[Bug c++/85739] internal compiler error: in finish_member_declaration, at cp/semantics.c:3057

["freddie_chopin at op dot pl" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85739

Freddie Chopin <freddie_chopin at op dot pl> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #44111|0                           |1
        is obsolete|                            |

--- Comment #2 from Freddie Chopin <freddie_chopin at op dot pl> ---
Created attachment 44116
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44116&action=edit
reduced and generic test case for gcc 8.1.0

I attach reduced test case for gcc 8.1.0. Interestingly today I cannot
reproduce the error for previous versions of gcc, which means that either I
just got confused yesterday or the triggering code is a bit different. So for
now let's ignore previous versions and focus on gcc 8.1.0.

Using the test case:

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$ g++ --version
g++ (GCC) 8.1.0
Copyright (C) 2018 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ g++ -c Scheduler-8.cpp -std=c++14

$ g++ -c Scheduler-8.cpp -std=c++17
Scheduler-8.cpp: In instantiation of ‘class B<l, &l::f>’:
Scheduler-8.cpp:29:20:   required from here
Scheduler-8.cpp:3:47: internal compiler error: in finish_member_declaration, at
cp/semantics.c:3057
 template <typename a, const int a::*> class B { using e = ptrdiff_t; };
                                               ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <https://bugs.archlinux.org/> for instructions.

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