diff --git a/libc/include/ctype.h b/libc/include/ctype.h
index b5f9ff4..58b76ea 100644
--- a/libc/include/ctype.h
+++ b/libc/include/ctype.h
@@ -59,7 +59,11 @@
 
 /* extern __inline is a GNU C extension */
 #ifdef __GNUC__
+#  if defined(__GNUC_STDC_INLINE__)
+#define	__CTYPE_INLINE	extern __inline __attribute__((__gnu_inline__))
+#  else
 #define	__CTYPE_INLINE	extern __inline
+#  endif
 #else
 #define	__CTYPE_INLINE	static __inline
 #endif