Re: [Bug-gnubg] Re: Bug? Pruning On/Pruning Off gives significantly different results at 4ply

[Michael Petch]

On 31/08/09 3:33 PM, "Øystein Johansen" <address@hidden> wrote:
> * /Should/ means that it should give the same answer. I have tested a lot of inputs and got the desired output, however..... there can be surprises.
Unless there is a bug or there is a precision change there is a difference between the outputs pre-patch and post patch versions. I am not the only one to have seen it. Now what I haven’t ruled out is that an unintended side effect of something else (optimizations, sse2 compiler bug etc).

I am running some eval tests today., When finished I will take out the latest CVS, and make 2 builds. No Multithreading with SSE only, and No Multithreading with SSE2 only (both builds with no compiler optimizations so no –O2 or -O3), I have a few thousand matches and I’ll analyze a random subset of the files on both versions (At 0 ply) and see if I can find any differences.