https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103923
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Here's a minimal program showing the underlying problem:
template<typename T, bool x = noexcept(T{}())>
struct C
{
};
struct T {
struct H {
auto operator()() const { return 0; }
};
C<H> c;
};
T t;
103923.C:1:43: error: use of 'auto T::H::operator()() const' before deduction
of 'auto'
1 | template<typename T, bool x = noexcept(T{}())>
| ~~~^~
103923.C:10:12: error: template argument 2 is invalid
10 | C<H> c;
| ^
