diff --git a/conf.c b/conf.c
index d615cf5..3a5d650 100644
--- a/conf.c
+++ b/conf.c
@@ -868,6 +868,7 @@ static int conf_runas(const char *opt, unsigned int *uid, unsigned int *gid)
 	(void)ubuf;
 	(void)gbuf;
 	(void)pw;
+	(void)gr;
 
 	return -EINVAL;
 #else