https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123692
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Better reduced testcase:
```
struct a {
a(int);
bool operator==(a);
};
struct b : a {
using a::a;
};
b operator-(b, b);
extern b c;
extern a d;
decltype(d == c - 1) x;
```
