From 3a50c6828c87c11db07a66b3dd7ea4d2e7e223dd Mon Sep 17 00:00:00 2001
From: jzmaddock <john@johnmaddock.co.uk>
Date: Mon, 4 Nov 2024 18:12:47 +0000
Subject: [PATCH] Restrict fix to where we really need it.

---
 include/boost/regex/v5/perl_matcher_non_recursive.hpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/boost/regex/v5/perl_matcher_non_recursive.hpp b/include/boost/regex/v5/perl_matcher_non_recursive.hpp
index fb5d3edaa..92f6eb624 100644
--- a/include/boost/regex/v5/perl_matcher_non_recursive.hpp
+++ b/include/boost/regex/v5/perl_matcher_non_recursive.hpp
@@ -1204,8 +1204,10 @@ bool perl_matcher<BidiIterator, Allocator, traits>::skip_until_paren(int index,
       else if(pstate->type == syntax_element_startmark)
       {
          int idx = static_cast<const re_brace*>(pstate)->index;
-         match_startmark();
-         pstate = pstate->next.p;
+         if(idx > 0)
+            match_startmark();
+         else
+            pstate = pstate->next.p;
          skip_until_paren(idx, false);
          continue;
       }