[GHC] #4497: hmatrix-0.10.0.0 fails to build with GHC 7.0.1 (worked with 7.0.0.20101111)

[GHC]

#4497: hmatrix-0.10.0.0 fails to build with GHC 7.0.1 (worked with 7.0.0.20101111)
---------------------------------+------------------------------------------
    Reporter:  luite             |       Owner:                                          
        Type:  bug               |      Status:  new                                     
    Priority:  normal            |   Component:  Compiler                                
     Version:  7.0.1             |    Keywords:  hmatrix context reduction stack overflow
    Testcase:                    |   Blockedby:                                          
          Os:  Windows           |    Blocking:                                          
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown                            
---------------------------------+------------------------------------------
 When building hmatrix-0.10.0.0 with GHC 7.0.1 I get the following error.
 GHC 7.0.0.20101111 works fine. Increasing the context stack size only
 makes the error message longer.


 {{{
 lib\Numeric\LinearAlgebra\Tests.hs:242:33:
     Context reduction stack overflow; size = 21
     Use -fcontext-stack=N to increase stack size to N
       $dNum :: Num (Vector uf6)
       co :: e ~ uf6
       co :: RealOf e ~ e
       co :: RealOf uf5 ~ uf5
       co :: e ~ uf5
       co :: RealOf e ~ e
       co :: RealOf uf4 ~ uf4
       co :: e ~ uf4
       co :: RealOf e ~ e
       co :: RealOf uf3 ~ uf3
       co :: e ~ uf3
       co :: RealOf e ~ e
       co :: RealOf uf2 ~ uf2
       co :: e ~ uf2
       co :: RealOf e ~ e
       co :: RealOf uf1 ~ uf1
       co :: e ~ uf1
       co :: RealOf e ~ e
       co :: RealOf uf ~ uf
       co :: e ~ uf
       co :: RealOf e ~ e
     In the expression: norm2 a =~= sqrt (dot a a)
     In an equation for `norm2PropR':
         norm2PropR a = norm2 a =~= sqrt (dot a a)
     In an equation for `normsVTest':
         normsVTest
           = TestList
               [utest "normv2CD" $ norm2PropC v,
                utest "normv2CF" $ norm2PropC (single v),
                utest "normv2D" $ norm2PropR x, ....]
           where
               v = fromList [...] :: Vector (Complex Double)
               x = fromList [...] :: Vector Double
               norm2PropR a = norm2 a =~= sqrt (dot a a)
               norm2PropC a = norm2 a =~= realPart (sqrt (dot a (conj a)))
               ....
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4497>
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