[GHC] #15812: add System.Mem.Address to base

[GHC]

#15812: add System.Mem.Address to base
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        Reporter:  carter            |                Owner:  (none)
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:  8.10.1
       Component:  libraries/base    |              Version:  8.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D5268
       Wiki Page:                    |
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Comment (by carter):

 the discussion started in
 https://mail.haskell.org/pipermail/libraries/2018-October/028997.html
 (https://mail.haskell.org/pipermail/libraries/2018-October/thread.html)
 and continued through november
 https://mail.haskell.org/pipermail/libraries/2018-November/thread.html

 i'll write up more notes later, but ultimately the conclusion seems to be
 :

  1. theres not really any examples where the code becomes
 simpler/safer/more performant with Address in base and usage thereof
  2. there are valid/ real issues with some Ptr based interfaces and they
 could be improved. (and some confusion about why/best/practicies, and in
 one case the mistaken belief that all `Ptr a` values will conform to the
 Storable type class representation)


 there were ~ 3 people arguing for inclusion in base, but in my own opinion
 there wasn't a case substantiating their utility. (and some of the
 exemplar changes they suggested would needless break existing code without
 fixing any underlying issue, as best i could tell)

 Punchline: theres definitely a genuine need for better tooling around
 pointers to make its way into the ecosystem and perhaps eventually base,
 but this Adddress work doesn't accomplish that

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15812#comment:4>
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