Index: sys/sys/cdefs.h
===================================================================
--- sys/sys/cdefs.h
+++ sys/sys/cdefs.h
@@ -96,16 +96,12 @@
 #define	__GNUCLIKE_BUILTIN_VAALIST 1
 #endif
 
-#if defined(__GNUC__)
 #define	__GNUC_VA_LIST_COMPATIBILITY 1
-#endif
 
 /*
  * Compiler memory barriers, specific to gcc and clang.
  */
-#if defined(__GNUC__)
 #define	__compiler_membar()	__asm __volatile(" " : : : "memory")
-#endif
 
 #define	__GNUCLIKE_BUILTIN_NEXT_ARG 1
 #define	__GNUCLIKE_MATH_BUILTIN_RELOPS