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

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}));
+}