[GHC] #5631: Compilation slowdown from 7.0.x to 7.2.x

[GHC]

#5631: Compilation slowdown from 7.0.x to 7.2.x
---------------------------------+------------------------------------------
    Reporter:  bjpop             |        Owner:  simonpj                     
        Type:  bug               |       Status:  new                         
    Priority:  highest           |    Milestone:  7.4.1                       
   Component:  Compiler          |      Version:  7.2.1                       
    Keywords:                    |     Testcase:                              
   Blockedby:                    |   Difficulty:                              
          Os:  Unknown/Multiple  |     Blocking:                              
Architecture:  Unknown/Multiple  |      Failure:  Compile-time performance bug
---------------------------------+------------------------------------------

Comment(by simonmar):

 To remind us: we need to look into why `uType_defer` was being called here
 rather than unifying directly.  Simon PJ was suspicious.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5631#comment:7>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler