debug: use c99 standard instead of gcc extensions

Signed-off-by: Axel Heider <axelheider@gmx.de>

include/assert.h

@@ -30,7 +30,7 @@ void _assert_fail(
 #define assert(expr) \
     do { \
         if (!(expr)) { \
-            _assert_fail(#expr, __FILE__, __LINE__, __FUNCTION__); \
+            _assert_fail(#expr, __FILE__, __LINE__, __func__); \
         } \
     } while(0)
 

libsel4/include/sel4/assert.h

@@ -32,7 +32,7 @@ void __assert_fail(const char  *str, const char *file, int line, const char *fun
  * expr as a string plus the file, line and function.
  */
 #define seL4_Assert(expr) \
-    do { if (!(expr)) { __assert_fail(#expr, __FILE__, __LINE__, __FUNCTION__); } } while(0)
+    do { if (!(expr)) { __assert_fail(#expr, __FILE__, __LINE__, __func__); } } while(0)
 
 /**
  * An assert that tests that the expr is a compile time constant and