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| author | Erik de Castro Lopo <erikd@mega-nerd.com> | 2013-11-22 18:13:36 +1100 |
|---|---|---|
| committer | Erik de Castro Lopo <erikd@mega-nerd.com> | 2013-11-22 18:13:40 +1100 |
| commit | a6a4b6f2052829c205319ecb0f5df553baedc9a4 (patch) | |
| tree | 2f97b1c5f9b2bcc72e7eb1187fbda801eef8d93a /m4 | |
| parent | 8e2eea6322348de674ebb4d3a2295131c92b0c49 (diff) | |
| download | flac-a6a4b6f2052829c205319ecb0f5df553baedc9a4.tar.gz | |
Detect Clang masquerading as GCC.
Autoconf detects the Clang compiler as GNU GCC (clang sets defines like
__GNUC__ etc) but Clang is *not* completely compatible. If we detect
Clang we set ac_vc_c_compiler_gnu to 'no'.
Diffstat (limited to 'm4')
| -rw-r--r-- | m4/clang.m4 | 31 | ||||
| -rw-r--r-- | m4/really_gcc.m4 | 32 |
2 files changed, 63 insertions, 0 deletions
diff --git a/m4/clang.m4 b/m4/clang.m4 new file mode 100644 index 00000000..036f0e68 --- /dev/null +++ b/m4/clang.m4 @@ -0,0 +1,31 @@ +dnl @synopsis XIPH_C_COMPILER_IS_CLANG +dnl +dnl Find out if a compiler claiming to be gcc really is gcc (clang lies). +dnl @version 1.0 Oct 31 2013 +dnl @author Erik de Castro Lopo <erikd AT mega-nerd DOT com> +dnl +dnl Permission to use, copy, modify, distribute, and sell this file for any +dnl purpose is hereby granted without fee, provided that the above copyright +dnl and this permission notice appear in all copies. No representations are +dnl made about the suitability of this software for any purpose. It is +dnl provided "as is" without express or implied warranty. +dnl + + +AC_DEFUN([XIPH_C_COMPILER_IS_CLANG], +[AC_CACHE_CHECK(whether we are using the CLANG C compiler, + xiph_cv_c_compiler_clang, + [ AC_LANG_ASSERT(C) + AC_TRY_LINK([ + #include <stdio.h> + ], + [ + #ifndef __clang__ + This is not clang! + #endif + ], + xiph_cv_c_compiler_clang=yes, + xiph_cv_c_compiler_clang=no + ]) + )] +) diff --git a/m4/really_gcc.m4 b/m4/really_gcc.m4 new file mode 100644 index 00000000..cba53ab3 --- /dev/null +++ b/m4/really_gcc.m4 @@ -0,0 +1,32 @@ +dnl @synopsis XIPH_GCC_REALLY_IS_GCC +dnl +dnl Find out if a compiler claiming to be gcc really is gcc (clang lies). +dnl @version 1.0 Oct 31 2013 +dnl @author Erik de Castro Lopo <erikd AT mega-nerd DOT com> +dnl +dnl Permission to use, copy, modify, distribute, and sell this file for any +dnl purpose is hereby granted without fee, provided that the above copyright +dnl and this permission notice appear in all copies. No representations are +dnl made about the suitability of this software for any purpose. It is +dnl provided "as is" without express or implied warranty. +dnl + +# If the configure script has already detected GNU GCC, then make sure it +# isn't CLANG masquerading as GCC. + +AC_DEFUN([XIPH_GCC_REALLY_IS_GCC], +[ AC_LANG_ASSERT(C) + if test "x$ac_cv_c_compiler_gnu" = "xyes" ; then + AC_TRY_LINK([ + #include <stdio.h> + ], + [ + #ifdef __clang__ + This is clang! + #endif + ], + ac_cv_c_compiler_gnu=yes, + ac_cv_c_compiler_gnu=no + ) + fi +]) |