[GHC] #10279: panic on haskell-src-exts

[GHC]

#10279: panic on haskell-src-exts
-------------------------------------+-------------------------------------
        Reporter:  throwaway123      |                   Owner:  ezyang
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Linux             |            Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash                              |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by ezyang):

 OK, it looks like at some point between 7.10 and HEAD the error message
 got better. But I don't know what the proximal commit was:

 {{{
 [ezyang at hs01 th]$ /home/hs01/ezyang/ghc-quick/inplace/bin/ghc-stage2
 --interactive T10279.hs -XTemplateHaskell
 GHCi, version 7.11.20150417: http://www.haskell.org/ghc/  :? for help
 [1 of 1] Compiling T10279           ( T10279.hs, interpreted )

 T10279.hs:5:10: error:
     Failed to load interface for ‘A’
     no package matching ‘base-4.8.1.0’ was found
     In the expression: (base-4.8.1.0:A.Foo)
     In an equation for ‘blah’: blah = (base-4.8.1.0:A.Foo)

 [ezyang at hs01 th]$ /home/hs01/ezyang/ghc-7.10/inplace/bin/ghc-stage2
 --interactive T10279.hs -XTemplateHaskell
 GHCi, version 7.10.0.20150317: http://www.haskell.org/ghc/  :? for help
 [1 of 1] Compiling T10279           ( T10279.hs, interpreted )

 T10279.hs:5:8:ghc-stage2: panic! (the 'impossible' happened)
   (GHC version 7.10.0.20150317 for x86_64-unknown-linux):
         qual_pkg base-4.8.1.0

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 }}}

 The error message is still pretty confusing but at least it is not a
 panic.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10279#comment:7>
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