From dbc8cf059e0b7190337d6f7ef922e30fe67a30e2 Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Tue, 2 Jul 2013 17:43:31 +0000
Subject: [PATCH] Bill Fisher: This patch fixes a bug where the regex parser
 doesn't advance the pointer after reading the third character of an octal
 escape (in awk mode).

That is, regex{"\141", awk} results in the regular expression /a1/ instead of just /a/.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185449 91177308-0d34-0410-b5e6-96231b3b80d8
---
 CREDITS.TXT                                   |  4 +++
 include/regex                                 |  2 +-
 .../re.regex.construct/awk_oct.pass.cpp       | 28 +++++++++++++++++++
 3 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 test/re/re.regex/re.regex.construct/awk_oct.pass.cpp

diff --git a/CREDITS.TXT b/CREDITS.TXT
index 34a901f58..d75630a02 100644
--- a/CREDITS.TXT
+++ b/CREDITS.TXT
@@ -33,6 +33,10 @@ E: mclow.lists@gmail.com
 E: marshall@idio.com
 D: Minor patches and bug fixes.
 
+N: Bill Fisher
+E: william.w.fisher@gmail.com
+D: Regex bug fixes.
+
 N: Google Inc.
 D: Copyright owner and contributor of the CityHash algorithm
 
diff --git a/include/regex b/include/regex
index 022116720..312ca1144 100644
--- a/include/regex
+++ b/include/regex
@@ -3913,7 +3913,7 @@ basic_regex<_CharT, _Traits>::__parse_awk_escape(_ForwardIterator __first,
         {
             __val = 8 * __val + *__first - '0';
             if (++__first != __last && ('0' <= *__first && *__first <= '7'))
-                __val = 8 * __val + *__first - '0';
+                __val = 8 * __val + *__first++ - '0';
         }
         if (__str)
             *__str = _CharT(__val);
diff --git a/test/re/re.regex/re.regex.construct/awk_oct.pass.cpp b/test/re/re.regex/re.regex.construct/awk_oct.pass.cpp
new file mode 100644
index 000000000..11fce3fe0
--- /dev/null
+++ b/test/re/re.regex/re.regex.construct/awk_oct.pass.cpp
@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <regex>
+
+// template <class charT, class traits = regex_traits<charT>> class basic_regex;
+
+// template <class ST, class SA>
+//    basic_regex(const basic_string<charT, ST, SA>& s);
+
+#include <regex>
+#include <cassert>
+
+int main() 
+{
+    using std::regex_constants::awk;
+
+    assert(std::regex_match("\4", std::regex{"\\4", awk}));
+    assert(std::regex_match("\41", std::regex{"\\41", awk}));
+    assert(std::regex_match("\141", std::regex{"\\141", awk}));
+    assert(std::regex_match("\1411", std::regex{"\\1411", awk}));
+}