[GHC] #10223: Cleanup `mk/build.mk.sample`

[GHC]

#10223: Cleanup `mk/build.mk.sample`
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        Reporter:  thomie            |                   Owner:  thomie
            Type:  task              |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by thomie):

 Todo:
 * figure out the `-H64m` story. See https://mail.haskell.org/pipermail
 /glasgow-haskell-users/2015-May/025917.html.


 I found this bit of wisdom by Simon Marlow,
 https://mail.haskell.org/pipermail/ghc-devs/2014-March/004344.html:

 > > Just wondering: that '-H64m' is from some old times (pre 2007?).
 > > GHC seems to eat way more RAM nowadays. Is this bit relevant at all?
 >
 > It still speeds up compilation a bit, but a larger -H value might be
 more appropriate > for today's machines.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10223#comment:11>
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