Strange PV showed by Isa

[Daniel Anulliero]

If you notice another things , feel free to post here

Results with Nullmove look exactly identical to those without Nullmove, with all other search features being the same. That would imply to me that your Nullmove implementation is either not working at all, or only working in higher depths.

Thanks Sven !
I must look at my nulmove implementation yes !
I know the nulmove must be always an improvement for our engines , something wrong in Isa yes

[syzygy]

Of course you may *probe* at the root node but then use the result for move ordering only, not for cutting the subtree, that's what I meant.

If this is the explanation, which seems likely, then the real bug seems to be that tt entries are stored with the wrong depth when the king is in check. (The result returned at iteration 3 is accepted by iteration 4, which should not happen.)

When the king is in check, it is correct to increase the depth at which child nodes are searched, but one should not increase the depth at which the score for the present position is stored. This bug probably is not limited to root nodes.