Fix for issue #7416: SIZEOF_UINTPTR_T can be invalid when configuring a multi-architecture build (in particular when the architectures don't share a common pointer size).
Fix for issue #7416: SIZEOF_UINTPTR_T can be invalid when configuring a
multi-architecture build (in particular when the architectures don't share
a common pointer size).

Fixed the same issue for SIZEOF_PTHREAD_T.

(No update to the NEWS file because this is a bugfix for an as yet unreleased
feature)

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator