[Bug c++/109420] New: [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X'

[Bug c++/109420] New: [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X'

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109420

            Bug ID: 109420
           Summary: [13 Regression] lookup of 'struct T::X' at
                    instantiation time does not ignore non-type bindings
                    of 'X'
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ppalka at gcc dot gnu.org
  Target Milestone: ---

struct A {
  struct X { };
  int X;
};

template<class T>
void f() {
  struct T::X x;
}

template void f<A>();

<stdin>: In instantiation of ‘void f() [with T = A]’:
<stdin>:11:20:   required from here
<stdin>:8:15: error: ‘typename A::X’ names ‘int A::X’, which is not a type

[Bug c++/109420] [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X'

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109420

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
      Known to fail|                            |13.0
   Target Milestone|---                         |13.0
           Assignee|unassigned at gcc dot gnu.org      |ppalka at gcc dot gnu.org
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2023-04-05
      Known to work|                            |12.2.0

--- Comment #1 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Started with r13-6098-g46711ff8e60d64

[Bug c++/109420] [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X'

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109420

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org
           Priority|P3                          |P1

[Bug c++/109420] [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X' since r13-6098-g46711ff8e60d64

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109420

--- Comment #2 from Patrick Palka <ppalka at gcc dot gnu.org> ---
FWIW a candidate fix has been posted at
https://gcc.gnu.org/pipermail/gcc-patches/2023-April/615250.html and will
hopefully get reviewed/pushed later this week

[Bug c++/109420] [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X' since r13-6098-g46711ff8e60d64

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109420

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

https://gcc.gnu.org/g:50dc52e853ff267ad1f4c98571c262017b0536f8

commit r13-7173-g50dc52e853ff267ad1f4c98571c262017b0536f8
Author: Patrick Palka <ppalka@redhat.com>
Date:   Thu Apr 13 16:02:21 2023 -0400

    c++: 'typename T::X' vs 'struct T::X' lookup [PR109420]

    r13-6098-g46711ff8e60d64 made make_typename_type no longer ignore
    non-types during the lookup, unless the TYPENAME_TYPE in question was
    followed by the :: scope resolution operator.  But there is another
    exception to this rule: we need to ignore non-types during the lookup
    also if the TYPENAME_TYPE was named with a tag other than 'typename',
    such as 'struct' or 'enum', since in that case we're dealing with an
    elaborated-type-specifier and so [basic.lookup.elab] applies.  This
    patch implements this additional exception.

            PR c++/109420

    gcc/cp/ChangeLog:

            * decl.cc (make_typename_type): Also ignore non-types during the
            lookup if tag_type corresponds to an elaborated-type-specifier.
            * pt.cc (tsubst) <case TYPENAME_TYPE>: Pass class_type or
            enum_type as tag_type to make_typename_type accordingly instead
            of always passing typename_type.

    gcc/testsuite/ChangeLog:

            * g++.dg/template/typename27.C: New test.

[Bug c++/109420] [13 Regression] lookup of 'struct T::X' at instantiation time does not ignore non-type bindings of 'X' since r13-6098-g46711ff8e60d64

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109420

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

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

--- Comment #4 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Fixed.