[GHC] #11941: stage restriction mentioned when an identifier is out of scope

[GHC]

#11941: stage restriction mentioned when an identifier is out of scope
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        Reporter:  aavogt            |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1-rc2
      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:"c2b7a3d9f6ad946a2cb2773e96a377cc2216cb5b/ghc" c2b7a3d/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="c2b7a3d9f6ad946a2cb2773e96a377cc2216cb5b"
 Avoid double error on out-of-scope identifier

 Trac #11941 demonstrated a case where an out-of-scope error also
 gave rise to a (bogus and confusing) stage restriction message.

 It's caused by the fact that out-of-scope errors do not stop
 renaming, but rather return an "unbound name".  We need to
 detect this in the stage-restriction test to avoid the double
 error.  Easy fix.
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11941#comment:1>
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