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From: "Andrey A. Chernov" <ache@FreeBSD.org>
Date: Sun, 16 Feb 2003 19:52:35 -0800 (PST)
To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org,
	cvs-all@FreeBSD.org
Subject: cvs commit: src/lib/libc/stdlib rand.c
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ache        2003/02/16 19:52:35 PST

  Modified files:
    lib/libc/stdlib      rand.c 
  Log:
  Back out "drop first N values" method of removing monotonically increased
  seed->first value correlation. It breaks rand_r()... Other possible methods
  like shuffling inside aray will breaks rand_r() too, because it assumes
  only one word state, i.e. nothing extra can be added after seed assignment
  in srand().
  
  BTW, for old formulae seed->first value correlation is not so monotonically
  increased as with other Linear Congruential Generators of this type only
  becase arithmetic overflow happens. But overflow affects distribution
  and lower bits very badly, as many articles says, such type of overflow
  not improves PRNG.
  
  So, monotonically increased seed->first value correlation problem remains...
  
  Revision  Changes    Path
  1.15      +1 -7      src/lib/libc/stdlib/rand.c

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