Thanks for reporting the issue. That Gnulib file is shared with glibc, so I
installed the attached obvious fix there and am cc'ing the glibc list.
>From f615e3fced100914b1ee4d690f380deb69a4be70 Mon Sep 17 00:00:00 2001
From: Paul Eggert
Date: Wed, 21 Aug 2019 09:29:09 -0700
Subject: [PATCH]
Please consider applying this
diff --git a/lib/regex_internal.c b/lib/regex_internal.c
index 9004ce809..15f38a755 100644
--- a/lib/regex_internal.c
+++ b/lib/regex_internal.c
@@ -1311,7 +1311,6 @@ re_node_set_insert (re_node_set *set, Idx elem)
first element separately to skip a check in