Default operator error

default operator.cpp

class EmptyClass
{
    virtual ~EmptyClass() = default;
};

class DerivedFromEmpty: public EmptyClass
{
    bool operator==(const DerivedFromEmpty&) const = default;
};

// g++ -std=c++20 -c default.cc
// default.cc:6:7: error: deleted function ‘virtual DerivedFromEmpty::~DerivedFromEmpty()’
// overriding non-deleted function
//     6 | class DerivedFromEmpty: public EmptyClass
//       |       ^~~~~~~~~~~~~~~~
// default.cc:3:13: note: overridden function is ‘virtual constexpr EmptyClass::~EmptyClass()’
//     3 |     virtual ~EmptyClass() = default;
//       |             ^
// default.cc:6:7: note: ‘virtual DerivedFromEmpty::~DerivedFromEmpty()’ is implicitly deleted
// because the default definition would be ill-formed:
//     6 | class DerivedFromEmpty: public EmptyClass
//       |       ^~~~~~~~~~~~~~~~
// default.cc:6:7: error: ‘virtual constexpr EmptyClass::~EmptyClass()’ is private within this
// context default.cc:3:13: note: declared private here
//     3 |     virtual ~EmptyClass() = default;