clangbug.cpp

#include <iostream>
#include <string>
#include <vector>

class Base1 {
public:
  void foo() {
      std::cout << "Base1" << std::endl;
  }
};

class Base2 {
public:
    void foo() {
        std::cout << "Base2" << std::endl;
    }
};

template <typename... Bases>
class Derived : public Bases... {
};

template<typename... Bases>
void call_foo_on_bases(Derived<Bases...> derived) {
    using expander = int[];
    (void) expander {0, (derived.Bases::foo(), 0)...};
}



int main()
{
    call_foo_on_bases(Derived<Base1, Base2>());
}