive sep arator characters They are transformed to the DriveSeparator character 99 Chapter 8 Utilities that come with Free Pascal Besides the compiler and the runtime Library Free Pascal comes with some utility programs and units Here we list these programs and units 8 1 Demo programs and examples A suite of demonstration programs comes included with the Free Pascal distribution These programs have no other purpose than to demonstrate the capabilities of Free Pascal They are located in the demo directory of the sources All example programs mentioned in the documentation are available Check out the directories that are beneath the same directory as the demo directory The names of these directories end on ex There you will find all example sources 8 2 fpcmake fpcmake is the Free Pascal makefile constructor program It reads a Makefile fpc configuration file and converts it to a Makefile suitable for reading by GNU make to compile your projects It is simila
216. sed Comments All styles of comments in Free Pascal Reserved words All reserved words of Free Pascal See also Reference guide Strings Constant string expressions Numbers Numbers in decimal notation Hex numbers Numbers in hexadecimal notation Assembler Any assembler blocks Symbols Recognised symbols variables types Directives Compiler directives Tabs Tab characters in the source can be given a different color than other whitespace The editor uses some default settings but experimentation is the best way to find a suitable color scheme A good color scheme helps in detecting errors in sources since errors will result in wrong syntax highlighting 6 5 6 Code Completion Code completion means the editor will try to guess the text as it is being typed It does this by checking what text is typed and as soon as the typed text can be used to identify a keyword in a list of keywords the keyword will be presented in a small colored box under the typed text Pressing the ENTER key will complete the word in the text There is no code completion yet for filling in function arguments or choosing object methods as in e g the Lazarus or DelphiIDEs Code completion can be customized in the Code completion dialog reachable through the menu option Options Preferences Codecomple The list of keywords that can be completed can be maintained here The code completion dialog is shown in figure 6 5 The dialog shows in alphabet
217. ses that represent the call stack backtrace i e the addresses of all procedures that were invoked when the run time error occurred This list is not very informative so there exists a unit that generates the file names and line numbers of the called procedures using the addresses of the stack backtrace This unit is called lineinfo You can use this unit by giving the g1 option to the compiler The unit will be automatically included It is also possible to use the unit explicitly in your uses clause but you must make sure that you compile your program with debug info Here is an example program program testline procedure generateerror255 begin runerror 255 end procedure generateanerror begin generateerror255 end begin generateanerror end When compiled with g1 the following output is generated Runtime error 255 at 0x0040BDE5 0Ox0040BDE5 GENERATEERROR255 line 6 of testline pp 0Ox0040BDFO GENERATEANERROR line 13 of testline pp Ox0040BEO0C main line 17 of testline pp 0x0040B7B1 This is more understandable than the normal message Make sure that all units you use are compiled with debug info because if they are not no line number and filename can be found 10 7 Combining heaptrc and lineinfo If you combine the lineinfo and the heaptre information then the output of the heaptrc unit will contain the names of the files and line numbers of the procedures
218. sing Nasm nasmelf Elf32 LINUX file using Nasm nasmwin32 WINDOWS 32 bit file using Nasm nasmwdosx WINDOWS 32 bit DOSX file using Nasm nasmobj Object file using Nasm 25 CHAPTER 5 COMPILER CONFIGURATION masm Object file using Masm Microsoft tasm Object file using Tasm Borland elf Elf32 LINUX using internal writer coff Coff object file Go32v2 using the internal binary object writer pecoff PECoff object file Win32 using the internal binary object writer B Re compile all used units even if the unit sources didn t change since the last compilation b Generate browser info This information can be used by an Integrated Development Environment IDE to provide information on classes objects procedures types and variables in a unit bl The same as b but also generates information about local variables types and procedures Caxxx Set the ABI Application Binary Interface to xxx The i option gives the possible values for XXX Cb Generate big endian code Cc Set the default calling convention used by the compiler CD Create a dynamic library This is used to transform units into dynamically linkable libraries on LINUX Ce Emulate floating point operations Cfxxx Set the used floating point processor to XXX CFNN Set the minimal floating point precision to NN Possible values are 32 and 64 Cg Enable generation of PIC code This should only be necessary when generating librar
219. so contains a clock displaying the current time The menu is always available except when a dialog is opened If a dialog is opened it must be closed first in order to access the menu In certain windows a local menu is also available The local menu will appear where the cursor is and provides additional commands that are context sensitive 6 4 1 Accessing the menu The menu can be accessed in a number of ways 40 CHAPTER 6 THE IDE Figure 6 3 A typical dialog window Code eneration erbose rouser ssembler Syntax Switches Conditio al defines 1 By using the mouse to select items The mouse cursor should be located over the desired menu item and a left mouse click will then select it 2 By pressing F10 This will switch the IDE focus to the menu The arrow keys can then be used to navigate in the menu The ENTER key should be used to select items 3 To access menu items directly ALT lt HIGHLIGHTED MENU LETTER gt can be used to select a menu item Afterwards submenu entries can be selected by pressing the highlighted letter but without ALT E g ALT S G is a fast way to display the goto line dialog Every menu item is explained by a short text in the status bar When a local menu is available it can be accessed by pressing the right mouse button or ALT F10 To exit any menu without taking any action press the ESC key twice In the following all menu entries and their actions are described
