История изменений

$ cat main.cpp

template<typename T>
T& f()
{
    return *(T*)nullptr;
}

int main()
{
    int& a = f<int>();
}

$ clang++ -Wnull-dereference main.cpp
main.cpp:5:12: warning: binding dereferenced null pointer to reference has undefined behavior [-Wnull-dereference]
    return *(T*)nullptr;
           ^~~~~~~~~~~~
main.cpp:10:14: note: in instantiation of function template specialization 'f<int>' requested here
    int& a = f<int>();
             ^
1 warning generated.

$ cat main.cpp

template<typename T>
T& f()
{
    return *(T*)nullptr;
}

int main()
{
    int& a = f<int>();
}

$ clang++ -Wnull-dereference main.cpp
main.cpp:5:12: warning: binding dereferenced null pointer to reference has undefined behavior [-Wnull-dereference]
    return *(T*)nullptr;
           ^~~~~~~~~~~~
main.cpp:10:14: note: in instantiation of function template specialization 'f<int>' requested here
    int& a = f<int>();
             ^
1 warning generated.