Object pointer (this) saved in the constructor for later use seems to have incorrect value

Question

I came across a strange bug today, which basically boils down to the following minimal example:

#include <cassert>

struct S* ps;

struct S{
    S(){
        ps = this;
    }
    //~S(){} //(*)
};

S makeS(){
    return S{};
}

int main(){
    S s{makeS()};
    assert(&s == ps);
}

With guaranteed copy-elision, I believe that the assertion should never fail. However, when compiled with -std=c++20 in both gcc 13.1 and clang 16.0, the assertion would fail, as illustrated here. Increasing the optimization level does not help. If I uncomment the line marked (*) and add a user-provided destructor, then the assertion no longer fails. Why is that?

NOTE: I am intentionally creating a duplicate question for Copy elision and trivially copyable types as a signpost (which is allowed according to meta) because I have spent very long time before I finally found the answer.