diff --git a/src/test.c b/src/test.c
index 29ee7891596df1943ea83535bd4be121731febf5..4ec6bcfc815a92138c15b13eb1c09a1bb562ce7c 100644
--- a/src/test.c
+++ b/src/test.c
@@ -123,7 +123,7 @@ static void print_errors_in_solution(struct apk_database *db, int unsatisfiable,
 {
 	int i;
 
-	printf("%d unsatisfiable dependencies (solution with %d names)\n",
+	printf("%d unsatisfiable dependencies (solution with %zu names)\n",
 		unsatisfiable, solution->num);
 
 	for (i = 0; i < solution->num; i++) {