What predefined macro can I use to detect clang?

Question

I'm trying to detect the compiler used to compile my source code. I can easily find predefined macros to check for MSVC or GCC (see http://predef.sourceforge.net/ for example), but I cannot find any macro to check for clang.

Does someone know if clang defines a macro like __CLANG__ in order to know what is currently compiling my code ?

Answer 1

To get a list of all the predefined macros that the compiler uses, use this:

clang -dM -E -x c /dev/null

You can do the same for gcc.

Answer 2

Found the answer using strings + grep :

$ strings /usr/bin/clang | grep __ | grep -i clang
__clang__

Answer 3

This question has been answered for years but let me add (for future reference) how it is done in Windows:

echo | clang -dM -E -

same as for GCC:

echo | gcc -dM -E -

Please note: The last dash - is actually important! (Otherwise you get error: no input files for both compilers)