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Bug #71152 mt_rand() returns the different values from original mt19937ar.c
Submitted: 2015-12-17 19:13 UTC Modified: 2016-02-18 18:21 UTC
Votes:1
Avg. Score:3.0 ± 0.0
Reproduced:0 of 0 (0.0%)
From: kusano4a at gmail dot com Assigned:
Status: Closed Package: *Math Functions
PHP Version: master-Git-2015-12-17 (Git) OS: All
Private report: No CVE-ID: None
View Developer Edit
 [2015-12-17 19:13 UTC] kusano4a at gmail dot com 
Description:
------------
mt_rand() returns the different values from original mt19937ar.c.
Although mt_rand() is required to be generate random numbers, I am concerned about that this difference implies possibly deterioration of randomness quality.


Test script:
---------------
<?php
mt_srand(12345678);
for ($i=0; $i<10; $i++)
    echo mt_rand().PHP_EOL;


Expected result:
----------------
527860569
1711027313
1280820687
688176834
770499160
412773096
813703253
898651287
52508912
757323740


Actual result:
--------------
1614640687
1711027313
857485497
688176834
1386682158
412773096
813703253
898651287
2087374214
1382556330

Patches

Pull Requests

Pull requests:

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2016-02-17 03:35 UTC] laruence@php.net 
Automatic comment on behalf of kusano@users.noreply.github.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=6f6bd8ce531636134efd5f669a4e8373fb2e9e51
Log: Fix #71152: mt_rand() returns the different values from original mt19937ar.c
 [2016-02-17 03:35 UTC] laruence@php.net
-Status: Open +Status: Closed
 [2016-02-17 03:35 UTC] laruence@php.net 
Automatic comment on behalf of kusano@users.noreply.github.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=d31e8a9a85efea54db0b647424f6c4485d71db8b
Log: Fix #71152: mt_rand() returns the different values from original mt19937ar.c
 [2016-02-18 11:13 UTC] leigh@php.net 
Automatic comment on behalf of leigh
Revision: http://git.php.net/?p=php-src.git;a=commit;h=a0724d30817600540946b41e40f4cfc2a0c30f80
Log: Revert &quot;Fix #71152: mt_rand() returns the different values from original mt19937ar.c&quot;
 [2016-02-18 11:26 UTC] leigh@php.net 
Automatic comment on behalf of leigh
Revision: http://git.php.net/?p=php-src.git;a=commit;h=a0724d30817600540946b41e40f4cfc2a0c30f80
Log: Revert &quot;Fix #71152: mt_rand() returns the different values from original mt19937ar.c&quot;
 [2016-02-18 18:21 UTC] ab@php.net
-Status: Closed +Status: Re-Opened
 [2016-02-18 18:21 UTC] ab@php.net 
Reopen as the patch is reverted.

Thanks.
 [2016-04-18 09:30 UTC] bwoebi@php.net 
Automatic comment on behalf of kusano@users.noreply.github.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=d31e8a9a85efea54db0b647424f6c4485d71db8b
Log: Fix #71152: mt_rand() returns the different values from original mt19937ar.c
 [2016-04-18 09:30 UTC] bwoebi@php.net
-Status: Re-Opened +Status: Closed
 [2016-07-20 11:33 UTC] davey@php.net 
Automatic comment on behalf of leigh
Revision: http://git.php.net/?p=php-src.git;a=commit;h=a0724d30817600540946b41e40f4cfc2a0c30f80
Log: Revert &quot;Fix #71152: mt_rand() returns the different values from original mt19937ar.c&quot;
 [2016-07-20 11:33 UTC] davey@php.net 
Automatic comment on behalf of kusano@users.noreply.github.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=6f6bd8ce531636134efd5f669a4e8373fb2e9e51
Log: Fix #71152: mt_rand() returns the different values from original mt19937ar.c
 [2016-07-20 11:34 UTC] davey@php.net 
Automatic comment on behalf of kusano@users.noreply.github.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=d31e8a9a85efea54db0b647424f6c4485d71db8b
Log: Fix #71152: mt_rand() returns the different values from original mt19937ar.c
 
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