I made a build of the daemon last year on my w7-64 bit machine with msys2, and it worked fine for a few months. I recently rebuilt it with gcc5.2, db-4.8.30, openssl101p, boost 1.59, and gmp6 (not using miniupnpc or qrencode) and it seems to be working fine now for the past week. I do full static linking and everything is custom built, so it's not really a reproducable environment, but at least I did not have to make any changes to the source.