[GHC] #2145: ghc does not terminate (renamer/typechecker?)

[GHC]

#2145: ghc does not terminate (renamer/typechecker?)
---------------------------+------------------------------------------------
    Reporter:  j.waldmann  |       Owner:          
        Type:  bug         |      Status:  new     
    Priority:  normal      |   Component:  Compiler
     Version:  6.8.2       |    Severity:  normal  
    Keywords:              |    Testcase:          
Architecture:  x86         |          Os:  Linux   
---------------------------+------------------------------------------------
 When doing

 {{{
 ghc --make -v SRS/Bounded/Paths.hs
 }}}

 the compiler seems stuck:

 {{{
 [5 of 5] Compiling SRS.Bounded.Paths ( SRS/Bounded/Paths.hs,
 SRS/Bounded/Paths.o )
 *** Parser:
 *** Renamer/typechecker:
 }}}

 Nothing happens, for minutes, and then I hit CTRL-C.

 The problem seems to be triggered by calls of "modify" in the line
 {{{
    edges = [ modify w1 af, new, modify w2  at ]
 }}}
 because if it is replaced with
 {{{
   edges = [ af, new, at ]
 }}}
 then compilation succeeds.

 {{{
 ghc --version
 The Glorious Glasgow Haskell Compilation System, version 6.8.2.20080113

 uname -a
 Linux noname 2.6.22.17-0.1-default #1 SMP 2008/02/10 20:01:04 UTC i686
 i686 i386 GNU/Linux
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2145>
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