diff --git a/jtag/src/part/part.c b/jtag/src/part/part.c
index 56e44169..a66a4876 100644
--- a/jtag/src/part/part.c
+++ b/jtag/src/part/part.c
@@ -151,12 +151,12 @@ part_get_signal( part *p, const char *pname )
 
 	if (!s) {
 		printf( "signal %s not found\n", pname );
-		return;
+		return -1;
 	}
 
 	if (!s->input) {
 		printf( "signal %s is not input signal\n", pname );
-		return;
+		return -1;
 	}
 
 	return p->prev_bsr->data[s->input->bit];