[GHC] #7898: SpecConstr explodes when compiling module BSP of frag-1.1.2

[GHC]

#7898: SpecConstr explodes when compiling module BSP of frag-1.1.2
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        Reporter:  tinctorius          |            Owner:
            Type:  bug                 |           Status:  new
        Priority:  normal              |        Milestone:
       Component:  Compiler            |          Version:  7.6.3
      Resolution:                      |         Keywords:
Operating System:  Unknown/Multiple    |     Architecture:
 Type of failure:  Compile-time crash  |  Unknown/Multiple
       Test Case:                      |       Difficulty:  Unknown
        Blocking:                      |       Blocked By:
                                       |  Related Tickets:
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Comment (by carter):

 a related instance of spec constr blowup was found in idris when built
 with O2
 where the javascript codegen module

 https://github.com/idris-lang/Idris-
 dev/blob/a68c5fa403145e7ce9ea0dc2d369c23ed6854e6d/src/IRTS/CodegenJavaScript.hs

 likewise
 http://pastebin.com/cvawjiCc
 the last line of the log is

 {{{
 *** SpecConstr:
 }}}

 not sure if this should be its own ticket or not, for now adding it here

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7898#comment:14>
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