This behavior is covered by the standard.  The following C translation unit is valid according to C99:

  struct PyTypeObject;
  extern struct PyTypeObject Foo_Type;
  struct PyTypeObject *ptr = &Foo_Type;

Specifically, &Foo_Type is an "address constant" per the standard because it is a pointer to an object of static storage duration (6.6p9).

The Python docs contradict this with the following incorrect statement:

> However, the unary ‘&’ operator applied to a non-static variable like PyBaseObject_Type() is not required to produce an address constant.

This statement is incorrect:

1. PyBaseObject_Type is an object of static storage duration.  (Note, this is true even though it does not use the "static" keyword -- the "static" storage-class specifier and "static storage duration" are separate concepts).

2. It follows that &PyBaseObject_Type is required to produce an address constant. because it is a pointer to an object of static storage duration.

MSVC rejects this standard-conforming TU when __declspec(dllimport) is added: https://godbolt.org/z/GYrfTqaGn  I am pretty sure this is out of compliance with C99.