Concatenating an expanded macro and a word using the Fortran preprocessor

Question

I\'m trying to concatenate a word in the source code with the expansion of a preprocessor macro. Basically I have foo somewhere in the code, and with a #d

Answer 1

I have done some research and it seems that basically most Fortran compilers (i.e. Intel and PGI) use a relatively normal C-preprocessor with a token pasting operator. We only need a special treatment for gfortran, which uses a C preprocessor in traditional mode without a token pasting operator.

Thanks to an entry on c-faq.com I found this definition of a CAT macro that works with all compilers I tested so far:

#ifdef __GFORTRAN__
#define PASTE(a) a
#define CAT(a,b) PASTE(a)b
#else
#define PASTE(a) a ## b
#define CAT(a,b) PASTE(a,b)
#endif

Another solution (that still uses the /**/ trick) was posted by Jonathan Leffler in this answer to a related question.