[GHC] #8276: Building Haddock documentation panics with perf build on x86_64 Linux

[GHC]

#8276: Building Haddock documentation panics with perf build on x86_64 Linux
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        Reporter:  jstolarek           |            Owner:
            Type:  bug                 |           Status:  new
        Priority:  high                |        Milestone:
       Component:  Documentation       |          Version:  7.7
      Resolution:                      |         Keywords:
Operating System:  Unknown/Multiple    |     Architecture:  x86_64 (amd64)
 Type of failure:  Compile-time crash  |       Difficulty:  Unknown
       Test Case:                      |       Blocked By:
        Blocking:                      |  Related Tickets:
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Comment (by darchon):

 The problem is that pretty-printing (code in `Outputable.hs`) an error
 tries to access the staticFlag "-dppr-debug". For some weird reason, the
 staticFlags are not parsed when the error message is converted to a
 String; that's the reason for this bug.

 The error that it is trying to print is #8320, but I don't think the error
 would only show up for that particular failure.

 What my patch does is not revert static flags to their unparsed state in
 the exception handling code of haddock. It makes this particular error go
 away, but it is not a proper fix. I find it weird that the exception
 handler can unparse the static flags before the error is converted to a
 string. Perhaps there is a way to force the error to printed before the
 staticFlags are unparsed?

 Also I want to point out that this bug, and the problem reported in
 https://github.com/sol/doctest-haskell/issues/59, are each others inverse:
 where the conflicting code in this bug expects staticFlags to be parsed,
 "kazu's" code expects the staticFlags not to be parsed yet.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8276#comment:15>
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