configure.ac: Add AC_USE_SYSTEM_EXTENSIONS.

* configure.ac: Add AC_USE_SYSTEM_EXTENSIONS.
	* mmapio.c: Don't define _GNU_SOURCE.
	* configure, config.h.in: Rebuild.

From-SVN: r191435

libbacktrace/ChangeLog

@@ -1,3 +1,9 @@
+2012-09-18  Ian Lance Taylor  <iant@google.com>
+
+	* configure.ac: Add AC_USE_SYSTEM_EXTENSIONS.
+	* mmapio.c: Don't define _GNU_SOURCE.
+	* configure, config.h.in: Rebuild.
+
 2012-09-18  Ian Lance Taylor  <iant@google.com>
 
 	* configure.ac: Check whether strnlen is declared.

libbacktrace/config.h.in

@@ -70,3 +70,35 @@
 
 /* Define to 1 if you have the ANSI C header files. */
 #undef STDC_HEADERS
+
+/* Enable extensions on AIX 3, Interix.  */
+#ifndef _ALL_SOURCE
+# undef _ALL_SOURCE
+#endif
+/* Enable GNU extensions on systems that have them.  */
+#ifndef _GNU_SOURCE
+# undef _GNU_SOURCE
+#endif
+/* Enable threading extensions on Solaris.  */
+#ifndef _POSIX_PTHREAD_SEMANTICS
+# undef _POSIX_PTHREAD_SEMANTICS
+#endif
+/* Enable extensions on HP NonStop.  */
+#ifndef _TANDEM_SOURCE
+# undef _TANDEM_SOURCE
+#endif
+/* Enable general extensions on Solaris.  */
+#ifndef __EXTENSIONS__
+# undef __EXTENSIONS__
+#endif
+
+
+/* Define to 1 if on MINIX. */
+#undef _MINIX
+
+/* Define to 2 if the system does not provide POSIX.1 features except with
+   this defined. */
+#undef _POSIX_1_SOURCE
+
+/* Define to 1 if you need to in order for `stat' and other things to work. */
+#undef _POSIX_SOURCE

libbacktrace/configure.ac

@@ -37,6 +37,8 @@ AC_CONFIG_HEADER(config.h)
 AC_CANONICAL_SYSTEM
 target_alias=${target_alias-$host_alias}
 
+AC_USE_SYSTEM_EXTENSIONS
+
 libtool_VERSION=1:0:0
 AC_SUBST(libtool_VERSION)
 

libbacktrace/mmapio.c

@@ -30,8 +30,6 @@ STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 POSSIBILITY OF SUCH DAMAGE.  */
 
-#define _GNU_SOURCE
-
 #include "config.h"
 
 #include <errno.h>