[GHC] #10346: Cross-module SpecConstr

[GHC]

#10346: Cross-module SpecConstr
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        Reporter:  simonpj           |                Owner:  ak3n
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  7.10.1
      Resolution:                    |             Keywords:  SpecConstr,
                                     |  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13016            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by ak3n):

 I am sorry, but what is the desired behaviour? I made a simple test with
 modules. The first module contains the drop function, while the second one
 calls it. At the current moment, both versions (ghc with the patch (D3566)
 and ghc 8.2.1) with enabled -O2 flag optimize the function with SpecConstr
 pass in the first module, and substitute the call to the optimized version
 into the second module.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10346#comment:8>
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