[GHC] #910: --make should have a -j flag for parallel building

[GHC]

#910: --make should have a -j flag for parallel building
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        Reporter:  igloo             |                Owner:
            Type:  feature request   |               Status:  closed
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  6.4.2
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  N/A
      Blocked By:  8184, 8235        |             Blocking:
 Related Tickets:  #9221             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by rrnewton):

 I want to raise one more issue on this topic.  Nowadays most people
 implicitly call ghc under layers of tooling (stack, cabal, ghc-mod,
 haskell-mode, etc).

 For example, with stack, at this particular moment in time I can't find a
 place to stick `-j3` such that all my builds on a machine will see it.

 This question of internal parallelism is an internal implementation issue,
 and shouldn't change semantics.  Thus I think it would be safe for it to
 be optionally controlled by an environment variable.  If I could just set
 "GHC_MAKE_CORES=3" on a given system, then I could get the desired
 behavior irrespective of what tools I'm using on top of GHC.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/910#comment:63>
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