220. solutions for this problem 1 Recompile all units manually with the g option 2 Specify the build option B when compiling with debugging support This will recompile all units and insert debugging information in each of the units 1A good reason not to include debug information in an executable you plan to distribute 115 CHAPTER 10 DEBUGGING YOUR PROGRAMS The second option may have undesirable side effects It may be that some units aren t found or compile incorrectly due to missing conditionals etc If all went well the executable now contains the necessary information with which you can debug it using GNU gdb 10 2 Using gdb to debug your program To use gdb to debug your program you can start the debugger and give it as an option the full name of your program gdb hello Or under DOS gdb hello exe This starts the debugger and the debugger immediately loads your program into memory but it does not run the program yet Instead you are presented with the following more or less message followed by the gdb prompt gdb GNU gdb 6 6 50 20070726 cvs Copyright C 2007 Free Software Foundation Inc GDB is free software covered by the GNU General Public License and you are welcome to change it and or distribute copies of it under certain conditions Type show copying to see the conditions There is absolutely no warranty for GDB Type show warranty for details This GDB was configured as x
221. source file was modified more recent than the unit file the compiler will attempt to recompile the unit with this source file If the compiler doesn t find a compiled version of the unit or when the B option is specified then the compiler will look in the same manner for the unit source file and attempt to recompile it It is recommended to set the unit search path in the configuration file fpc cfg If you do this you don t need to specify the unit search path on the command line every time you want to compile something 3 1 3 Include files If you include a file in your source with the I filename directive the compiler will look for it in the following places 1 It will look in the path specified in the include file name 2 It will look in the directory where the current source file is 3 it will look in all directories specified in the include file search path You can add files to the include file search path with the I see page 5 1 3 or F i see page 5 1 3 options As an example consider the following include statement in a file units foo pp i bar inc Then the following command fpc Iincfiles units foo pp will cause the compiler to look in the following directories for bar inc 1 The parent directory of the current directory 2 The units subdirectory of the current directory 3 The incfiles subdirectory of the current directory 3 1 4 Object files When you link to object files using the L
222. supports debug information for the GNU debugger gdb or its derivatives Insight on win32 or ddd on LINUX It can write 2 kinds of debug information stabs The old debug information format dwarf The new debug information format Both are understood by GDB This chapter briefly describes how to use this feature It doesn t attempt to describe completely the GNU debugger however For more information on the workings of the GNU debugger see the GDB User Manual Free Pascal also suports gprof the GNU profiler See section 10 4 for more information on profiling 10 1 Compiling your program with debugger support First of all you must be sure that the compiler is compiled with debugging support Unfortunately there is no way to check this at run time except by trying to compile a program with debugging support To compile a program with debugging support just specify the g option on the command line as follows fpc g hello pp This will incorporate debugging information in the executable generated from your program source You will notice that the size of the executable increases substantially because of this Note that the above will only incorporate debug information for the code that has been generated when compiling hello pp This means that if you used some units the system unit for instance which were not compiled with debugging support no debugging support will be available for the code in these units There are 2
223. symbol t Link static passes the static option to the linker X Link with smartlinked units defines the FPC_LINK_SMART symbol 5 1 5 Options concerning the sources language options For more information on these options see Programmers guide Mmode Set language mode to mode which can be one of the following delphi Try to be Delphi compatible This is more strict than the ob3fpc mode since some Free Pascal extensions are switched off fpc Free Pascal dialect default gpc Try to be gpc compatible macpas Try to be compatible with Macintosh Pascal dialects objfpe Switch on some Delphi extensions This is different from Delphi mode because some Free Pascal constructs are still available tp Try to be TP BP 7 0 compatible This means no function overloading etc Rxxx Specify what kind of assembler you use in your asm assembler code blocks Here xxx is one of the following 29 CHAPTER 5 COMPILER CONFIGURATION att asm blocks contain AT amp T style assembler This is the default style intel asm blocks contain Intel style assembler default Use the default assembler for the specified target direct asm blocks should be copied as is in the assembler only replacing certain variables S2 Switch on Delphi 2 extensions obj fpc mode Deprecated use Mob j fpc instead Sa Include assert statements in compiled code Omitting this option will cause assert statements to be ignored Sc Sup
