diff --git a/libs/evoral/libsmf/smf.c b/libs/evoral/libsmf/smf.c
index 8697252d48..52fdba47ed 100644
--- a/libs/evoral/libsmf/smf.c
+++ b/libs/evoral/libsmf/smf.c
@@ -76,6 +76,8 @@ smf_new(void)
 	cantfail = smf_set_format(smf, 0);
 	assert(!cantfail);
 
+	(void) cantfail; /* keep gcc quiet */
+
 	smf_init_tempo(smf);
 
 	return (smf);
@@ -168,9 +170,7 @@ smf_track_delete(smf_track_t *track)
 void
 smf_add_track(smf_t *smf, smf_track_t *track)
 {
-#ifndef NDEBUG
 	int cantfail;
-#endif
 
 	assert(track->smf == NULL);
 
@@ -181,11 +181,11 @@ smf_add_track(smf_t *smf, smf_track_t *track)
 	track->track_number = smf->number_of_tracks;
 
 	if (smf->number_of_tracks > 1) {
-#ifndef NDEBUG
 		cantfail = smf_set_format(smf, 1);
+#ifndef NDEBUG
 		assert(!cantfail);
 #else
-		smf_set_format(smf, 1);
+		(void) cantfail;
 #endif
 
 	}