Hi,
this is the LWG 467 bit about char_traits<char>::lt: since the member is
not used elsewhere in the library as an implementation detail and the
symbol is not exported, I think we can just unconditionally apply the
tweak and be done.
Tested x86_64-linux.
Thanks,
Paolo.
/////////////////////////
2013-06-24 Paolo Carlini <paolo.carl...@oracle.com>
PR libstdc++/57704
* include/bits/char_traits.h (char_traits<char>::lt): Implement
LWG 467.
* testsuite/21_strings/char_traits/requirements/char/57704.cc: New.
Index: include/bits/char_traits.h
===================================================================
--- include/bits/char_traits.h (revision 200380)
+++ include/bits/char_traits.h (working copy)
@@ -248,7 +248,11 @@
static _GLIBCXX_CONSTEXPR bool
lt(const char_type& __c1, const char_type& __c2) _GLIBCXX_NOEXCEPT
- { return __c1 < __c2; }
+ {
+ // LWG 467.
+ return (static_cast<unsigned char>(__c1)
+ < static_cast<unsigned char>(__c2));
+ }
static int
compare(const char_type* __s1, const char_type* __s2, size_t __n)
Index: testsuite/21_strings/char_traits/requirements/char/57704.cc
===================================================================
--- testsuite/21_strings/char_traits/requirements/char/57704.cc (revision 0)
+++ testsuite/21_strings/char_traits/requirements/char/57704.cc (working copy)
@@ -0,0 +1,37 @@
+// Copyright (C) 2013 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+ bool test __attribute__((unused)) = true;
+
+ char a = '\x7f';
+ char b = '\x80';
+
+ VERIFY( (std::char_traits<char>::lt(a, b)
+ == (static_cast<unsigned char>(a)
+ < static_cast<unsigned char>(b))) );
+}
+
+int main()
+{
+ test01();
+ return 0;
+}
