What is the complexity of std::vector::clear() when T is a primitive type?

Question

I understand that the complexity of the clear() operation is linear in the size of the container, because the destructors must be called. But what about primitive types (and

Answer 1

gcc's version of std::_Destroy, which is what is eventually used by clear(), tries to template on on whether the type has a trivial destructor, so in that case the complexity is constant even without an optimisation pass. However I don't know how well the template works.