[Bug c++/99445] [11 Regression] ICE in hashtab_chk_error, at hash-table.c:137 since r11-7011-g6e0a231a4aa2407b

[ppalka at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99445

--- Comment #5 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Reduced valid testcase:

template <class> struct implicit_conversions;
template <class T>
using implicit_conversions_t = typename implicit_conversions<T>::type;
template <class...> struct response_type;

template <class Handle, class... Ts>
using type1 = response_type<implicit_conversions_t<Ts>...>;

template <class Handle, class... Ts>
using type2 = response_type<typename implicit_conversions<Ts>::type...>;