[GHC] #10393: Bogus warning with OverloadedLists

[GHC]

#10393: Bogus warning with OverloadedLists
-------------------------------------+-------------------------------------
              Reporter:  goldfire    |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.10.1
              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:              |
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 When I say

 {{{
 {-# LANGUAGE OverloadedLists #-}

 lgo :: [a] -> ()
 lgo [] = ()
 lgo (_:_) = ()
 }}}

 I get

 {{{
 /Users/rae/temp/Bug.hs:4:1: Warning:
     Pattern match(es) are non-exhaustive
     In an equation for ‘lgo’: Patterns not matched: []
 }}}

 I don't know !OverloadedLists deeply, but that warning surely is
 confusing!

 Happens on both 7.8.3 and 7.10.1.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10393>
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