The Intel® C++ Compiler supports the predefined macros listed in the following table. The compiler also includes predefined macros specified by the ISO/ANSI standard. See Conformance to the C Standard.
| Macro Name | Value | Architecture |
|---|---|---|
| __BASE_FILE__ | Name of source file | Both |
| __cplusplus | 1 | Both |
| __EDG__ | 1 | Both |
| __EDG_VERSION__ | 303 | Both |
| __ELF__ | 1 | Both |
| __EXCEPTIONS | Defined when -fno-exceptions is not used. | IA-32 only |
| __GNUC__ | 2 - if gcc version is less than 3.2 3 - if gcc version is 3.2, 3.3, or 3.4 |
Both |
| __gnu_linux__ | 1 | Both |
| __GNUC_MINOR__ | 95 - if gcc version is less than 3.2 2 - if gcc version is 3.2 3 - if gcc version is 3.3 4 - if gcc version is 3.4 |
Both |
| __GNUC_PATCHLEVEL__ | 0 | Both |
| __GXX_ABI_VERSION | 102 | Both |
| __i386 | 1 | IA-32 only |
| __i386__ | 1 | IA-32 only |
| i386 | 1 | IA-32 only |
| __ia64 | 1 | Itanium architecture only |
| __ia64__ | 1 | Itanium architecture only |
| ia64 | 1 | Itanium architecture only |
| __INTEL_COMPILER | 810 | Both |
| __INTEL_COMPILER_BUILD_DATE | YYYYMMDD | Both |
| __INTEL_CXXLIB_ICC | 1 when -cxxlib_icc option is specified during compilation. | Both |
| __INTEL_RTTI__ | 1 when -fno-rtti is not specified. | Both |
| __INTEL_STRICT_ANSI__ | 1 when -strict_ansi is specified. | Both |
| _INTEGRAL_MAX_BITS | 64 | Itanium architecture only |
| __itanium__ | 1 | Itanium architecture only |
| __linux | 1 | Both |
| __linux__ | 1 | Both |
| linux | 1 | Both |
| __LONG_DOUBLE_SIZE__ | 80 | IA-32 only |
| __LONG_MAX__ | 9223372036854775807L | Itanium architecture only |
| __lp64 | 1 | Itanium architecture only |
| __LP64__ | 1 | Itanium architecture only |
| _LP64 | 1 | Itanium architecture only |
| __NO_INLINE__ | 1 | Both |
| __NO_MATH_INLINES | 1 | Both |
| __NO_STRING_INLINES | 1 | Both |
| __OPTIMIZE__ | 1 | Both |
| __PIC__ | 1 when -fPIC is used. | Both |
| __pic__ | 1 when -fPIC is used. | Both |
| _PGO_INSTRUMENT | 1 when -prof_gen[x] is used. | Both |
| __PTRDIFF_TYPE__ | int on IA-32 long on Itanium architecture |
Both |
| __REGISTER_PREFIX__ | (no value) | Both |
| __SIGNED_CHARS__ | 1 | Both |
| __SIZE_TYPE__ | unsigned on IA-32 unsigned long on Itanium architecture |
Both |
| __unix | 1 | Both |
| __unix__ | 1 | Both |
| unix | 1 | Both |
| __USER_LABEL_PREFIX__ | (no value) | Both |
| __VERSION__ | "Intel(R) C++ gcc 3.0 mode" | Both |
| __WCHAR_T | 1 | Both |
| __WCHAR_TYPE__ | long int on IA-32 int on Itanium architecture |
Both |
| __WINT_TYPE__ | unsigned int | Both |
Use the -Uname option to suppress any macro definition currently in effect for the specified name. The -U option performs the same function as an #undef preprocessor directive. You can use the -no-gcc option to disable the __GNUC_MINOR__, __GNUC_MINOR__, and __GNUC_PATCHLEVEL__ macros.