224. t and will be linked in any program that uses it 20 CHAPTER 3 COMPILER USAGE 3 3 Compiling a unit Compiling a unit is not essentially different from compiling a program The difference is mainly that the linker isn t called in this case To compile a unit in the file foo pp just type fpc foo Recall the remark about file extensions in the previous section When all went well you will be left with 2 two unit files 1 foo ppu this is the file describing the unit you just compiled 2 foo o this file contains the actual code of the unit This file will eventually end up in the executables Both files are needed if you plan to use the unit for some programs So don t delete them If you want to distribute the unit you must provide both the ppu and o file One is useless without the other 3 4 Units libraries and smartlinking The Free Pascal compiler supports smartlinking and the creation of libraries However the default behaviour is to compile each unit into one big object file which will be linked as a whole into your program Shared libraries can be created on any platform except MS DOS It is also possible to take existing units and put them together in 1 static or shared library using the ppumove tool section 8 7 page 104 3 5 Reducing the size of your program When you created your program it is possible to reduce the size of the resulting executable This is possible because the compiler
225. t in Pascal is much easier than with C The compiler knows from the source which units sources etc 1t needs So the Free Pascal IDE does not need a full featured project manager like some C development environments offer Nevertheless there are some settings in the IDE which apply to projects 6 11 1 The primary file Without a primary file the IDE compiles runs the source of the active window when a program is started If a primary file is specified the IDE always compiles runs this source even if another source window is active With the menu item CompilelPrimary file a file dialog can be opened where the primary file can be selected Only the menu item CompilelCompile compiles the active window regardless This is useful if a large project is being edited and only the syntax of the current source should be checked The menu item CompilerlClear primary file restores the default behaviour of the IDE i e the compile and run commands apply to the active window 67 CHAPTER 6 THE IDE 6 11 2 The directory dialog In the directory dialog the directories can be specified where the compiler should look for units libraries object files It also says where the output files should be stored Multiple directories except for the output directory can be entered separated by semicolons The directories dialog is shown in figure 6 21 Figure 6 21 The directories configuration dialog I E bject directories ibrar
226. tches see the Program mers guide Back in argl When you use the vt switch the compiler tells you when it has finished reading an include file Warning Unsupported application type arg1 You get this warning if you specify an unknown application type with the directive SAPPTYPE Warning APPTYPE is not supported by the target OS The SAPPTYPE directive is supported by certain operating systems only Warning DESCRIPTION is not supported by the target OS The DESCRIPTION directive is not supported on this target OS Note VERSION is not supported by target OS The SVERSION directive is not supported on this target OS 129 APPENDIX C COMPILER MESSAGES Note VERSION only for exes or DLLs The SVERSION directive is only used for executable or DLL sources Warning Wrong format for VERSION directive arg1 The SVERSTON directive format is majorversion minorversion where majorversion and minorversion are words Error Illegal assembler style specified arg1 When you specify an assembler mode with the SASMMODE xxx directive the compiler didn t recognize the mode you specified Warning ASM reader switch is not possible inside asm statement arg1 will be effective only for next It is not possible to switch from one assembler reader to another inside an assembler block The new reader will be used for next assembler statements only Error Wrong switch toggle use ON OFF or You nee
227. te simple to operate ptop v 1 indent b bufsize c optsfile infile outfile The infile parameter is the Pascal file to be processed and will be written to outfile overwriting an existing outfile if it exists Some options modify the behaviour of ptop h Write an overview of the possible parameters and command line syntax c ptop cfg Read some configuration data from configuration file instead of using the internal de faults then A config file is not required the program can operate without one See also g i ident Set the number of indent spaces used for BEGIN END and other blocks b bufsize Set the streaming buffersize to bufsize The default is 255 0 is considered non valid and ignored v Be verbose Currently only outputs the number of lines read written and some error messages g ptop cfg Write ptop configuration defaults to the file ptop cfg The contents of this file can be changed to your liking and it can be used with the c option 105 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL 8 8 2 The ptop configuration file Creating and distributing a configuration file for ptop is not necessary unless you want to modify the standard behaviour of ptop The configuration file is never preloaded so if you want to use it you should always specify it with a c ptop cfg parameter The structure of a ptop configuration file is a simple building block repeated several 20 30 times for each Pascal key
