Mesa already defines _GNU_SOURCE for glibc based systems and defining
_GNU_SOURCE will break the Mesa build on other systems such as OpenBSD.
_GNU_SOURCE only seems to be included in llvm-config output when
LLVM is built via autoconf and not when it is built by cmake.
Cc: "10.2 10.3" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Jonathan Gray <jsg@jsg.id.au>
# Use \> (marks the end of the word)
echo `$1` | sed \
-e 's/-DNDEBUG\>//g' \
+ -e 's/-D_GNU_SOURCE\>//g' \
-e 's/-pedantic\>//g' \
-e 's/-Wcovered-switch-default\>//g' \
-e 's/-O.\>//g' \