Possible Check Mate Bug

Hi I think there is a checkmate bug.

My black king was checkmated by the white queen supported by the white bishop.
However the white bishop was pinned down by my black rook that had line of sight attacking the white king. Therefore I should of been able to take the white queen with my black king.

White King G1
White Bishop G6
Black Rook G8
Black King F8
White Queen F7

I was check mated by the white queen how is this possible??

Because you are not allowed to move your king in to check. It's a rule of the game of chess. That's how it's played.

Because you were checkmated first. As a rule of thumb, you can't be in checkmate at all to get out of a check, even if the capture is illegal for the other player (a.k.a. what I just said).

because your king will get cut first

You can't put your king in check, even if the piece that is checking him is pinned.

Here's why: If you COULD put your king in check, then the bishop wouldn't be pinned. Your king would be taken before you could take white's king.

The bishop is still defending the queen even if it is pinned. Its a common mistake.

If a piece is pinned, it can help checkmate, even though it can't move.

Also a pinned piece can be a pinner itself, for the same reason!