228. te the program till the current subroutine ends If the program should be stopped before it quits by itself then this can be done by 1 selecting Run Program reset from the menu or 2 pressing CTRL F2 The running program will then be aborted 6 9 Debugging programs To debug a program it must be compiled with debug information Compiling a program with debug information allows you to 1 Execute the program line by line 2 Run the program up to a certain point a breakpoint 3 Inspect the contents of variables or memory locations while the program is running 6 9 1 Using breakpoints Breakpoints will cause a running program to stop when the execution reaches the line where the breakpoint was set At that moment control is returned to the IDE and it is possible to continue execution To set a breakpoint on the current source line use the DebuglBreakpoint menu entry or press CTRL F8 55 CHAPTER 6 THE IDE Figure 6 11 The breakpoint list window I Type i State i Position i Ignore i Conditions file line disabled thello pas i i A list of current breakpoints can be obtained through the DebuglBreakpoint list menu The breakpoint list window is shown in figure 6 11 In the breakpoint list window the following things can be done New Shows the breakpoint property dialog where the properties for a new breakpoint can be entered Edit Shows the breakpoint property dialog where the properties of th
229. tead to get an integer result When hints are on then an integer division with the operator will produce this message because the result will then be of type real Error string types doesn t match because of V mode When compiling in V mode the string you pass as a parameter should be of the exact same type as the declared parameter of the procedure Error succ or pred on enums with assignments not possible If you declare an enumeration type which has C like assignments in it such as in the following Tenum a b e 5 then you cannot use the Succ or Pred functions with this enumeration Error Can t read or write variables of this type You are trying to read or write a variable from or to a file of type text which doesn t support that variable s type Only integer types reals pchars and strings can be read from or written to a text file Booleans can only be written to text files 147 APPENDIX C COMPILER MESSAGES Error Can t use readIn or writeln on typed file readin and writeln are only allowed for text files Error Can t use read or write on untyped file read and write are only allowed for text or typed files Error Type conflict between set elements There is at least one set element which is of the wrong type i e not of the set type Warning lo hi dword qword returns the upper lower word dword Free Pascal supports an over loaded version of lo hi for longint dword int64 qword which return
230. ted text Text can be selected in 3 ways 1 Using the mouse dragging the mouse over existing text selects it 2 Using the keyboard press CTRL K B to mark the beginning of the selected text and CTRL K K to mark the end of the selected text 3 Using the keyboard hold the SHIFT key depressed while navigating with the cursor keys There are also some special select commands 1 The current line can be selected using CTRL K L 2 The current word can be selected using CTRL K T 47 Remark CHAPTER 6 THE IDE In the Free Pascal IDE selected text is persistent After selecting a range of text the cursor can be moved and the selection will not be destroyed hence the term block is more appropriate for the selection and will be used henceforth Several commands can be executed on a block Move the block to the cursor location CTRL K V Copy the block to the cursor location CTRL K C Delete the block CTRL K Y Write the block to a file CTRL K W e Read the contents of a file into a block CTRL K R If there is already a block this block is not replaced by this command The file is inserted at the current cursor position and then the inserted text is selected Indent a block CTRL K I Undent a block CTRL K U Print the block contents CTRL K P When searching and replacing the search can be restricted to the block contents 6 5 3 Setting bookmarks The IDE provides a feature whic
231. that occur in the stack backtrace In such a case the output will look something like this 119 CHAPTER 10 DEBUGGING YOUR PROGRAMS Marked memory at 00410DA0 invalid Wrong size 128 allocated 64 freed 0x004094B8 0x0040D8F9 main line 25 of heapex pp 0x0040D231 Call trace for block 0x00410DA0 size 128 0x0040D8ED main line 23 of heapex pp 0x0040D231 If lines without filename line number occur this means there is a unit which has no debug info included in the above case the getmem call itself 120 Appendix A Alphabetical listing of command line options The following is an alphabetical listing of all command line options as generated by the compiler Free Pascal Compiler version 2 3 1 2008 06 02 for x86_64 Copyright c 1993 2008 by Florian Klaempfl usr local lib fpc 2 3 1 ppcx64 options lt inputfile gt options Put after a boolean switch option to enable it to disable it za The compiler doesn t delete the generated assembler fil al List sourcecode lines in assembler file an List node info in assembler file ap Use pipes instead of creating temporary assembler files ar List register allocation release info in assembler file at List temp allocation release info in assembler file A lt x gt Output format Adefault Use default assembler Aas Assemble using GNU AS b Generate browser info bl Generate local symbol info B Build all modules
