Preprocessor Macro not working on Windows in Fortran Code

Question

Dear All I have a small Fortran program containing preprocessor macro. Below is a minimal example. On mac os x, it works well but when I compile it on windows 7 (64-bit) it

Answer 1

This might be GFortran PR 42954. Since GFortran started using libcpp instead of running cpp in a separate process, many of these built-in macros are missing.

As a workaround, you can as part of your build process generate a file with these builtin macro definitions which you can then include. E.g. have a make target which runs

gcc -E -dM - < /dev/null > builtins.inc

Then your sources should depend on builtins.inc in the Makefile, and in the beginning of your source files you

#include "builtins.inc"