[Bug c++/102300] New: Qualified name in class template

[Bug c++/102300] New: Qualified name in class template

[huangqinjin at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

            Bug ID: 102300
           Summary: Qualified name in class template
           Product: gcc
           Version: 11.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: huangqinjin at gmail dot com
  Target Milestone: ---

template<typename T>
struct holder
{
    template<typename F> struct fn {};

    struct t1 : fn<T> {};                      // pass
    struct t2 : holder<T >::fn<T> {};          // fail
    struct t3 : holder<T >::template fn<T> {}; // fail
    struct t4 : holder<T*>::template fn<T> {}; // pass
};

The code compiles with GCC 10 but not GCC 11.

Output of x86-64 gcc 11.1 (Compiler #2)
<source>:7:35: error: expected class-name before '{' token
    7 |     struct t2 : holder<T >::fn<T> {};          // fail
      |                                   ^
<source>:8:44: error: expected class-name before '{' token
    8 |     struct t3 : holder<T >::template fn<T> {}; // fail
      |         


https://godbolt.org/z/qMav3YrYK

[Bug c++/102300] [11/12 Regression] Qualified name of same template in class template is rejected

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |rejects-valid
   Target Milestone|---                         |11.3
            Summary|Qualified name in class     |[11/12 Regression]
                   |template                    |Qualified name of same
                   |                            |template in class template
                   |                            |is rejected

[Bug c++/102300] [10/11/12 Regression] Qualified name of same template in class template is rejected

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
      Known to fail|                            |11.1.0, 11.2.0, 12.0
                 CC|                            |jason at gcc dot gnu.org,
                   |                            |ppalka at gcc dot gnu.org
            Summary|[11/12 Regression]          |[10/11/12 Regression]
                   |Qualified name of same      |Qualified name of same
                   |template in class template  |template in class template
                   |is rejected                 |is rejected
   Target Milestone|11.3                        |10.4
             Status|UNCONFIRMED                 |NEW
      Known to work|                            |10.3.0
   Last reconfirmed|                            |2021-09-13

--- Comment #1 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Started with r11-8035 (which was also backported to the 10 branch as r10-9851)

[Bug c++/102300] [10/11/12 Regression] Qualified name of same template in class template is rejected

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
If 10.3.0 worked this makes it P1.

[Bug c++/102300] [10/11/12 Regression] Qualified name of same template in class template is rejected

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |jason at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

[Bug c++/102300] [10/11/12 Regression] Qualified name of same template in class template is rejected

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jason Merrill <jason@gcc.gnu.org>:

https://gcc.gnu.org/g:30f2c22def7392119f1ffaca30ef998b3b43f336

commit r12-6754-g30f2c22def7392119f1ffaca30ef998b3b43f336
Author: Jason Merrill <jason@redhat.com>
Date:   Tue Jan 18 18:28:22 2022 -0500

    c++: template-id with current inst qualifier [PR102300]

    The patch for PR41723 properly changed one place to look into the current
    instantiation; now we need to fix this place as well.

            PR c++/102300

    gcc/cp/ChangeLog:

            * parser.cc (cp_parser_template_name): Use dependent_scope_p.

    gcc/testsuite/ChangeLog:

            * g++.dg/parse/no-typename1.C: Remove expected error.
            * g++.dg/template/nested7.C: New test.

[Bug c++/102300] [10/11 Regression] Qualified name of same template in class template is rejected

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11/12 Regression]       |[10/11 Regression]
                   |Qualified name of same      |Qualified name of same
                   |template in class template  |template in class template
                   |is rejected                 |is rejected
      Known to fail|12.0                        |
      Known to work|                            |12.0

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> ---
Fixed for 12 so far.

[Bug c++/102300] [10/11 Regression] Qualified name of same template in class template is rejected

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Note, this is only a P1 regression for 10.4, not for 11.3, because 11.1 and
11.2 had the bug too, while 10.3 didn't.

[Bug c++/102300] [10/11 Regression] Qualified name of same template in class template is rejected

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Jason Merrill
<jason@gcc.gnu.org>:

https://gcc.gnu.org/g:c2e39b9e1568484192c3a4c2b4425b06e701a3fe

commit r10-10730-gc2e39b9e1568484192c3a4c2b4425b06e701a3fe
Author: Jason Merrill <jason@redhat.com>
Date:   Thu May 12 17:08:52 2022 -0400

    Revert "c++: friend with redundant qualification [PR41723]"

            PR c++/102300
            PR c++/41723

    The patch for PR41723 caused PR102300 on trunk; let's just back it out on
    the 10 branch.

    This reverts commit e41d610696b81e72d1d06db176b281424e32fc23.

    gcc/testsuite/ChangeLog:

            * g++.dg/template/nested7.C: New test.

[Bug c++/102300] [11 Regression] Qualified name of same template in class template is rejected

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11 Regression]          |[11 Regression] Qualified
                   |Qualified name of same      |name of same template in
                   |template in class template  |class template is rejected
                   |is rejected                 |
   Target Milestone|10.4                        |11.4
           Priority|P1                          |P2

[Bug c++/102300] [11 Regression] Qualified name of same template in class template is rejected

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jason Merrill
<jason@gcc.gnu.org>:

https://gcc.gnu.org/g:8d2f59c8e26960df81e054c7afd2ef63171bae05

commit r11-9991-g8d2f59c8e26960df81e054c7afd2ef63171bae05
Author: Jason Merrill <jason@redhat.com>
Date:   Tue Jan 18 18:28:22 2022 -0500

    c++: template-id with current inst qualifier [PR102300]

    The patch for PR41723 properly changed one place to look into the current
    instantiation; now we need to fix this place as well.

    The fix for GCC 12 depends on r12-3643, so this commit also incorporates
    some of those changes.

            PR c++/102300

    gcc/cp/ChangeLog:

            * parser.c (cp_parser_template_name): Use dependent_scope_p.

    gcc/testsuite/ChangeLog:

            * g++.dg/parse/no-typename1.C: Remove expected error.
            * g++.dg/template/nested7.C: New test.

[Bug c++/102300] [11 Regression] Qualified name of same template in class template is rejected

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102300

Jason Merrill <jason at gcc dot gnu.org> changed:

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

--- Comment #8 from Jason Merrill <jason at gcc dot gnu.org> ---
Fixed for 11.4.