[GHC] #11541: Type errors sometimes has a lot of irrelevant information

[GHC]

#11541: Type errors sometimes has a lot of irrelevant information
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        Reporter:  augustss          |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.8.3
      Resolution:                    |             Keywords:
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 Simon Peyton Jones <simonpj@…>):

 In [changeset:"18cd712427182e76d38047860ee3e26799bc3fe2/ghc" 18cd712/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="18cd712427182e76d38047860ee3e26799bc3fe2"
 Improve error message suppression

 TcErrors has a system for suppressing some type errors if a more
 serious one occurs.  But there was a crucial missing case, which
 sometimes resulted in a cascade of irrelevant errors overwhelming
 the actual cause. This was Trac #11541.

 The fix is simple.  Worth merging to 8.0
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11541#comment:6>
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