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Mate or not, Stockfish?

In this Queen vs Rook position, the cloud-based analysis says it's a draw (depth 61, evaluation "0")
lichess.org/analysis/standard/4k3/2Q5/4r3/6K1/8/8/8/8_w_-_-#0

However, after e.g. Qc8, stockfish (PNACL) quickly finds me a mate in 23 moves.

What's going on? Just an error in the cloud database, or something else? Is there a way for black to draw this against best play (I guess not?)?

(Just out of interest... I myself would not have the slightest chance to win this endgame with the queen against a computer or a good player...)

@ lovlas
Yes, that's what I read, that's why I'm wondering where the "0" computer evaluation is coming from. But maybe it's just a database glitch or something...

Could be. I was wondering if maybe the position was reached in some sort of threefold repetition fashion and therefor saved as a draw. But I have no idea, just speculating.

There is no Stockfish when Stockfish is accessible to 7 men TB.
When Tablebases are turned on ( within number of TB pieces), engines are automatically switched off.
If there is bug, it is not Stockfish, it is TB probe bug or GUI communication bug.

@drmrboss

good point. If you click on the tablebase, it indeed shows the winning moves for white, e.g. Kf5 - mate in 40. So I think the stored cloud analysis either didn't use the tablebase, and maybe the computer at this depth only found lines that take more than 50 moves. Or there was a technical communication/programming error or whatever.

In any case, happy to know that white wins, theoretically at least. (;

100% white mates
kf5 or kf4 best move ( lichess ,shredder endgame database win 21 )
my engine says mate in 22 ( no endgame database )
Engine says 0 because engine missed Qc8+

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