Ah, interesting. https://bugs.python.org/issue30672 covered the fact that this test was already weird on FreeBSD, but the current status is that it was expecting BSD variants to act somewhat like Mac OS X, not like Linux.

I'm wondering if we may need to make test_c_locale_coercion less opinionated, where for most platforms it's just a "don't segfault" test, and it's only for ones where we're certain about how we expect it to behave (i.e. Linux, Mac OS X, AIX, maybe FreeBSD) that we try to check the specifics.