llvm/autoconf/m4/cxx_flag_check.m4
Richard Smith d31bd24b40 configure: when performing a compiler feature test for a -Wno-foo flag, attempt
to use -Wfoo instead of -Wno-foo. This works around a bug in some versions of
gcc, where it will silently accept an unknown -Wno-foo option, but will
generate an error for a compile which uses -Wno-foo if that compile also
triggers any warnings.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174770 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-08 22:55:10 +00:00

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AC_DEFUN([CXX_FLAG_CHECK],
[AC_SUBST($1, `$CXX -Werror patsubst($2, [^-Wno-], [-W]) -fsyntax-only -xc /dev/null 2>/dev/null && echo $2`)])