232. the DOS platform this message is displayed The compiler supports only static libraries under DOS Fatal too many IF N DEFs The IF N DEF statements in the options file are not balanced with the ENDIF statements Fatal too many ENDIFs The IF N DEF statements in the options file are not balanced with the ENDIF statements Fatal open conditional at the end of the file The IF N DEF statements in the options file are not balanced with the ENDIF statements Warning Debug information generation is not supported by this executable It is possible to have a compiler executable that doesn t support the generation of debugging info If you use such an executable with the g switch this warning will be displayed Hint Try recompiling with dGDB It is possible to have a compiler executable that doesn t sup port the generation of debugging info If you use such an executable with the g switch this warning will be displayed Warning You are using the obsolete switch arg1 This warns you when you use a switch that is not needed supported anymore It is recommended that you remove the switch to overcome problems in the future when the meaning of the switch may change Warning You are using the obsolete switch arg1 please use arg2 This warns you when you use a switch that is not supported anymore You must now use the second switch instead It is recommended that you change the switch to overcome problems in the
233. this module Globals Asks for the name of a global symbol and opens a browse window for this global symbol Symbol Opens a window with all known symbols so a symbol can be selected After the symbol is selected a browse window for that symbol is opened 6 4 5 The Run menu The Run menu contains all entries related to running a program Run CTRL F9 If the sources were modified compiles the program If the compile is successful the program is executed If the primary file was set then that is used to determine which program to execute See section 6 4 6 page 44 for more information on how to set the primary file Step over F8 Run the program until the next source line is reached If any calls to procedures are made these will be executed completely as well Trace into F7 Execute the current line If the current line contains a call to another procedure the process will stop at the entry point of the called procedure Goto cursor F4 Run the program until the execution point matches the line where the cursor is Until return Runs the current procedure until it exits Run directory Set the working directory to change to when executing the program Parameters Permits the entry of parameters that will be passed to the program when it is being executed Program reset CTRL F2 if the program is being run or debugged the debug session is aborted and the running program is killed 43 CHAPTER 6 THE IDE 6 4 6 The Comp
234. ting on the first column of a line IFDEF IFNDEF ELSE ENDIF DEFINE UNDEF WRITE INCLUDE SECTION They work the same way as their counterparts in Pascal source code All the default defines used to compile source code are also defined while processing the configuration file For example if the target compiler is an intel 80x86 compatible linux platform both cpu86 and linux will be defined while interpreting the configuration file For the possible default defines when compiling consult Appendix G of the Programmers guide What follows is a description of the different directives 5 2 1 IFDEF Syntax IFDEF name Lines following IFDEF are read only if the keyword name following it is defined They are read until the keywords ELSE or ENDIF are encountered after which normal processing is resumed Example 31 CHAPTER 5 COMPILER CONFIGURATION IFDEF VER2_2_0 Fu usr lib fpc 2 2 0 linuxunits ENDIF In the above example usr lib fpc 2 2 0 linuxunits will be added to the path if you re compiling with version 2 2 0 of the compiler 5 2 2 IFNDEF Syntax IFNDEF name Lines following IFNDEF are read only if the keyword name following it is not defined They are read until the keywords ELSE or ENDIF are encountered after which normal processing is resumed Example IFNDEF VER2_2_0 Fu usr lib fpc 2 2 0 linuxunits ENDIF
235. tive window CTRL F5 Switch to next window F6 Switch to last window SHIFT F6 Menu F10 Local menu ALT F10 List of windows ALT 0 Active another window ALT lt DIGIT gt Call grep utility SHIFT F2 Exit IDE ALT X 85 CHAPTER 6 THE IDE Ta ble 6 5 Compiler Command Shortcut key Alternative Reset debugger program CTRL F2 Display call stack CTRL F3 Run as far as the cursor F4 Switch to user screen ALT F5 Trace into F7 Add watch CTRL F7 Step over F8 Set breakpoint at current line CTRL F8 Make F9 Run CTRL F9 Compile the active source file ALT F9 Message F11 Compiler messages F12 Table 6 6 Text navigation Command Shortcut key Alternative Char left ARROW LEFT CTRL S Char right ARROW RIGHT CTRL D Line up ARROW UP CTRL E Line down ARROW DOWN CTRL X Word left CTRL ARROW LEFT CTRL A Word right CTRL ARROW RIGHT CTRL F Scroll one line up CTRL W Scroll one line down CTRL Z Page up PAGEUP CTRL R Page down PAGEDOWN Beginning of Line Pos CTRL Q S End of Line END CTRL Q D First line of window CTRL HOME CTRL Q E Last line of window CTRL END CTRL Q X First line of file CTRL PAGEUP CTRL Q R Last line of file CTRL PAGEDOWN CTRL Q C Last cursor position CTRL Q P Find matching block delimiter CTRL Q Find last matching block delimiter CTRL Q Table 6 7 Edit Command Shortcut key Alternative Delete char DEL CTRL G Delete left char BACKSPACE CTRL H Delete line CTRL Y Delete til end of line CTRL Q Y Delete word CTR
