[Bug c++/90966] [9/10 Regression] ICE in tsubst_copy, at cp/pt.c:16155

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90966

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Started with r263511.