This appendix describes the possible defines when compiling programs using Free Pascal. A brief explanation of the define, and when it is used is also given.
| Define | description |
| FPC_LINK_DYNAMIC | Defined when the output will be linked dynamically. |
| This is defined when using the -XD compiler switch. | |
| FPC_LINK_STATIC | Defined when the output will be linked statically. |
| This is the default mode. | |
| FPC_LINK_SMART | Defined when the output will be smartlinked. |
| This is defined when using the -XX compiler switch. | |
| FPC_PROFILE | Defined when profiling code is added to program. |
| This is defined when using the -pg compiler switch. | |
| FPC_CROSSCOMPILING | Defined when the target OS/CPU |
| is different from the source OS/CPU. | |
| FPC | Always defined for Free Pascal. |
| VER2 | Always defined for Free Pascal version 2.x.x. |
| VER2_0 | Always defined for Free Pascal version 2.0.x. |
| VER2_2 | Always defined for Free Pascal version 2.2.x. |
| ENDIAN_LITTLE | Defined when the Free Pascal target is a little-endian processor |
| (80x86, Alpha, ARM). | |
| ENDIAN_BIG | Defined when the Free Pascal target is a big-endian processor |
| (680x0, PowerPC, SPARC, MIPS). | |
| FPC_DELPHI | Free Pascal is in Delphi mode, either using compiler switch -MDelphi or |
| using the $MODE DELPHI directive. | |
| FPC_OBJFPC | Free Pascal is in OBJFPC mode, either using compiler switch -Mobjfpc or |
| using the $MODE OBJFPC directive. | |
| FPC_TP | Free Pascal is in Turbo Pascal mode, either using compiler switch -Mtp or |
| using the $MODE TP directive. | |
| FPC_GPC | Free Pascal is in GNU Pascal mode, either using compiler switch -SP or |
| using the $MODE GPC directive. | |
Remark: The ENDIAN_LITTLE and ENDIAN_BIG defines were added starting from Free Pascal version 1.0.5.
| Define | When defined? |
| CPU86 | Free Pascal target is an Intel 80x86 or compatible. |
| CPU87 | Free Pascal target is an Intel 80x86 or compatible. |
| CPU386 | Free Pascal target is an Intel 80386 or later. |
| CPUI386 | Free Pascal target is an Intel 80386 or later. |
| CPU68K | Free Pascal target is a Motorola 680x0 or compatible. |
| CPUM68K | Free Pascal target is a Motorola 680x0 or compatible. |
| CPUM68020 | Free Pascal target is a Motorola 68020 or later. |
| CPU68 | Free Pascal target is a Motorola 680x0 or compatible. |
| CPUSPARC32 | Free Pascal target is a SPARC v7 or compatible. |
| CPUSPARC | Free Pascal target is a SPARC v7 or compatible. |
| CPUALPHA | Free Pascal target is an Alpha AXP or compatible. |
| CPUPOWERPC | Free Pascal target is a 32-bit or 64-bit PowerPC or compatible. |
| CPUPOWERPC32 | Free Pascal target is a 32-bit PowerPC or compatible. |
| CPUPOWERPC64 | Free Pascal target is a 64-bit PowerPC or compatible. |
| CPUX86_64 | Free Pascal target is a AMD64 or Intel 64-bit processor. |
| CPUAMD64 | Free Pascal target is a AMD64 or Intel 64-bit processor. |
| CPUIA64 | Free Pascal target is a Intel itanium 64-bit processor. |
| CPUARM | Free Pascal target is an ARM 32-bit processor. |
| CPUAVR | Free Pascal target is an AVR 16-bit processor. |
| CPU16 | Free Pascal target is a 16-bit CPU. |
| CPU32 | Free Pascal target is a 32-bit CPU. |
| CPU64 | Free Pascal target is a 64-bit CPU. |
| Define | When defined? |
| FPUSOFT | Software emulation of FPU (all types). |
| FPUSSE64 | SSE64 FPU on Intel I386 and higher, AMD64. |
| FPUSSE | SSE instructions on Intel I386 and higher. |
| FPUSSE2 | SSE 2 instructions on Intel I386 and higher. |
| FPUSSE3 | SSE 3 instructions on Intel I386 and higher, AMD64. |
| FPULIBGCC | GCC library FPU emulation on ARM and M68K. |
| FPU68881 | 68881 on M68K. |
| FPUFPA | FPA on ARM. |
| FPUFPA10 | FPA 10 on ARM. |
| FPUFPA11 | FPA 11 on ARM. |
| FPUVFP | VFP on ARM. |
| FPUX87 | X87 FPU on Intel I386 and higher. |
| FPUITANIUM | On Intel Itanium. |
| FPUSTANDARD | On PowerPC (32/64 bit). |
| FPUHARD | On Sparc. |
| Target operating system | Defines |
| linux | LINUX, UNIX |
| freebsd | FREEBSD, BSD, UNIX |
| netbsd | NETBSD, BSD, UNIX |
| sunos | SUNOS, SOLARIS, UNIX |
| go32v2 | GO32V2, DPMI |
| os2 | OS2 |
| emx | OS2, EMX |
| Windows (all) | WINDOWS |
| Windows 32-bit | WIN32, MSWINDOWS |
| Windows 64-bit | WIN64, MSWINDOWS |
| Windows (winCE) | WINCE, UNDER_CE, UNICODE |
| Classic Amiga | AMIGA |
| Atari TOS | ATARI |
| Classic Macintosh | MAC |
| PalmOS | PALMOS |
| BeOS | BEOS, UNIX |
| QNX RTP | QNX, UNIX |
| Mac OS X | BSD, DARWIN, UNIX |
Remark: The unix define was added starting from Free Pascal version 1.0.5. The BSD operating systems no longer define LINUX starting with version 1.0.7.