diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index 3617aba..1976d6a 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -516,13 +516,14 @@
 #include <android/api-level.h>
 
 #if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && defined(__OPTIMIZE__) && __OPTIMIZE__ > 0 && !defined(__clang__)
+#define __BIONIC_FORTIFY 1
 #define __BIONIC_FORTIFY_INLINE \
     extern inline \
     __attribute__ ((always_inline)) \
     __attribute__ ((gnu_inline)) \
     __attribute__ ((artificial))
-#define __BIONIC_FORTIFY_UNKNOWN_SIZE ((size_t) -1)
 #endif
+#define __BIONIC_FORTIFY_UNKNOWN_SIZE ((size_t) -1)
 
 /* Android-added: for FreeBSD's libm. */
 #define __weak_reference(sym,alias) \