3.7.2. Common Predefined Macros
3.7.2 Common Predefined Macros
The common predefined macros are GNU C extensions. They are available with the same meanings regardless of the machine or operating system on which you are using GNU C or GNU Fortran. Their names all start with double underscores.
__COUNTER__
- This macro expands to sequential integral values starting from 0. In conjunction with the
##
operator, this provides a convenient means to generate unique identifiers. Care must be taken to ensure that__COUNTER__
is not expanded prior to inclusion of precompiled headers which use it. Otherwise, the precompiled headers will not be used. __GFORTRAN__
- The GNU Fortran compiler defines this.
-
__GNUC__
__GNUC_MINOR__
__GNUC_PATCHLEVEL__
- These macros are defined by all GNU compilers that use th