[GHC] #11445: Turn on SplitSections by default

[GHC]

#11445: Turn on SplitSections by default
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        Reporter:  ezyang            |                Owner:
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Build System      |              Version:  8.0.1-rc1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:  11285
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by olsner):

 > So on ELF platforms -split-sections should be ready to replace -split-
 objs; further testing and investigation is necessary on Windows and OS X.

 OS X should just use the built-in subsection support.

 For non-Linux ELF platforms, an issue is that `--gc-sections` (under that
 name) is only available from GNU ld, other linkers might not have it or
 might call it something else. That means dropping `-split-objs` probably
 would leave some platforms without dead-code stripping at all.

 It should be good to go with GNU ld on non-Windows though. And for unixes
 without GNU ld we could get configure to check if the linker has something
 like `--gc-sections` and how to activate it. (Looks like e.g. Solaris has
 a `-z discard-unused=sections` flag.)

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11445#comment:3>
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