[Bug libstdc++/51185] New: [C++0x] false-positive results of std::is_constructible

[Bug libstdc++/51185] New: [C++0x] false-positive results of std::is_constructible

[ai.azuma at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51185

             Bug #: 51185
           Summary: [C++0x] false-positive results of
                    std::is_constructible
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ai.azuma@gmail.com


All of the static_asserts in the following code result in compile error with
-std=c++11.


////////////////////////////////////////
#include <type_traits>

struct A{};
struct B : A{};

int main()
{
  static_assert(!std::is_constructible<B &&, A>(), "");
  static_assert(!std::is_constructible<B const &&, A>(), "");
  static_assert(!std::is_constructible<B const &&, A const>(), "");
  static_assert(!std::is_constructible<B volatile &&, A>(), "");
  static_assert(!std::is_constructible<B volatile &&, A volatile>(), "");
  static_assert(!std::is_constructible<B const volatile &&, A>(), "");
  static_assert(!std::is_constructible<B const volatile &&, A const>(), "");
  static_assert(!std::is_constructible<B const volatile &&, A volatile>(), "");
  static_assert(!std::is_constructible<B const volatile &&, A const
volatile>(), "");
}
////////////////////////////////////////

[Bug libstdc++/51185] [C++0x] false-positive results of std::is_constructible

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51185

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |daniel.kruegler at
                   |                            |googlemail dot com

--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-11-17 10:18:19 UTC ---
Daniel, can you have a look?

[Bug libstdc++/51185] [C++0x] false-positive results of std::is_constructible

[daniel.kruegler at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51185

--- Comment #2 from Daniel Krügler <daniel.kruegler at googlemail dot com> 2011-11-17 10:58:09 UTC ---
(In reply to comment #1)
The root of the problem is that __is_base_to_derived_ref works on source
references solely. I need a bit time for a proper fix.

[Bug libstdc++/51185] [C++0x] false-positive results of std::is_constructible

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51185

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011-11-17
     Ever Confirmed|0                           |1

--- Comment #3 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-11-17 11:14:59 UTC ---
Thanks a lot!

[Bug libstdc++/51185] [C++0x] false-positive results of std::is_constructible

[paolo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51185

--- Comment #4 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> 2011-11-21 11:21:20 UTC ---
Author: paolo
Date: Mon Nov 21 11:21:13 2011
New Revision: 181557

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=181557
Log:
2011-11-21  Daniel Krugler  <daniel.kruegler@googlemail.com>

    PR libstdc++/51185
    * include/std/type_traits (__is_base_to_derived_ref,
    __is_lvalue_to_rvalue_ref): Fix.
    * testsuite/20_util/is_constructible/51185.cc: New.
    * testsuite/20_util/is_constructible/value-2.cc: Extend.

Added:
    trunk/libstdc++-v3/testsuite/20_util/is_constructible/51185.cc
Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/std/type_traits
    trunk/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
    trunk/libstdc++-v3/testsuite/20_util/is_constructible/value-2.cc
   
trunk/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc
   
trunk/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc

[Bug libstdc++/51185] [C++0x] false-positive results of std::is_constructible

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51185

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0
           Severity|minor                       |normal

--- Comment #5 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-11-21 11:24:27 UTC ---
Fixed.