diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index f51942b..2bd058e 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -443,6 +443,12 @@
 /* Used to rename functions so that the compiler emits a call to 'x' rather than the function this was applied to. */
 #define __RENAME(x) __asm__(#x)
 
+#if __ANDROID_API__ < 21
+#define __BIONIC_LEGACY_INLINE static __inline
+#else
+#define __BIONIC_LEGACY_INLINE extern
+#endif
+
 #ifdef __clang__
 #define __AVAILABILITY(...) __attribute__((availability(android,__VA_ARGS__)))
 #define __INTRODUCED_IN(api_level) __AVAILABILITY(introduced=api_level)