clang error on exception specification from C++20 on

This code compiles on gcc and msvc but not with clang from C++20 on:

#include <type_traits>

class IBase {
   protected:
    IBase() noexcept = default;

   public:
    virtual ~IBase() noexcept = default;
};

class Derived : public IBase {
   public:
    virtual ~Derived() noexcept(
        std::is_nothrow_destructible<IBase>::value) override = default;
};

LIVE

Up to C++17 included, gcc, msvc and clang compile this code but from C++20, clang rejects it with error: exception specification is not available until end of class definition.

Is it a clang bug or, on the contrary, a change in exception specification in C++20? How can I fix this code?

[EDIT] Based on the comments, here is a "more minimal reproducible example":

class IBase {
   public:
    virtual ~IBase() noexcept = default;
};

class Derived : public IBase {
   public:
    ~Derived() noexcept(true) override = default;
};

LIVE

Notice that the inheritance and both = defaultseem necessary to trigger the error.

How can I fix this code?

Although I don't know if this is a clang bug or not but I do know a workaround if you really want to =default the dtor.

In particular, you can =default outside the Derived class as shown below.

class Derived : public IBase {
   public:
    ~Derived() noexcept(true) ;
};
//default outside the class
Derived::~Derived() noexcept(true)= default;
int main() {
} 

Working demo