patch applied (ghc-7.0/ghc): Fix an egregious strictness analyser bug (Trac #4924)

[Ian Lynagh]

Fri Jan 28 00:07:48 PST 2011  simonpj at microsoft.com
  * Fix an egregious strictness analyser bug (Trac #4924)
  
  The "virgin" flag was being threaded rather than treated
  like an environment.  As a result, the second and subsequent
  recursive definitions in a module were not getting a
  correctly-initialised fixpoint loop, causing much worse
  strictness analysis results.  Indeed the symptoms in
  Trac #4924 were quite bizarre.
  
  Anyway, it's easily fixed.  Merge to stable branch.

    M ./compiler/stranal/DmdAnal.lhs -106 +123

View patch online:
http://darcs.haskell.org/cgi-bin/darcsweb.cgi?r=ghc-7.0/ghc;a=darcs_commitdiff;h=20110128080748-1287e-d2b60bca3d8b3a711951f7f8ffeaac70cd14f99b.gz