[Bug libstdc++/57465] New: Failed postcondition for std::function constructed with null function pointer

[Bug libstdc++/57465] New: Failed postcondition for std::function constructed with null function pointer

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465

            Bug ID: 57465
           Summary: Failed postcondition for std::function constructed
                    with null function pointer
           Product: gcc
           Version: 4.7.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org

#include <functional>
#include <cassert>

int main()
{
  using F = void();
  F* f = nullptr;
  std::function<F> x(f);
  assert( !x );
}

The assert should pass, but it fails with all versions.

Note that clang++ with libstdc++ headers passes the test, so this might be a
front end bug (to be filed separately) but can be fixed/worked around easily
enough in libstdc++ like so:

--- functional.orig     2013-05-30 10:48:27.081623873 +0100
+++ functional  2013-05-30 10:48:29.225370770 +0100
@@ -1964,7 +1964,7 @@

        template<typename _Tp>
          static bool
-         _M_not_empty_function(const _Tp*& __fp)
+         _M_not_empty_function(_Tp* const& __fp)
          { return __fp; }

        template<typename _Class, typename _Tp>

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2013-05-30
           Assignee|unassigned at gcc dot gnu.org      |redi at gcc dot gnu.org
     Ever confirmed|0                           |1

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Fri Sep 27 14:06:09 2013
New Revision: 202974

URL: http://gcc.gnu.org/viewcvs?rev=202974&root=gcc&view=rev
Log:
    PR libstdc++/57465
    * include/std/functional
    (_Function_base::_Base_manager::_M_not_empty_function): Fix overload
    for pointers.
    * testsuite/20_util/function/cons/57465.cc: New.

Added:
    trunk/libstdc++-v3/testsuite/20_util/function/cons/57465.cc
Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/std/functional

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Fixed on the trunk so far.

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Sun Oct  6 17:38:10 2013
New Revision: 203230

URL: http://gcc.gnu.org/viewcvs?rev=203230&root=gcc&view=rev
Log:
    PR libstdc++/57465
    * include/std/functional
    (_Function_base::_Base_manager::_M_not_empty_function): Fix overload
    for pointers.
    * testsuite/20_util/function/cons/57465.cc: New.

Added:
   
branches/gcc-4_8-branch/libstdc++-v3/testsuite/20_util/function/cons/57465.cc
Modified:
    branches/gcc-4_8-branch/libstdc++-v3/ChangeLog
    branches/gcc-4_8-branch/libstdc++-v3/include/std/functional

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED
   Target Milestone|---                         |4.8.2

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Fixed for 4.8.2, I'm not planning to backport this to the 4.7 branch though.

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465
Bug 57465 depends on bug 57466, which changed state.

Bug 57466 Summary: [DR 1584] Argument deduction fails for 'const T*' when T is function type
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57466

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

[Bug libstdc++/57465] Failed postcondition for std::function constructed with null function pointer

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57465
Bug 57465 depends on bug 57466, which changed state.

Bug 57466 Summary: [DR 1584] Argument deduction fails for 'const T*' when T is function type
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57466

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
         Resolution|FIXED                       |---