diff --git a/abuild-rmtemp.c b/abuild-rmtemp.c
index 92c46cb..fd59f1f 100644
--- a/abuild-rmtemp.c
+++ b/abuild-rmtemp.c
@@ -18,7 +18,7 @@
 
 #define PREFIX "/var/tmp/abuild."
 
-static void fail() {
+static void fail(void) {
 	errx(1, "%s", strerror(errno));
 }