Tentative fix for #227. (#230)

Fixes #227.

Author: jzmaddock

include/boost/regex/v5/perl_matcher_non_recursive.hpp

@@ -1204,7 +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;
-         pstate = pstate->next.p;
+         if(idx > 0)
+            match_startmark();
+         else
+            pstate = pstate->next.p;
          skip_until_paren(idx, false);
          continue;
       }

test/Jamfile.v2

@@ -135,3 +135,4 @@ compile test_windows_defs_3.cpp ;
 compile test_windows_defs_4.cpp ;
 
 run issue153.cpp : : : "<toolset>msvc:<linkflags>-STACK:2097152" ;
+run issue227.cpp ;

test/issue227.cpp

@@ -0,0 +1,19 @@
+/*
+* Copyright (c) 2024
+* Christian Mazakas
+*
+* Use, modification and distribution are subject to the
+* Boost Software License, Version 1.0. (See accompanying file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+*/
+
+#include <boost/regex.hpp>
+#include <string>
+
+int main() {
+   boost::regex rx("(*ACCEPT)*+\\1((*ACCEPT)*+\\K)");
+   std::string str = "Z";
+   boost::smatch what;
+   boost::regex_search(str, what, rx, boost::match_default | boost::match_partial);
+}