[Bug c++/107897] [13 Regression] mangling conflicts with a previous mangle since r13-3601

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107897

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

https://gcc.gnu.org/g:a23b33a1bdeff7bc2289d9ebb7cb7b7ec0a605f5

commit r13-6944-ga23b33a1bdeff7bc2289d9ebb7cb7b7ec0a605f5
Author: Jason Merrill <jason@redhat.com>
Date:   Mon Mar 6 15:33:45 2023 -0500

    c++: lambda mangling alias issues [PR107897]

    In 107897, by the time we are looking at the mangling clash, the
    alias has already been removed from the symbol table by analyze_functions,
    so we can't look at n->cpp_implicit_alias.  So just assume that it's an
    alias if it's internal.

    In 108887 the problem is that removing the mangling alias from the symbol
    table confuses analyze_functions, because it ended up as first_analyzed
    somehow, so it becomes a dangling pointer.  So instead we call reset()
    to neutralize the alias.  To make this work for variables, I needed to move
    reset() from cgraph_node to symtab_node.

            PR c++/107897
            PR c++/108887

    gcc/ChangeLog:

            * cgraph.h: Move reset() from cgraph_node to symtab_node.
            * cgraphunit.cc (symtab_node::reset): Adjust.  Also call
            remove_from_same_comdat_group.

    gcc/cp/ChangeLog:

            * decl2.cc (record_mangling): Use symtab_node::reset.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/concepts-lambda3.C: Use -flto if supported.
            * g++.dg/cpp0x/lambda/lambda-mangle7.C: New test.