[GHC] #14092: hs-boot unfolding visibility not consistent between --make and -c

[GHC]

#14092: hs-boot unfolding visibility not consistent between --make and -c
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        Reporter:  ezyang            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  low               |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  hs-boot
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 duog):

 Replying to [comment:3 ezyang]:
 > Yes. But the price you pay is that the compilation of A and B can no
 longer be done in parallel. I tend to think of an hs-boot files as one way
 you could speed up compilation, a bit like header files, at the cost of
 the quality of optimized code.
 >

 I find this very convincing. Do you think this is a controversial view?

 > >  It's the simplifier that is doing more inlining than it should, isn't
 it? (Not the typechecker.)
 >
 > Yes!
 >

 The typechecker is providing the Ids with too many unfoldings attached
 though, right? Also see the example in comment 1 where a program
 typechecks because it can see a name that should be hidden to it.


 > > And how much does all this matter anyway?
 >
 > Not much, probably!
 >

 This is of interest to me because I am working on --make mode (trac:14095,
 trac:14103), and the treatment of hs-boot modules is by far the trickiest
 part. It seems that the correct behaviour isn't very well specified.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14092#comment:4>
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