Stockfish 1.9.1 bug fix release for Chess960

[Jim Ablett]

Stockfish 1.91 JA by the Stockfish team.

Windows/Linux 64/32 Msvc/Intel p.g.o compiles.

This is just a bug fix release to restore chess960 support under some GUIs.

There is NO functional change and NO speed change, so absolutely NO
ELO change from 1.9 and people that has already tested 1.9 could
safely keep test results when switching to 1.9.1.


Download:
http://www.multiupload.com/60NG4URDX5
Mirror
http://good.net/_kRtRvnSPF


Jim.

[alpha123]

So did they just add the UCI_Chess960 option back, or did they do something more advanced?

Peter

[Graham Banks]

Stockfish 1.91 JA by the Stockfish team.

Thanks to the Stockfish team for addressing this issue so quickly, and thanks to you too Jim.

[Paloma]

This is just a bug fix release to restore chess960 support under some GUIs.

There is NO functional change and NO speed change, so absolutely NO
ELO change from 1.9 and people that has already tested 1.9 could
safely keep test results when switching to 1.9.1.
Jim.

Why is now the 32-bit Windows exe much smaller than the previous Version?

stockfish-191-32-ja.exe 206kb
stockfish-19-32-ja.exe 336Kb

Any reason?

[Jim Ablett]

This is just a bug fix release to restore chess960 support under some GUIs.

There is NO functional change and NO speed change, so absolutely NO
ELO change from 1.9 and people that has already tested 1.9 could
safely keep test results when switching to 1.9.1.
Jim.

Why is now the 32-bit Windows exe much smaller than the previous Version?

stockfish-191-32-ja.exe 206kb
stockfish-19-32-ja.exe 336Kb

Any reason?

Hi Herbert,

v1.91 32 bit = Msvc compiler.
v1.9 32 bit = Intel compiler.

1.91 has had a rewrite of the bit counting functions to make it more compatible.
The result of this is that the Msvc compiler produces slighty faster executables for me now than the Intel in win32.

Jim.

[ernest]

v1.91 32 bit = Msvc compiler.
v1.9 32 bit = Intel compiler.

1.91 has had a rewrite of the bit counting functions to make it more compatible.
The result of this is that the Msvc compiler produces slighty faster executables for me now than the Intel in win32.

Hi Jim,

On my (Intel) Core 2 Duo, in infinite analysis of the start_position, using only 1 thread (for reproducibility and precision), I find that:

for 32-bit: stockfish-19-32-ja.exe is 4.5% faster than stockfish-191-32-ja.exe
but
for 64-bit: stockfish-191-64-ja.exe is 2.6% faster than stockfish-19-64-ja.exe

with the consequence that:
for the 1.9 JA version, the 64-bit is 25.5% faster than the 32-bit
for the 1.9.1 JA version, the 64-bit is 33.8% faster than the 32-bit