diff --git a/libc/include/signal.h b/libc/include/signal.h
index 9e5ce61..7bc3145 100644
--- a/libc/include/signal.h
+++ b/libc/include/signal.h
@@ -51,6 +51,7 @@
 #endif
 
 extern const char * const sys_siglist[];
+extern const char * const sys_signame[];
 
 static __inline__ int sigismember(sigset_t *set, int signum)
 {