re PR libstdc++/64649 (regex_traits::lookup_classname() only works with random access iterators)

	PR libstdc++/64649
	* include/bits/regex.tcc (regex_traits<>::lookup_collatename,
	regex_traits<>::lookup_classname): Correctly narrow input chars.
	* testsuite/28_regex/traits/wchar_t/user_defined.cc: New testcase.

From-SVN: r219986

libstdc++-v3/ChangeLog

+2015-01-22  Tim Shen  <timshen@google.com>
+
+	PR libstdc++/64649
+	* include/bits/regex.tcc (regex_traits<>::lookup_collatename,
+	regex_traits<>::lookup_classname): Correctly narrow input chars.
+	* testsuite/28_regex/traits/wchar_t/user_defined.cc: New testcase.
+
 2015-01-21  Jonathan Wakely  <jwakely@redhat.com>
 
 	* config/abi/pre/gnu.ver: Use [jmy] for size_t parameters.

libstdc++-v3/include/bits/regex.tcc

@@ -269,7 +269,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  "DEL",
 	};
 
-      string __s(__first, __last);
+      string __s;
+      for (; __first != __last; ++__first)
+	__s += __fctyp.narrow(*__first, 0);
+
       for (const auto& __it : __collatenames)
 	if (__s == __it)
 	  return string_type(1, __fctyp.widen(
@@ -311,8 +314,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       };
 
       string __s;
-      for (auto __cur = __first; __cur != __last; ++__cur)
-	__s += __fctyp.narrow(__fctyp.tolower(*__cur), '?');
+      for (; __first != __last; ++__first)
+	__s += __fctyp.narrow(__fctyp.tolower(*__first), 0);
 
       for (const auto& __it : __classnames)
 	if (__s == __it.first)

libstdc++-v3/testsuite/28_regex/traits/wchar_t/user_defined.cc

@@ -55,8 +55,32 @@ test01()
   VERIFY(!regex_match(L"\u2029", re));
 }
 
+struct MyCtype : std::ctype<wchar_t>
+{
+  char
+  do_narrow(wchar_t c, char dflt) const override
+  {
+    if (c >= 256)
+      return dflt;
+    return ((char)c)+1;
+  }
+};
+
+void
+test02()
+{
+  std::locale loc(std::locale(), new MyCtype);
+  std::regex_traits<wchar_t> traits;
+  traits.imbue(loc);
+  wchar_t wch = L'p';
+  VERIFY(traits.lookup_collatename(&wch, &wch+1) == L"q");
+  std::wstring ws = L"chfhs"; // chars of "digit" shifted by 1.
+  VERIFY(traits.lookup_classname(ws.begin(), ws.end()) != 0);
+}
+
 int main()
 {
   test01();
+  test02();
   return 0;
 }