#16978: rephrase sentence and fix typo.  Initial patch by Tshepang Lekhonkhobe.
Issue #15989: Fix several occurrences of integer overflow
when result of PyLong_AsLong() narrowed to int without checks.

This is a backport of changesets 13e2e44db99d and 525407d89277.
Issue #16953: Fix socket module compilation on platforms with HAVE_BROKEN_POLL.
Patch by Jeffrey Armstrong.