diff --git a/src/include/tcsd.h b/src/include/tcsd.h
index 5b9462b..05bae97 100644
--- a/src/include/tcsd.h
+++ b/src/include/tcsd.h
@@ -166,8 +166,8 @@ void	   thread_signal_init();
 
 /* signal handling */
 #ifndef __APPLE__
-struct sigaction tcsd_sa_int;
-struct sigaction tcsd_sa_chld;
+extern struct sigaction tcsd_sa_int;
+extern struct sigaction tcsd_sa_chld;
 #endif
 
 #endif