I'm guessing you've seen a bunch of ugly macros to detect the compiler on which the code is compiled. Something like this is a typical practice in C word:
#include <something_that_defines_macros>
#if !defined(__clang__) \
&& !defined(__ICC) \
&& !defined(__INTEL_COMPILER) \
&& (defined(__GNUC__) || defined(__GNUG__))
// GCC specific
#endif
Now, try to come up with a good macro to detect the GCC compiler. Try to make that macro usage as short as possible.
Take a look at the following recipe to verify your guess.