The file `libImaging/Imaging.h` gets installed flat on
Ubuntus into the public Python includes.
When building a newer version of Pillow from source and
hinting the Python includes "too early" in includes, e.g.
in package managers, this can confuse the two files and
pick up the external file over the internal one. With
different versions, this mismatch can lead to build errors,
e.g. undefined macros.
The most robust way to avoid this is to pre-fix the internal
include accordingly, so that the relative path to the including
file has to match as well.
Compiler warning appeared as:
src/path.c:574:22: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
Py_TYPE(&item)->tp_name);
^~~~~~~
As item is already of type PyObject*, and the Py_TYPE macro is
equivalent to (((PyObject*)(o))->ob_type), no need for the dereference.
https://docs.python.org/3/c-api/structures.html#c.Py_TYPE
