diff --git a/eval.c b/eval.c
index 8c8ac947f6..69a15d9985 100644
--- a/eval.c
+++ b/eval.c
@@ -755,6 +755,9 @@ rb_raise_jump(VALUE mesg, VALUE cause)
 void
 rb_jump_tag(int tag)
 {
+    if (UNLIKELY(tag < TAG_RETURN || tag > TAG_FATAL)) {
+	unknown_longjmp_status(tag);
+    }
     JUMP_TAG(tag);
 }
 
diff --git a/eval_error.c b/eval_error.c
index 0f2f165cc8..e907d7ee88 100644
--- a/eval_error.c
+++ b/eval_error.c
@@ -258,6 +258,9 @@ sysexit_status(VALUE err)
     return NUM2INT(st);
 }
 
+#define unknown_longjmp_status(status) \
+    rb_bug("Unknown longjmp status %d", status)
+
 static int
 error_handle(int ex)
 {
@@ -314,7 +317,7 @@ error_handle(int ex)
 	error_print();
 	break;
       default:
-	rb_bug("Unknown longjmp status %d", ex);
+	unknown_longjmp_status(ex);
 	break;
     }
     rb_threadptr_reset_raised(th);