1 files changed, 4 insertions, 1 deletions
diff --git a/error.c b/error.c
index 3b80a24bdd..03e22bfa3a 100644
--- a/error.c
+++ b/error.c
@@ -746,7 +746,10 @@ exc_equal(VALUE exc, VALUE obj)
 	CONST_ID(id_backtrace, "backtrace");
 
 	obj = rb_protect(try_convert_to_exception, obj, &status);
-	if (status || obj == Qundef) return Qfalse;
+	if (status || obj == Qundef) {
+	    rb_set_errinfo(Qnil);
+	    return Qfalse;
+	}
 	if (rb_obj_class(exc) != rb_obj_class(obj)) return Qfalse;
 	mesg = rb_check_funcall(obj, id_message, 0, 0);
 	if (mesg == Qundef) return Qfalse;