[GHC] #15519: Minor code refactoring leads to drastic performance degradation

[GHC]

#15519: Minor code refactoring leads to drastic performance degradation
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        Reporter:  danilo2           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:  SpecConstr
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by danilo2):

 @sgraf I would be truly surprised if 1% of library authors who ever used
 the INLINE pragma are aware how in reality it gets resolved. Moreover, you
 cannot rely on it because you don't have any clear guidance how to write
 high performance code with the current behavior, so I'm pretty sure there
 is nobody consciously relying on this behavior. I'd love to see this fixed
 according to SPJ proposal! :)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15519#comment:23>
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