Syntax:
The /define option defines the symbol specified for use with conditional compilation directives or the Fortran preprocessor, FPP. A value specified for /define can be a character or integer value. If a value is not specified, 1 is assigned to symbol.
When only using the Fortran preprocessor FPP, to request that symbol values defined by /define apply only to FPP and are not seen by compiler directives, also specify /nodefine on the DF command line.
In the visual development environment, specify the Predefined Preprocessor Symbols in the General or Preprocessor Compiler Option Category.
You can use the directives to detect symbol definitions, such as the IF Directive Construct. Like certain other compiler options, an equivalent directive exists (DEFINE directive).
The following preprocessor symbols are predefined by the compiler system and are available to compiler directives and FPP (except _DF_VERSION_ and _VF_VERSION_):
Predefined Preprocessor Symbols
| Predefined Symbol Name and Value | Conditions When this Symbol is Defined |
|---|---|
| _DF_VERSION_=660 (660 for Version 6.6) | Compiler only |
| _DLL=1 | Only if /libs:dll, /MDs, /MD, /dll, or /LD is specified, but not when /libs:static is specified |
| _INTEGRAL_MAX_BITS=32 | Only for ia32 (32-bit) systems |
| _INTEGRAL_MAX_BITS=64 | Only for ia64 (64-bit) systems |
| _ITANIUM_A3_=1 | Only for ia64 (64-bit) systems |
| _MSFORTRAN_=401 | Only if /fpscomp:symbols is specified or you use the FL32 command |
| _MT=1 | Only if /threads or /MT is specified |
| _M_IX86=500 | Only for ia32 (32-bit) systems |
| _M_IA64=64100 | Only for ia64 (64-bit) systems |
| _VF_VERSION_=660 (660 for Version 6.6) | Compiler only |
| _WIN32=1 | Always defined (both ia32 and ia64 systems) |
| _WIN64=1 | Only for ia64 (64-bit) systems |
| _WIN95=1 | Only for ia32 (32-bit) systems running the Windows 95 operating system |
| _WIN98=1 | Only for ia32 (32-bit) systems running the Windows 98 operating system |
| _WINME=1 | Only for ia32 (32-bit) systems running the Windows Me operating system |
| _X86_=1 | Only for ia32 (32-bit) systems |
When using the non-native ia64 compiler, platform-specific symbols are set for the target platform of the executable, not for the system in use.