https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114764
--- Comment #7 from Giuseppe D'Angelo <dangelog at gmail dot com> ---
I get it :)
If you wanted an actual use-case (rather than a synthetic testcase), we
stumbled upon this bug from implementing a friend operator==:
```
class S {
bool comparesEqual(S, S) noexcept; // pass by value, object is
small/trivially copyable
friend inline bool operator==(S a, S b) noexcept(noexcept(comparesEqual(S,
S))) {
returns comparesEqual(a, b);
}
};
```
which is the result of some macro expansions through which we support C++20's
comparisons in C++17 in Qt. The problem is the pass by value -- changing it to
pass by const-ref fixes it, but generates different linting about not passing a
small TC object by value...
