[GHC] #15348: Enable two-step allocator on FreeBSD

[GHC]

#15348: Enable two-step allocator on FreeBSD
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  FreeBSD           |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4939
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"123aeb916cba93018039e583d42408dae80a6dc9/ghc"
 123aeb91/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="123aeb916cba93018039e583d42408dae80a6dc9"
 Enable two-step allocator on FreeBSD

 Simplify #ifdef nesting and use MAP_GUARD on FreeBSD and similar
 systems. This allows the two-step allocator to be used on FreeBSD,
 fixing #15348.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15348#comment:16>
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