build: disable -Wmissing-braces on older compilers

GCC 4.9 and newer stopped warning for missing braces around the
"universal" C zero initializer {0}.  One such initializer sneaked
into scsi/qemu-pr-helper.c and is breaking the build with such
older GCC versions.

Detect the lack of support for the idiom, and disable the warning
in that case.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2017-10-20 12:11:32 +02:00
parent ab37bfc7d6
commit 20bc94a2b8

13
configure vendored
View File

@ -1669,6 +1669,19 @@ EOF
fi
fi
# Disable -Wmissing-braces on older compilers that warn even for
# the "universal" C zero initializer {0}.
cat > $TMPC << EOF
struct {
int a[2];
} x = {0};
EOF
if compile_object "-Werror" "" ; then
:
else
QEMU_CFLAGS="$QEMU_CFLAGS -Wno-missing-braces"
fi
# Workaround for http://gcc.gnu.org/PR55489. Happens with -fPIE/-fPIC and
# large functions that use global variables. The bug is in all releases of
# GCC, but it became particularly acute in 4.6.x and 4.7.x. It is fixed in