Do the padding bytes of a POD type get copied?

Question

Suppose I have a POD type like this:

struct A {
    char a;
    int b;
};

On my system, sizeof(A) == 8, even though size

Answer 1

It's not authoritative, but cppreference's entry for std::memcmp suggests that the padding bytes may differ:

memcmp() between two objects of type struct{char c; int n;} will compare the padding bytes whose values may differ when the values of c and n are the same