[Bug c++/94827] [10 Regression] crash on requires clause in tparam list since r10-4424

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94827

--- Comment #3 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
Created attachment 48425
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48425&action=edit
try instantiating the fn

This one ices with the initial patch.