[Bug c++/88820] ICE in in C++2a mode for code which is able to be compiled in C++17 mode

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88820

--- Comment #5 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
This reduced test ICEs left and right with -std=c++17/14 since r236221, but the
ICE changed into another ICE with r248433.


template <__SIZE_TYPE__> class basic_fixed_string;
struct empty_subject;
template <basic_fixed_string> struct parser {
  template <typename = empty_subject> static auto trampoline_decide();
  bool correct = trampoline_decide();
};