[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:  thoughtpolice
            Type:  bug                 |           Status:  new
        Priority:  highest             |        Milestone:  7.8.1
       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 thoughtpolice):

 hrrrrrrrrrrrrrgh.

 OK, so this patch mostly works but there's a problem; several libraries
 use `-fcpr-off` which is a !StaticFlag, meaning when it's passed to
 Haddock things mess up. Thinking about it, there are two other cases this
 could happen:

  * `-fno-state-hack`
  * `-fno-opt-coercion`

 To change this !StaticFlag would literally upset hundreds upon hundreds of
 call sites, and require substantial refactoring as it would introduce boot
 files and recursive dependencies across the frontend. Basically, the same
 thing I mentioned before.

 SimonH, me and Edsko are also a bit confused on how this randomly popped
 up out of nowhere as well. Perhaps Christiaan's patch is the way to go,
 but I don't like keeping code like this around since it seems broke. I'm
 not sure we have much of an option, however, until I get around to
 removing the remaining !StaticFlags. Which will take a while.

 Alternatively, we can still remove all this code, and simply special-case
 Haddock and !DocTest to totally ignore these flags and just not pass them
 to GHC. While they ''do'' affect how the optimizers work, I'm do not
 believe this could affect either Haddock or !DocTest in most situations.

 Thoughts?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8276#comment:36>
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