[Bug c++/84798] ICE (Segmentation fault) if `auto` appears in a template argument

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84798

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Started with r202540.  Before that:

error: parameter declared ‘auto’
 constexpr auto x = S<void(*)(auto)>::value;
                              ^