[glib/nirbheek/static-assert-c11] gmacros: Use _Static_assert when C11 is available

[Nirbheek Chauhan <nirbheekc src gnome org>]

commit 5d14764a6bcfc970e740a3d83b4a9eb06de5077e
Author: Nirbheek Chauhan <nirbheek centricular com>
Date:   Thu Jun 27 13:37:58 2019 +0530

    gmacros: Use _Static_assert when C11 is available
    
    The static assert message is much nicer to read, and is less likely to
    be misinterpreted as a false positive.
    
    glib is built with `-std=gnu89`, but this macro will be available to
    projects that use glib with c11 or gnu11.

 glib/gmacros.h | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)
---
diff --git a/glib/gmacros.h b/glib/gmacros.h
index 1c8d64699..c101da6cd 100644
--- a/glib/gmacros.h
+++ b/glib/gmacros.h
@@ -734,13 +734,21 @@
 #ifndef __GI_SCANNER__ /* The static assert macro really confuses the introspection parser */
 #define G_PASTE_ARGS(identifier1,identifier2) identifier1 ## identifier2
 #define G_PASTE(identifier1,identifier2)      G_PASTE_ARGS (identifier1, identifier2)
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
+#define G_STATIC_ASSERT(expr) _Static_assert (expr, "Expression evaluates to false")
+#define G_STATIC_ASSERT_EXPR(expr) _Static_assert (expr, "Expression evaluates to false")
+#elif defined(__cplusplus) && __cplusplus >= 201103L
+#define G_STATIC_ASSERT(expr) static_assert (expr, "Expression evaluates to false")
+#define G_STATIC_ASSERT_EXPR(expr) static_assert (expr, "Expression evaluates to false")
+#else
 #ifdef __COUNTER__
 #define G_STATIC_ASSERT(expr) typedef char G_PASTE (_GStaticAssertCompileTimeAssertion_, __COUNTER__)[(expr) 
? 1 : -1] G_GNUC_UNUSED
 #else
 #define G_STATIC_ASSERT(expr) typedef char G_PASTE (_GStaticAssertCompileTimeAssertion_, __LINE__)[(expr) ? 
1 : -1] G_GNUC_UNUSED
 #endif
 #define G_STATIC_ASSERT_EXPR(expr) ((void) sizeof (char[(expr) ? 1 : -1]))
-#endif
+#endif /* __STDC_VERSION__ */
+#endif /* !__GI_SCANNER__ */
 
 /* Provide a string identifying the current code position */
 #if defined(__GNUC__) && (__GNUC__ < 3) && !defined(__cplusplus)