[Bug c++/66405] [5/6 Regression] ICE: in tsubst, at cp/pt.c:11984

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66405

--- Comment #5 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Started with r217250 aka DR 1558.