Commit bbbf2e04 authored by John Snow's avatar John Snow Committed by Stefan Hajnoczi
Browse files

configure: silence glib unknown attribute __alloc_size__ 

The glib headers use GCC attributes.  Unfortunately the __GNUC__ and
__GNUC_MINOR__ version macros are also defined by clang, but clang
doesn't support the same attributes as GCC.

clang 3.5.0 does not support the __alloc_size__ attribute:

  https://github.com/llvm-mirror/clang/commit/c047507a9a79e89fc8339e074fa72822a7e7ea73



The following warning is produced:

  gstrfuncs.h:257:44: warning: unknown attribute '__alloc_size__' ignored [-Wunknown-attributes]
        G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(2);
          gmacros.h:67:45: note: expanded from macro 'G_GNUC_ALLOC_SIZE'
                #define G_GNUC_ALLOC_SIZE(x) __attribute__((__alloc_size__(x)))

This patch checks whether glib headers cause warnings and disables
-Wunknown-attributes if it is able to.

Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarJohn Snow <jsnow@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427324259-1481-4-git-send-email-jsnow@redhat.com
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 93b25869

configure

+12 −0
Original line number Diff line number Diff line
@@ -2807,6 +2807,18 @@ if ! $pkg_config --atleast-version=2.38 glib-2.0; then 
    glib_subprocess=no

fi



# Silence clang 3.5.0 warnings about glib attribute __alloc_size__ usage

cat > $TMPC << EOF

#include <glib.h>

int main(void) { return 0; }

EOF

if ! compile_prog "$glib_cflags -Werror" "$glib_libs" ; then

    if cc_has_warning_flag "-Wno-unknown-attributes"; then

        glib_cflags="-Wno-unknown-attributes $glib_cflags"

        CFLAGS="-Wno-unknown-attributes $CFLAGS"

    fi

fi



##########################################

# SHA command probe for modules

if test "$modules" = yes; then