Fix warnings in test-powerpc-snan.c

ChangeLog

@@ -1,5 +1,10 @@
 2013-01-04  Andreas Schwab  <schwab@linux-m68k.org>
 
+	* sysdeps/powerpc/fpu/test-powerpc-snan.c (_GNU_SOURCE): Define as
+	1 to avoid redefinition warning.
+	(__USE_GNU): Don't define.
+	(init_signaling_nan): Protoize.
+
 	* sysdeps/powerpc/fpu/libm-test-ulps: Update.
 
 2013-01-04  Siddhesh Poyarekar  <siddhesh@redhat.com>

sysdeps/powerpc/fpu/test-powerpc-snan.c

@@ -17,8 +17,7 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#define _GNU_SOURCE
-#define __USE_GNU
+#define _GNU_SOURCE 1
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/time.h>
@@ -42,7 +41,7 @@ long double SNANl;
 static sigjmp_buf sigfpe_buf;
 
 void
-init_signaling_nan()
+init_signaling_nan (void)
 {
     union {
 	double _ld16;