[GHC] #5821: SPECIALISE fails with a cryptic warning

[GHC]

#5821: SPECIALISE fails with a cryptic warning
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        Reporter:  rl                |                   Owner:  ezyang
            Type:  bug               |                  Status:  patch
        Priority:  normal            |               Milestone:  7.10.1
       Component:  Compiler          |                 Version:  7.5
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  warning at compile-time            |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:  Phab:D610
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"788413297eaddfa259d2ab76459a916a62d2604c/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="788413297eaddfa259d2ab76459a916a62d2604c"
 Refactor handling of SPECIALISE pragmas (Trac #5821)

 The provoking cause was Trac #5821, which concerned
 type families, but in fixing it I did the usual round
 of tidying up and docmenting.

 The main comment is now
     Note [Handling SPECIALISE pragmas]
 in TcBinds.

 It is "wrinkle 2" that fixes #5821.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5821#comment:13>
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