Function argument as __builtin_constant_p?

Is it possible to have a function argument which is __builtin_constant_p?

This macro works fine:

#define FOO(a) {\
    static_assert(__builtin_constant_p(a));\
}

void bar() {
    FOO("abc");
}

I would like to turn FOO into a function. However, this doesn't work:

void foo(const char* a) { // how to change argument to make this work?
    static_assert(__builtin_constant_p(a)); // Fails with: Static_assert failed due to requirement '__builtin_constant_p(a)
}

void bar() {
    foo("abc");
}

How can I change the argument of foo to make it work? Possibly using templates / std::forward or something similar?