Add C11's static_assert feature.


git-svn-id: svn+ssh://svn.code.sf.net/p/mingw-w64/code/trunk@5279 4407c894-4637-0410-b4f5-ada5f102cad1

mingw-w64-headers/crt/assert.h

diff --git a/mingw-w64-headers/crt/assert.h b/mingw-w64-headers/crt/assert.h
index f001c68..2fd4d9c 100644
--- a/mingw-w64-headers/crt/assert.h
+++ b/mingw-w64-headers/crt/assert.h
@@ -53,6 +53,14 @@
 
 #endif /* !defined (__ASSERT_H_) */
 
+#if (defined _ISOC11_SOURCE \
+     || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)) \
+    && !defined (__cplusplus)
+/* Static assertion.  Requires support in the compiler.  */
+#undef static_assert
+#define static_assert _Static_assert
+#endif
+
 #ifdef NDEBUG
 #define assert(_Expression) ((void)0)
 #else /* !defined (NDEBUG) */