[GHC] #1137: HashTable.hashString broken

[GHC]

#1137: HashTable.hashString broken
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    Reporter:  j.russell at alum.mit.edu  |       Owner:       
        Type:  bug                     |      Status:  new  
    Priority:  normal                  |   Milestone:       
   Component:  libraries/base          |     Version:  6.6  
    Severity:  normal                  |    Keywords:       
  Difficulty:  Unknown                 |    Testcase:       
Architecture:  x86                     |          Os:  Linux
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The output of HashTable.hashString is seriously broken in GHC 6.6.

 Here is a sample of the output with some strings zipped with their hash
 values:

 [(97,"a"),(59,"ba"),(74,"cba"),(69,"dcab"),(73,"edbac"),(72,"fecabd"),(73,"gfdbace"),(74,"hgecabdf"),(75,"ihfdbaceg"),(75,"jigecabdfh"),(76,"kjhfdbacegi"),(77,"lkigecabdfhj"),(77,"mljhfdbacegik"),(78,"nmkigecabdfhjl"),(79,"onljhfdbacegikm"),(80,"pomkigecabdfhjln"),(80,"qpnljhfdbacegikmo"),(81,"rqomkigecabdfhjlnp"),(82,"srpnljhfdbacegikmoq"),(83,"tsqomkigecabdfhjlnpr"),(83,"utrpnljhfdbacegikmoqs"),(84,"vusqomkigecabdfhjlnprt"),(85,"wvtrpnljhfdbacegikmoqsu"),(85,"xwusqomkigecabdfhjlnprtv"),(86,"yxvtrpnljhfdbacegikmoqsuw"),(87,"zywusqomkigecabdfhjlnprtvx")]

 The output from GHC 6.4.2, for comparison:

 [(97,"a"),(12641,"ba"),(134650,"cba"),(1348750,"dcab"),(686898,"edbac"),(531877,"fecabd"),(659882,"gfdbace"),(781094,"hgecabdf"),(924023,"ihfdbaceg"),(85405,"jigecabdfh"),(306085,"kjhfdbacegi"),(1152971,"lkigecabdfhj"),(1259361,"mljhfdbacegik"),(1179474,"nmkigecabdfhjl"),(489548,"onljhfdbacegikm"),(231688,"pomkigecabdfhjln"),(805762,"qpnljhfdbacegikmo"),(26414,"rqomkigecabdfhjlnp"),(1005367,"srpnljhfdbacegikmoq"),(394080,"tsqomkigecabdfhjlnpr"),(1010834,"utrpnljhfdbacegikmoqs"),(1178465,"vusqomkigecabdfhjlnprt"),(421802,"wvtrpnljhfdbacegikmoqsu"),(263363,"xwusqomkigecabdfhjlnprtv"),(1417299,"yxvtrpnljhfdbacegikmoqsuw"),(675868,"zywusqomkigecabdfhjlnprtvx")]

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1137>
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