noexcept规范中是否允许使用'this'?

*this ,但我希望它是友好的:

struct foo;

// Would actually be something with conditional noexcept
void do_something(foo&);

struct foo {
    void fn()
        noexcept(noexcept(::do_something(*this)))
    {
        ::do_something(*this);
    }
};

然而, gcc rejects this

<source>:7:43: error: invalid use of 'this' at top level
         noexcept(noexcept(::do_something(*this)))

如果我只访问一个成员,gcc就可以了:

void do_something(int);

struct bar {
    int x;

    void fn()
        noexcept(noexcept(::do_something(x)))
    {
        ::do_something(x);
    }
};

但是,如果我通过 this 指针, gcc complains again

struct baz {
    int x;

    void fn()
        noexcept(noexcept(::do_something(this->x)))
    {
        ::do_something(this->x);
    }
};

诊断的:

<source>:7:42: error: invalid use of 'this' at top level
         noexcept(noexcept(::do_something(this->x)))

accepts using this inside the noexcept specification

可以输入关键字吗 这 是否在无异常规范中使用?