[Bug c++/100557] [concepts] Internal compiler error: Error reporting routines re-entered.

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100557

--- Comment #3 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Reduced:

template <typename _Tp> _Tp declval();

struct print_tag_;

bool tag_invoke(print_tag_, auto);
bool tag_invoke(print_tag_, auto obj) requires requires { *obj; };

template <typename CPO, typename... Args>
auto try_tag_invoke() noexcept(tag_invoke(declval<CPO>, declval<Args>()...))
    -> decltype(tag_invoke(CPO(), declval<Args>()...));

struct print_tag_ {
  void operator()(auto... args) noexcept(noexcept( try_tag_invoke<print_tag_,
decltype(args)...>()));
} print;

void foo() {
  print(0);
}