1 files changed, 1 insertions, 1 deletions
diff --git a/eval.c b/eval.c
index 897ae7e602..3ee0b4d5da 100644
--- a/eval.c
+++ b/eval.c
@@ -9902,7 +9902,7 @@ rb_thread_atfork()
     if (rb_thread_alone()) return;
     FOREACH_THREAD(th) {
 	if (th != curr_thread) {
-	    rb_warn("fork terminates thread at %s:%s", th->node->nd_file, nd_line(th->node));
+	    rb_warn("fork terminates thread at %s:%d", th->node->nd_file, nd_line(th->node));
 	    rb_thread_die(th);
 	}
     }