New macro GNUC_PREREQ for GCC version

* src/conf_post.h (GNUC_PREREQ): New macro.
Change uses of __GNUC_MINOR__ and __GNUC_PATCHLEVEL__ to use this
macro instead, for clarity and consistency.
(PRINTF_ARCHETYPE): New macro.  Define it to __gnu_printf__ only
if glibc, since non-GNU platforms don’t necessarily support GNU
printf formats.
(ATTRIBUTE_FORMAT_PRINTF): Use it.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/gmalloc.c b/src/gmalloc.c
index d795c13f616..483d05c5c61 100644
--- a/src/gmalloc.c
+++ b/src/gmalloc.c
@@ -44,7 +44,7 @@ License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 #endif
 
 #ifdef HAVE_MALLOC_H
-# if 4 < __GNUC__ + (2 <= __GNUC_MINOR__)
+# if GNUC_PREREQ (4, 2, 0)
 #  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 # endif
 # include <malloc.h>