[GHC] #10608: Compile error regression from GHC 7.10 to 7.11

[GHC]

#10608: Compile error regression from GHC 7.10 to 7.11
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        Reporter:  hvr               |                   Owner:  simonpj
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.11
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Other             |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"b5aabfbdb96ba8abf2748d089f40c267c2131215/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="b5aabfbdb96ba8abf2748d089f40c267c2131215"
 Infer types with flexible contexts

 Responding to Trac #10608 and Trac #10351, I've reverted
 to making type inference infer structured constraint like
     f :: C [t] => t -> t
 even if -XFlexibleContexts is not set.  That elicits an
 error message suggesting the flag.  The result is more
 helpful than the error message you get otherwise.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10608#comment:3>
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