[GHC] #13422: INLINE CONLIKE sometimes fails to inline

[GHC]

#13422: INLINE CONLIKE sometimes fails to inline
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #7206             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dfeuer):

 Reproduction instructions:

 Clone the `wip/cheapBuild` branch. Compile the following file:

 {{{#!hs
 module Ischeap where

 import Data.List

 foo :: Int -> Int
 foo n = s + p
   where
     nums = [1..n]
     s = sum nums
     p = product nums
 }}}

 using `ghc-stage2` with `-O2 -ddump-simpl`.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13422#comment:2>
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