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 ?

[Updated list of compiler macros](http://sourceforge.net/p/predef/wiki/Compilers/) — chrisaycock, Nov 30 '12 at 16:54

score 128 · Answer 1 · edited Jul 19 '17 at 17:00

128

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.

edited Jul 19 '17 at 17:00

Martijn Courteaux

65,802
45
192
282

answered Apr 29 '11 at 04:00

Chris Suter

2,837
2
18
10

score 84 · Accepted Answer · answered Apr 17 '10 at 13:23

84

Found the answer using strings + grep :

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

answered Apr 17 '10 at 13:23

Pierre Bourdon

9,974
4
32
27

score 44 · Answer 3 · answered Jul 27 '12 at 10:37

44

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)

answered Jul 27 '12 at 10:37

Bernd Elkemann

22,963
4
39
63

8

FYI, Windows equivalent of `/dev/null` is `NUL:` – legalize Nov 06 '13 at 21:38
@legalize Whoa! I didn't know that! That's pretty cool; where'd you find that? – MD XF Mar 08 '17 at 17:09
4

It's been there since the DOS days, just most DOS/Windows users never needed it. – legalize Mar 08 '17 at 18:49
This is what I usually do in Linux as well. Typing `/dev/null` is more work. – Peter Cordes Jul 09 '17 at 10:49

What predefined macro can I use to detect clang?

3 Answers3

Linked