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Subject: Re: boundschecking

Author: Uri Blass

Date: 02:51:47 11/04/02

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On November 04, 2002 at 05:08:12, Uri Blass wrote:

>On November 04, 2002 at 05:07:11, Uri Blass wrote:
>
>>On November 04, 2002 at 04:59:03, Uri Blass wrote:
>>
>>>On November 04, 2002 at 04:32:20, Severi Salminen wrote:
>>>
>>>>>I can see randomize when I click F1 only as a visual basic command and I work in
>>>>>C.
>>>>>
>>>>>I tried srand(0) before filling the array but it does not help and
>>>>>zobrist[0][0][0] is different in debug mode and in release mode.
>>>>
>>>>Are you sure? I think rand() should return the exact same values if you use the
>>>>same seed (srand()). Are you sure you run srand(0) and fill the table only once
>>>>in both versions? There seems to be a bug somewhere.
>>>>
>>>>Severi
>>>
>>>I do not know maybe the problem is that I use rand64 for 64 bits numbers
>>>
>>>Here is the beginning of my code
>>>
>>>int main(void)
>>>{
>>>	char s[256];
>>>	int i=0;
>>>	char sizehash[9]="aaaaaaaaa";
>>>	int hash_in_mbytes=0;
>>>	FILE *hashfile=fopen("movei137info.txt", "r+t");
>>>	int fil,j;
>>>	srand(0);
>>>	for (fil=0;fil<6;fil++)
>>>		for (i=0;i<2;i++)
>>>			for (j=0;j<64;j++)
>>>				zobrist[fil][i][j]=rand64();
>>>			printf(" %d ",(zobrist[0][0][0]&1048575));
>>>
>>>
>>>In debug mode I get 229414 and in release mode I get 172695.
>>>
>>>
>>>If I use rand instead of rand64 I get 38 in both cases
>>>Here is my function rand64 that is in another file in my project.
>>>
>>>__int64 rand64()
>>>{
>>>	return rand()^((__int64)rand()<<15)^((__int64)rand()<<30)^
>>>		((__int64)rand()<<45)^((__int64)rand()<<60);
>>>}
>>>
>>>
>>>Uri
>>
>>More information the fact that the function is in a different files change
>>nothing here
>>
>>I tried transferring the function to the same file and even not using the
>>function but
>>having
>>
>>for (fil=0;fil<6;fil++)
>>		for (i=0;i<2;i++)
>>			for (j=0;j<64;j++)
>>				zobrist[fil][i][j]=rand()^((__int64)rand()<<15)^((__int64)rand()<<30)^
>>		((__int64)rand()<<45)^((__int64)rand()<<60);
>>
>>It does not help and I get different numbers in compile mode and in release
>>mode.
>
>Correction I mean debug and release.
>
>Uri

I did not try it at this moment but I guess that the problem is that the order
of the xor is different in debug and in release mode.

I am going to try it later today.

Uri



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