Uniform initialization of non-copiable class data member cause to gcc error

Suppose we have this code:

class A
{
    public:

    A()=default;    
    A(const A &)=delete;
    ~A()=default;
};

class B
{
    public:

    B() : a{}
    {}

    A a[1];
};

int main() 
{
    B b;
}

This code compiles on latest gcc9.2, clang9.2, mvsc19.22.

But when I change A default c-tor to ~A(){} gcc returns error use of deleted function 'A::A(const A&)'. Clang and MSVC still compiles.

When I write copy c-tor to A gcc compiles, but in runtime this c-tor was never called. What gcc need copy c-tor for? Is it gcc bug (I`ve tried about all gcc versions on GodBolt.org - same error)?