[Bug c++/123075] New: ICE in get_keyed_decl_scope, at cp/module.cc:21808

[webrown.cpp at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123075

            Bug ID: 123075
           Summary: ICE in get_keyed_decl_scope, at cp/module.cc:21808
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: webrown.cpp at gmail dot com
  Target Milestone: ---

Created attachment 63021
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=63021&action=edit
bug3.cc: ICEs under 16.0

The attached file bug3.cc compiles cleanly for me with 15.2, but recent 16.0
(r16-5927...) complains:

  internal compiler error: in get_keyed_decl_scope, at cp/module.cc:21808

First encountered via `g++ -std=c++26 -fmodules-ts` on MacOS 15.7, and
reproduced by a colleague on x86_64-darwin and powerpc64le-linux.