236. to this label so it will be focused when the user presses the highlighted letter in the label caption if any InputLine An edit field where a text can be entered CheckBox A checkbox which can be in an on or off state Origin Specifies where the control should be located in the dialog The origin is specified as left top and the top left corner of the dialog has coordinate 1 1 not counting the frame Size Specifies the size of the control which should be specified as Cols Rows Each control has some specific keywords associated with it they will be described below A label Type Labe1 has the following extra keywords associated with it Text the text displayed in the label If one of the letters should be highlighted so it can be used as a shortcut then it should be enclosed in tilde characters 7 E g in Text T ext to find the T will be highlighted Link The name of a control in the dialog may be specified If specified pressing the label s high lighted letter in combination with the ALT key will put the focus on the control specified here A label does not contribute to the text of the command line it is for informational and navigational purposes only The following is an example of a label description section label2 Type Label Origin 2 3 Size 22 1 Text File m ask Link filemask An edit control Type Input Line allows entry of arbitrary text The text of the edit control will be past
237. to type an expression Code templates can be added and edited in the code templates dialog reachable via the menu option Options Environment CodeTemplates The code templates dialog is shown in figure 6 6 The top listbox in the code templates dialog shows the names of all known templates The bottom half of the dialog shows the text associated with the currently highlighted code template The following buttons are available Ok Saves all changes and closes the dialog Edit Pops up a dialog that allows the editing of the currently highlighted code template Both the name and text can be edited New Pops up a dialog that allows the entry of a new code template which will be added to the list A name must be entered for the new template Delete Deletes the currently highlighted code template from the list Cancel Discards all changes and closes the dialog 50 Remark CHAPTER 6 THE IDE Figure 6 6 The code templates dialog i T ifthen All templates are saved and are available the next time the IDE is started Duplicates are not allowed If an attempt is made to add a duplicate name to the list an error will occur 6 6 Searching and replacing The IDE allows you to search for text in the active editor window To search for text one of the following can be done 1 Select SearchlFind in the menu 2 Press CTRL Q F After that the dialog shown in figure 6 7 will pop up and the following options
238. tool CAP_MSG Captures the output of the tool and puts it in the messages window CAP_EDIT Captures the output of the tool and puts it in a separate editor window COL Replaced by the column of the cursor in the active editor window If there is no active window or the active window is a dialog then it is replaced by 0 CONFIG Replaced by the complete filename of the current configuration file DIR Replaced by the full directory of the filename argument including the trailing directory separator e g 63 CHAPTER 6 THE IDE SDIR d data myfile pas would return d data DRIVE Replaced by the drive letter of the filename argument e g SDRIVE d data myfile pas would return d EDNAME Replaced by the complete file name of the file in the active edit window If there is no active edit window this is an empty string EXENAME Replaced by the executable name that would be created if the make command was used i e from the Primary File setting or the active edit window EXTO Replaced by the extension of the filename argument The extension includes the dot e g SEXT d data myfile pas would return pas LINE Replaced by the line number of the cursor in the active edit window If no edit window is P y present or active this is 0 NAME Replaced by the name part excluding extension and dot of the filename argument e g NAME d data myfile pas
239. u provides entry points to all the help functionality of the IDE as well as the means to customize the help system Contents Shows the help table of contents Index SHIFT F1 Jumps to the help Index Topic search CTRL F1 Jumps to the topic associated with the currently highlighted text Previous topic ALT F1 Jumps to the previously visited topic Using help Displays help on using the help system Files Allows the configuration of the help menu With this menu item help files can be added to the help system About Displays information about the IDE See section 6 13 3 page 84 for more information 6 5 Editing text In this section the basics of editing source text are explained The IDE works like many other text editors in this respect so mainly the distinguishing points of the IDE will be explained 6 5 1 Insert modes Normally the IDE is in insert mode This means that any text that is typed will be inserted before text that is present after the cursor In overwrite mode any text that is typed will replace existing text When in insert mode the cursor is a flat blinking line If the IDE is in overwrite mode the cursor is a cube with the height of one line Switching between insert mode and overwrite mode happens with the INSERT key or with the CTRL V key 6 5 2 Blocks The IDE handles selected text just as the Turbo Pascal IDE handles it This is slightly different from the way e g WINDOWS applications handle selec
240. u where it encounters conditional statements IFDEF argl found arg2 When you turn on conditional messages vc the compiler tells you where it encounters conditional statements IFOPT arg1 found arg2 When you turn on conditional messages vc the compiler tells you where it encounters conditional statements IF arg1 found arg2 When you turn on conditional messages vc the compiler tells you where it encounters conditional statements IFNDEF arg found arg2 When you turn on conditional messages vc the compiler tells you where it encounters conditional statements ELSE arg found arg2 When you turn on conditional messages vc the compiler tells you where it encounters conditional statements Skipping until When you turn on conditional messages vc the compiler tells you where it encounters conditional statements and whether it is skipping or compiling parts Info Press lt return gt to continue When the vi switch is used the compiler stops compilation and waits for the Enter key to be pressed when it encounters a STOP directive Warning Unsupported switch arg1 When warnings are turned on vw the compiler warns you about unsupported switches This means that the switch is used in Delphi or Turbo Pascal but not in Free Pascal Warning Illegal compiler directive arg1 When warnings are turned on vw the compiler warns you about unrecognised switches For a list of recognised swi
