[GHC] #15325: GHCi panic in getIdFromTrivialExpr with -fdefer-type-errors

[GHC]

#15325: GHCi panic in getIdFromTrivialExpr with -fdefer-type-errors
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        Reporter:  dramforever       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"2dbf88b3558c3b53a1207fb504232c3da67b266e/ghc"
 2dbf88b3/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="2dbf88b3558c3b53a1207fb504232c3da67b266e"
 Fix get getIdFromTrivialExpr

 This bug, discovered by Trac #15325, has been lurking since

   commit 1c9fd3f1c5522372fcaf250c805b959e8090a62c
   Author: Simon Peyton Jones <simonpj at microsoft.com>
   Date:   Thu Dec 3 12:57:54 2015 +0000

     Case-of-empty-alts is trivial (Trac #11155)

 I'd forgotttnen to modify getIdFromTrivialExpr when I
 modified exprIsTrivial.   Easy to fix, though.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15325#comment:5>
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