Tested with the latest master branch (01/03/2019), cross-compiled using https://github.com/bitcoin/bitcoin/blob/master/doc/build-windows.md instructions
When you simply run bitcoind.exe on Windows 10 64x, and your datadir has cyrillic or other funny unicode characters, it yields this error output:
2019-01-03T12:30:04Z Using BerkeleyDB version Berkeley DB 4.8.30: (April 9, 2010)
2019-01-03T12:30:04Z Using wallet wallet.dat
2019-01-03T12:30:04Z BerkeleyEnvironment::Open: LogDir=C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets\database ErrorFile=C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets\db.log
2019-01-03T12:30:04Z BerkeleyEnvironment::Open: Error -30974 opening database environment: DB_RUNRECOVERY: Fatal error, run database recovery
2019-01-03T12:30:04Z Moved old C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets\database to C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets\database.1546518604.bak. Retrying.
2019-01-03T12:30:04Z BerkeleyEnvironment::Open: LogDir=C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets\database ErrorFile=C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets\db.log
2019-01-03T12:30:04Z BerkeleyEnvironment::Open: Error -30974 opening database environment: DB_RUNRECOVERY: Fatal error, run database recovery
2019-01-03T12:30:04Z Error: Error initializing wallet database environment "C:\Users\Даниелька\AppData\Roaming\Bitcoin\wallets"!
Error: Error initializing wallet database environment "C:\Users\������������������\AppData\Roaming\Bitcoin\wallets"!
2019-01-03T12:30:04Z Shutdown: In progress...
2019-01-03T12:30:04Z scheduler thread interrupt
2019-01-03T12:30:04Z Shutdown: done
It happens both with explicitly set datadit and just default one. It is working fine with previous bitcoin releases, so must be some recent change triggering that one.