[Bug c++/59173] New: Alias template in partial specialization finds name from primary template

[Bug c++/59173] New: Alias template in partial specialization finds name from primary template

[jhs at edg dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

            Bug ID: 59173
           Summary: Alias template in partial specialization finds name
                    from primary template
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jhs at edg dot com

In code such as the following, which is present in the <ext/extptr_allocator.h>
and <ext/pointer.h> headers, the type in the alias template definition finds
the rebind from the primary template.  The correct behavior is to give an error
because "rebind<_Up>" should be preceded by the "template" keyword for
syntactic disambiguation.

This is also a defect in those two headers as the template keyword should be
added there.

template<typename _Ptr>
struct pointer_traits
{
  template<typename _Up> struct rebind {};
};

template<typename T> struct P {};

template<typename T>
struct pointer_traits<P<T> >
{
  template<typename _Up>
     using rebind = P<typename pointer_traits<T>::rebind<_Up>>;
};

[Bug c++/59173] Alias template in partial specialization finds name from primary template

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Thanks for the report, John. I'll fix the library parts (assuming the corrected
versions still compile with G++)

[Bug c++/59173] Alias template in partial specialization finds name from primary template

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

--- Comment #2 from Paolo Carlini <paolo.carlini at oracle dot com> ---
It does, AFAICS.

[Bug c++/59173] Alias template in partial specialization finds name from primary template

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Wed Nov 20 13:39:33 2013
New Revision: 205114

URL: http://gcc.gnu.org/viewcvs?rev=205114&root=gcc&view=rev
Log:
    PR c++/59173
    * include/ext/pointer.h (pointer_traits<>::rebind<>): Add template
    keyword in nested name.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/ext/pointer.h

[Bug c++/59173] Alias template in partial specialization finds name from primary template

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |accepts-invalid
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-11-20
     Ever confirmed|0                           |1

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
John, I only found one problem in <ext/pointer.h>. Was the error in
<ext/extptr_allocator.h> due to including <ext/pointer.h>?

Confirming as a front-end bug anyway.

[Bug c++/59173] [10/11 Regression] Alias template in partial specialization finds name from primary template

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |10.4
      Known to fail|                            |10.1.0, 4.8.5
            Summary|Alias template in partial   |[10/11 Regression] Alias
                   |specialization finds name   |template in partial
                   |from primary template       |specialization finds name
                   |                            |from primary template
      Known to work|                            |4.9.0, 7.5.0, 9.3.0, 9.4.0

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So this was fixed in 4.9 and then broke again in GCC 10 so it is a regression.

[Bug c++/59173] [10/11 Regression] Alias template in partial specialization finds name from primary template

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.4                        |10.5

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 10.4 is being released, retargeting bugs to GCC 10.5.

[Bug c++/59173] [11/12/13/14 Regression] Alias template in partial specialization finds name from primary template

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11 Regression] Alias    |[11/12/13/14 Regression]
                   |template in partial         |Alias template in partial
                   |specialization finds name   |specialization finds name
                   |from primary template       |from primary template
      Known to fail|                            |10.5.0, 13.1.1

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
The testcase is still accepted.

[Bug c++/59173] [11/12/13/14 Regression] Alias template in partial specialization finds name from primary template

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59173

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.5                        |11.5