Why must thrown objects be copy-initialized?

Question

Exceptions use the statical type of an object to copy-initialize the thrown object. For instance:

struct foo
{
    foo() = default;
    foo(const foo&) = delete;
};

int main()
{
    throw foo();
}

Clang++ --std=c++14 complains that the explicitly-deleted copy constructor can't be used. Why can't it be move-initialized instead?

Answer 1

It can't be move constructed because the type has no move constructor. A deleted copy constructor suppresses the implicit move constructor.

Answer 2

Modify the code to the following:

struct foo
{
    foo() = default;
    foo(const foo&) = delete;
    foo(foo&&) = default;
};

int main()
{
    throw foo();
}

Read this, the section "Implicitly-declared move constructor".