[Bug c++/107033] [13 Regression] [modules] Variable template of type trait via importable header gives wrong result

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107033

--- Comment #6 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:099a66498bf7a40764002793eba66c881a251b76

commit r13-2878-g099a66498bf7a40764002793eba66c881a251b76
Author: Patrick Palka <ppalka@redhat.com>
Date:   Mon Sep 26 11:30:17 2022 -0400

    c++ modules: variable template partial spec fixes [PR107033]

    In r13-2775-g32d8123cd6ce87 I missed that we need to adjust the call to
    add_mergeable_specialization in the MK_partial case to correctly handle
    variable template partial specializations (it currently assumes we're
    always dealing with one for a class template).  This fixes an ICE when
    converting the testcase from that commit to use an importable header
    instead of a named module.

            PR c++/107033

    gcc/cp/ChangeLog:

            * module.cc (trees_in::decl_value): In the MK_partial case for
            a variable template partial specialization, pass decl_p=true to
            add_mergeable_specialization, and set spec to the VAR_DECL not
            the TEMPLATE_DECL.
            * pt.cc (add_mergeable_specialization): For a variable template
            partial specialization, set the TREE_TYPE of the new
            DECL_TEMPLATE_SPECIALIZATIONS node to the TREE_TYPE of the
            VAR_DECL not the VAR_DECL itself.

    gcc/testsuite/ChangeLog:

            * g++.dg/modules/partial-2.cc, g++.dg/modules/partial-2.h: New
            files, factored out from ...
            * g++.dg/modules/partial-2_a.C, g++.dg/modules/partial-2_b.C: ...
            these.
            * g++.dg/modules/partial-2_c.H: New test.
            * g++.dg/modules/partial-2_d.C: New test.