[GHC] #14761: Incorrect diagnostic for UNPACK/missing strictness

[GHC]

#14761: Incorrect diagnostic for UNPACK/missing strictness
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        Reporter:  dminuoso          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #7210             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by osa1):

 I also agree that referring to `{-# UNPACK #-}` as "pragma" and `!` as
 "annotation" would be much better here.

 I'm also a bit surprised that `{-# UNPACK #-}` has such high precedence.
 This is not the case with some other annotations, e.g. `{-# SCC ... #-}`
 has quite low precedence so when I have `f = {-# SCC my_application #-} g
 a b c` it covers `g a b c` not just `g`. Because we can't unpack just some
 part of a field in a data con I think it'd make sense for `UNPACK` to have
 very low precedence. I think lowering the precedence would be backwards
 compatible too. Any thought on this?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14761#comment:6>
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