In an evergreen patch for an unrelated feature, I got a failure on OSX 64 nossl in the monogc-socket check_closed test. It seems like this test failed on the base patch as well. Here's the log for the base patch:
Here's the failure:
It looks like none of the commits since then have been to address this bug, so maybe it still exists, but just isn't being "triggered."
Forgive me if this is a duplicate.