[GHC] #1272: newStdGen returns the same value on successive calls

[GHC]

#1272: newStdGen returns the same value on successive calls
----------------------+-----------------------------------------------------
 Reporter:  guest     |          Owner:         
     Type:  bug       |         Status:  new    
 Priority:  normal    |      Milestone:         
Component:  Compiler  |        Version:  6.6    
 Severity:  normal    |     Resolution:         
 Keywords:            |     Difficulty:  Unknown
 Testcase:            |   Architecture:  Unknown
       Os:  Unknown   |  
----------------------+-----------------------------------------------------
Comment (by guest):

 Some more comments/experiments on this.

 (I'd submit a patch, but I don't understand the rationale behind the
 current implementation.)

 * Successive invocations of getClockTime always gives me  different
 results - even if the fraction is in even millions (i.e. µs).  So using
 the fraction would work on GHC at least.  Presumably there is a reason
 this isn't done already?

 * Initializing on modern Unixes (at least Linux and Solaris) should
 probably be from reading from /dev/urandom (/dev/random may block waiting
 for entropy - if an application depends on true randomness that
 critically, I think it should handle it manually.)  The current Read
 instance fails if it is fed strings longer than six characters, and the
 resulting StdGens from when it works appear limited in range.  This is
 probably not critical(?)

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1272>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler
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