From d0fec8d06cc2234c8114b51f630466eff9d5f841 Mon Sep 17 00:00:00 2001
From: Jakub Jelinek <jakub@redhat.com>
Date: Thu, 3 Mar 2005 13:34:35 +0000
Subject: Updated to fedora-glibc-20050302T1820

---
 posix/regcomp.c | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'posix/regcomp.c')

diff --git a/posix/regcomp.c b/posix/regcomp.c
index 1a5f7952c3..a7112cffdd 100644
--- a/posix/regcomp.c
+++ b/posix/regcomp.c
@@ -1321,6 +1321,11 @@ lower_subexp (err, preg, node)
   bin_tree_t *op, *cls, *tree1, *tree;
 
   if (preg->no_sub
+      /* We do not optimize empty subexpressions, because otherwise we may
+	 have bad CONCAT nodes with NULL children.  This is obviously not
+	 very common, so we do not lose much.  An example that triggers
+	 this case is the sed "script" /\(\)/x.  */
+      && node->left != NULL
       && (node->token.opr.idx >= 8 * sizeof (dfa->used_bkref_map)
 	  || !(dfa->used_bkref_map & (1 << node->token.opr.idx))))
     return node->left;
-- 
cgit v1.2.3-70-g09d2