[GHC] #7497: qsem001 and qsemn001 fail in HEAD

[GHC]

#7497: qsem001 and qsemn001 fail in HEAD
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        Reporter:  igloo             |         Owner:  simonmar
            Type:  bug               |        Status:  closed
        Priority:  normal            |     Milestone:
       Component:  Test Suite        |       Version:  7.7
      Resolution:  fixed             |      Keywords:
Operating System:  Unknown/Multiple  |  Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |     Test Case:
      Blocked By:                    |      Blocking:
 Related Tickets:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"85aa6ef09346e841abf4e089b24c7f783286cd74/ghc"
 85aa6ef0/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="85aa6ef09346e841abf4e089b24c7f783286cd74"
 Check generic-default method for ambiguity

 Fixes Trac #7497 and #12151.   In some earlier upheaval I introduced
 a bug in the ambiguity check for genreric-default method.

 This patch fixes it.  But in fixing it I realised that the
 sourc-location of any such error message was bogus, so I fixed
 that too, which involved a slightly wider change; see the
 comments with TcMethInfo.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7497#comment:2>
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