[GHC] #8333: The impossible happened with TH + -fno-omit-interface-pragmas

[GHC]

#8333: The impossible happened with TH + -fno-omit-interface-pragmas
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        Reporter:  errge       |            Owner:
            Type:  bug         |           Status:  patch
        Priority:  high        |        Milestone:  7.8.1
       Component:  Compiler    |          Version:  7.7
      Resolution:              |         Keywords:
Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple             |       Difficulty:  Easy (less than 1 hour)
 Type of failure:  GHCi crash  |       Blocked By:
       Test Case:              |  Related Tickets:
        Blocking:              |
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Changes (by klao):

 * cc: mihaly.barasz@… (added)
 * difficulty:  Unknown => Easy (less than 1 hour)
 * status:  new => patch


Comment:

 The attached patch contains an obvious easy fix.

 Another approach would be to change `TidyPgm` to remove the breakpoints
 even if -fno-omit-interface-pragmas is on. But, I don't see clearly what
 other consequences would that have. There was obviously a path to this
 panic from GHCi, but maybe it could also be triggered by someone using the
 GHC API directly.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8333#comment:1>
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