241. uplicate exported function index arg1 Exported function indexes inside a specific DLL must all be different Error Invalid index for exported function DLL function index must be in the range 1 SFFFF Warning Relocatable DLL or executable arg1 debug info does not work disabled It is currently not possible to include debug information in a relocatable DLL Warning To allow debugging for win32 code you need to disable relocation with WN option Stabs debug info is wrong for relocatable DLL or EXES Use WN if you want to debug win32 exe cutables Error Constructor name must be INIT You are declaring an object constructor with a name which is not init and the Ss switch is in effect See the switch Ss see page 5 1 5 Error Destructor name must be DONE You are declaring an object destructor with a name which is not done and the Ss switch is in effect See the switch Ss see page 5 1 5 Error Procedure type INLINE not supported You tried to compile a program with C style inlining and forgot to specify the Si option Si see page 5 1 5 The compiler doesn t support C styled inlining by default Warning Constructor should be public Constructors must be in the public part of an object class declaration Warning Destructor should be public Destructors must be in the public part of an object class declaration Note Class should have one destructor only You can declare only one destructor for a class
242. ut of such a program will be caught and displayed in the messages window Adding a tool to the tools menu can be done using the Options Tools menu This will display the tools dialog The tools dialog is shown in figure 6 20 In the tools dialog the following actions are available New Shows the tool properties dialog where the properties of a new tool can be entered Edit Shows the tool properties dialog where the properties of the highlighted tool can be edited Delete Removes the currently highlighted tool Cancel Discards all changes and closes the dialog 62 CHAPTER 6 THE IDE Table 6 3 Advanced calculator commands Operation Button Key Add the displayed number to the memory M Subtract the displayed number from the memory M Move the memory contents to the display M gt Move the display contents to the memory M lt Exchange display and memory contents M lt gt Figure 6 20 The tools configuration dialog OK Saves all changes and closes the dialog The definitions of the tools are written in the desktop configuration file So unless auto saving of the desktop file is enabled the desktop file should be saved explicitly after the dialog is closed 6 10 6 Meta parameters When specifying the command line for the called tool meta parameters can be used Meta parameters are variables and and they are replaced by their contents before passing the command line to the tool CAP Captures the output of the
243. vailable from the Free Software Foundation website 58 CHAPTER 6 THE IDE Figure 6 15 The call stack window hello pas 11 DOHELLO hello pas 15 main Figure 6 16 The GDB window GDB window 6 10 Using Tools The tools menu provides easy access to external tools It also has three pre defined tools for program mers an ASCII table a grep tool and a calculator The output of the external tools can be accessed through this menu as well 6 10 1 The messages window The output of the external utilities is redirected by the IDE and it will be displayed in the messages window The messages window is displayed automatically if an external tool was run The messages window can also be displayed manually by selecting the menu item Tools Messages or by pressing the F11 key The messages window is shown in figure 6 17 If the output of the tool contains filenames and line numbers the messages window can be used to navigate the source as in a browse window 1 Pressing ENTER or double clicking the output line will jump to the specified source line and close the messages window 59 CHAPTER 6 THE IDE Figure 6 17 The messages window 2 Pressing the space bar will jump to the specified source line but will leave the messages window open with the focus on it This allows the quick selection of another message line with the arrow keys and jump to another location in the sources The algorithm which ext
244. word known to the ptop program See the default configuration file or ptopu pp source to find out which keywords are known The basic building block of the configuration file consists of one or two lines describing how ptop should react on a certain keyword First comes a line without square brackets with the following format keyword option 1 option2 option3 If one of the options is dindonkey see further below a second line with square brackets is needed keyword otherkeyword1 otherkeyword2 otherkeyword3 As you can see the block contains two types of identifiers keywords keyword and otherkeyword1 3 in above example and options option1 3 above Keywords are the built in valid Pascal structure identifiers like BEGIN END CASE IF THEN ELSE IMPLEMENTATION The default configuration file lists most of these Besides the real Pascal keywords some other codewords are used for operators and comment expres sions as in table 8 1 Table 8 1 Keywords for operators Name of codeword Operator casevar in a case label unequal colon becomes delphicomment opencomment or closecomment or semicolon colon equals openparen closeparen period Ee ons The options codewords define actions to be taken when the keyword before the equal sign is found as listed in table 8 2 The option dindonkey given in table table 8 2 requires some further explanation dindonke
