diff --git a/tools/regression/filemon/timed-forkb.c b/tools/regression/filemon/timed-forkb.c
index a7df9998dc8e..f7d66730abfd 100644
--- a/tools/regression/filemon/timed-forkb.c
+++ b/tools/regression/filemon/timed-forkb.c
@@ -45,6 +45,7 @@
 #define	SLEEP	20	/* seconds */
 #endif
 
+extern int verbose;
 int verbose;
 
 static void