In A.27.1c on page 240, it says it is ok for c not to be mentioned in any clause, as it is const-qualified. That was true in OpenMP 3.0 where const-qualified having no mutable members were predetermined shared.
But as they aren't predetermined any longer, with default(none) I think they have to be mentioned in a shared(c) or firstprivate(c) clause.
Bug in A.27.1c testcase
Re: Bug in A.27.1c testcase
Thank you for your comment. You are indeed correct. It unfortunately also means that current programs using default(none) would fail, since it is no longer predetermined. The ARB usually tries to make sure that this doesn't happen, so we may have to revisit this to see whether it should be like a loop iteration variable (i.e., predetermined but allowed to be specified) so that current programs can continue to work. In any case, I have put your comment on the list of items to be reviewed before the specification is finalized.