245. y is a contraction of DeINDent ON associated KEYword When it is present as an option in the first line then a second square bracketed line is required A de indent will be performed when any of the other keywords listed in the second line are encountered in the source Example The lines lse crbefore dindonkey inbytab upper else if then els mean the following 106 CHAPTER 8 UTILITIES THAT COME WITH FREE PASCAL Table 8 2 Possible options Option does what crsupp Suppress CR before the keyword crbefore Force CR before keyword do not use with crsupp blinbefore Blank line before keyword dindonkey De indent on associated keywords see below dindent Deindent always spbef Space before spaft Space after gobsym Print symbols which follow a keyword but which do not affect layout prints until terminators occur terminators are hard coded in pptop still needs changing inbytab Indent by tab crafter Force CR after keyword upper Prints keyword all uppercase lower Prints keyword all lowercase capital Capitalizes keyword 1st letter uppercase rest lowercase e The keyword this block is about is else because it s on the LEFT side of both equal signs e The option crbefore signals not to allow other code so just spaces before the ELSE key word on the same line e The option dindonkey de indents if the parser finds any of the keywords in the square brack ets line if then else
246. y directories nelude directories nit directories The following directories can be specified EXE amp PPU directories Specifies where the compiled units and executables will go FE see page 5 1 3 on the command line Object directories Specifies where the compiler looks for external object files Fo see page 5 1 3 on the command line Library directories Specifies where the compiler more exactly the linker looks for external li braries F 1 see page 5 1 3 on the command line Include directories Specifies where the compiler will look for include files included with the i directive F i see page 5 1 3 or I see page 5 1 3 on the command line Unit directories Specifies where the compiler will look for compiled units The compiler always looks first in the current directory and also in some standard directories Fu see page 5 1 3 on the command line 6 11 3 The target operating system The menu item CompilelTarget allows specification of the target operating system for which the sources will be compiled Changing the target doesn t affect any compiler switches or directories It does affect some defines defined by the compiler The settings here correspond to the option on the command line T see page 5 1 4 A sample compilation target dialog is shown in figure 6 22 the actual dialog will show only those targets that the IDE actually supports The following targets can be set the list
247. y reducing the number of terms Invalid numeric format in asm evaluator This fatal error is reported when a non numeric value is detected by the constant parser Normally this error should never occur Invalid Operator in asm evaluator This fatal error is reported when a mathematical operator is detected by the constant parser Normally this error should never occur Unknown error in asm evaluator This fatal error is reported when an internal error is detected by the constant parser Normally this error should never occur Invalid numeric value This warning is emitted when a conversion from octal binary or hexadeci mal to decimal is outside of the supported range Escape sequence ignored This error is emitted when a non ANSI C escape sequence is detected in aC string Asm syntax error Prefix not found This occurs when trying to use a non valid prefix instruction 163 APPENDIX C COMPILER MESSAGES Asm syntax error Trying to add more than one prefix This occurs when you try to add more than one prefix instruction Asm syntax error Opcode not found You have tried to use an unsupported or unknown opcode Constant value out of bounds This error is reported when the constant parser determines that the value you are using is out of bounds either with the opcode or with the constant declaration used Non label pattern contains This only applied to the m68k and Intel styled assembler This is reported when you try to use a no
248. y supported for Darwin Mac OS X Frameworks are not a known concept or at least not supported by FPC on operating systems other than Dar win Mac OS X Error Illegal minimal floating point constant precision arg1 Valid minimal precisions for float ing point constants are default 32 and 64 which mean respectively minimal usually 32 bit 32 bit and 64 bit precision Warning Overriding name of main procedure multiple times was previously set to argl The name for the main entry procedure is specified more than once Only the last name will be used 131 APPENDIX C COMPILER MESSAGES C 3 Parser messages This section lists all parser messages The parser takes care of the semantics of you language i e it determines if your Pascal constructs are correct Error Parser Syntax Error An error against the Turbo Pascal language was encountered This typically happens when an illegal character is found in the source file Error INTERRUPT procedure can t be nested An INTERRUPT procedure must be global Warning Procedure type argl ignored The specified procedure directive is ignored by FPC programs Error Not all declarations of arg1 are declared with OVERLOAD When you want to use over loading using the OVERLOAD directive then all declarations need to have OVERLOAD speci fied Error Duplicate exported function name arg1 Exported function names inside a specific DLL must all be different Error D

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