在Visual Studio中使用boost :: equality_comparable编译错误

Question

我已将示例代码最小化以重现此错误：

#include <boost/multiprecision/cpp_int.hpp>
#include <boost/operators.hpp>

// Evil
namespace Evil
{
    using BadGirl = boost::multiprecision::cpp_int;
    class BadBoy
        : public boost::totally_ordered2<BadBoy, BadGirl>
    {
    public:
        BadBoy() {}
    };
}

// Civilians
class Base // Abstract class inherited from boost::equality_comparable to get != operator for free
    : public boost::equality_comparable<Base>
{
    friend bool operator == ( Base const & lhs, Base const & rhs );    

public:
    Base() {}

    virtual void Whatever() const = 0;
};
// Implementation of equality operator
bool operator == ( Base const & /*lhs*/, Base const & /*rhs*/ )
{
    return true;
}

class Derived
    : public Base
{
public:
    Derived() {}
    void Whatever() const override {}
};

int main()
{
    Derived * derived1 = new Derived();
    Derived * derived2 = new Derived();
    Base * base1 = derived1;
    Base * base2 = derived2;

    // Calling the operator from the base class
    bool result = *base1 != *base2; // != operator is got for free from boost::equality_comparable.
    return 0;
}

代码的Evil部分会在编译期间导致失败，并抱怨cannot instantialize abstract class (base)。但它只能与cl重现。 G ++没有构建和运行它的问题。

知道为什么名称空间Evil内绝对独立的类可能会导致类Base和Derived出错？到目前为止，我只发现boost::multiprecision::cpp_int可以触发这个，但可能还有其他我不知道的情况。