[Bug c++/99208] [modules] ICE with partitions & instantiations of linkage-typedef structs

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99208

--- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Nathan Sidwell <nathan@gcc.gnu.org>:

https://gcc.gnu.org/g:47145e6916f58e1cd4f562c06fa7289da49f690c

commit r11-7347-g47145e6916f58e1cd4f562c06fa7289da49f690c
Author: Nathan Sidwell <nathan@acm.org>
Date:   Tue Feb 23 07:08:55 2021 -0800

    c++: typedef for linkage [PR 99208]

    Unnamed types with a typedef name for linkage were always troublesome
    in modules.  This is the underlying cause of that trouble -- we were
    creating incorrect type structures.  Classes have an implicit
    self-reference, and we created that for unnamed classes too.  It turns
    out we make use of this member, so just not generating it turned into
    a rathole.  This member is created using the anonymous name -- because
    we've not yet met the typedef name.  When we retrofit the typedef name
    we were checking identifier matching and changing all type variants
    with that identifier.  Which meant we ended up with a strange typedef
    for the self reference.  This fixes things to check for DECL identity
    of the variants, so we don't smash the self-reference -- that
    continues to have the anonymous name.

            PR c++/99208
            gcc/cp/
            * decl.c (name_unnamed_type): Check DECL identity, not IDENTIFIER
            identity.
            gcc/testsuite/
            * g++.dg/modules/pr99208_a.C: New.
            * g++.dg/modules/pr99208_b.C: New.