Unintuitive move ctor behavior (gcc 5.2 in gnu++11 mode)

move.cc

#define IMPLICIT_DELETE_MEMBER 0
#define DEFAULT_KEYWORD_INSIDE 0

#include <utility>
#include <iostream>

struct Explicit {
    Explicit() = default;
    Explicit(const Explicit&) { std::cout<<"Explicit-Copy called\n"; }
    Explicit(Explicit&&) noexcept { std::cout<<"Explicit-Move called\n"; }
};
struct ExplicitDelete {
    ExplicitDelete() = default;
    ExplicitDelete(const ExplicitDelete&) = default;
    ExplicitDelete(ExplicitDelete&&) noexcept = delete;
};
struct ImplicitDelete : ExplicitDelete {};

static_assert(std::is_move_constructible<Explicit>::value, "");
static_assert(!std::is_move_constructible<ExplicitDelete>::value, "");
static_assert(std::is_move_constructible<ImplicitDelete>::value, "");

static_assert(std::is_nothrow_move_constructible<Explicit>::value, "");
static_assert(!std::is_nothrow_move_constructible<ExplicitDelete>::value, "");
static_assert(std::is_nothrow_move_constructible<ImplicitDelete>::value, "");

struct MyStruct {
    MyStruct() = default;
    MyStruct(const MyStruct&) = default;

#if DEFAULT_KEYWORD_INSIDE
    MyStruct(MyStruct&&) noexcept = default;
#else
    MyStruct(MyStruct&&) noexcept;
#endif

    Explicit exp; // will tell us whether an actual move was performed on MyStruct

#if EXPLICIT_DELETE_MEMBER
    ExplicitDelete del; // disallows move on MyStruct because its move ctor is deleted
#else
    ImplicitDelete del; // allows move on MyStruct even though its move ctor is deleted
#endif
};

#if ! DEFAULT_KEYWORD_INSIDE
inline MyStruct::MyStruct(MyStruct&&) noexcept = default;
#endif

static_assert(std::is_move_constructible<MyStruct>::value, "");

#if EXPLICIT_DELETE_MEMBER
static_assert(!std::is_nothrow_move_constructible<MyStruct>::value, "");
#else
static_assert(std::is_nothrow_move_constructible<MyStruct>::value, "");
#endif

int main() {
    MyStruct s1;
    MyStruct s2(std::move(s1));
    return 0;
}