Fix block_all_signals compilation in 'strict ANSI' mode

* src/atomic_ops.c [(__linux__ || __GLIBC__ || __GNU__)
&& !AO_USE_NO_SIGNALS] (_GNU_SOURCE): Define (before including system
headers).

diff --git a/src/atomic_ops.c b/src/atomic_ops.c
index 5921c9b..a659621 100644 (file)
--- a/src/atomic_ops.c
+++ b/src/atomic_ops.c
@@ -43,6 +43,11 @@
 # define AO_USE_NO_SIGNALS
 #endif
 
+#if (defined(__linux__) || defined(__GLIBC__) || defined(__GNU__)) \
+    && !defined(AO_USE_NO_SIGNALS) && !defined(_GNU_SOURCE)
+# define _GNU_SOURCE 1
+#endif
+
 #undef AO_REQUIRE_CAS
 #include "atomic_ops.h" /* Without cas emulation! */