4 ms·
No, it wouldn't disable the optimization, because a pointer 4 bytes into a live long long object isn't a valid pointer to another long long object that is live
by bonzini 7y ago
No, it wouldn't disable the optimization, because a pointer 4 bytes into a live long long object isn't a valid pointer to another long long object that is live at the same time (even though it could abstractly be a valid pointer to long long over the life of the program). If you want to disable the optimization you can use a union (which would also be technically UB but in practice compilers document that they do the right thing).