[GHC] #15157: Use a better string type (ByteString?!) for HsDocString

[GHC]

#15157: Use a better string type (ByteString?!) for HsDocString
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        Reporter:  sjakobi           |                Owner:  (none)
            Type:  task              |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.2.2
      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:D4743
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"d1beebb881722109d6935941e541eb175a9d6c62/ghc" d1beebb/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="d1beebb881722109d6935941e541eb175a9d6c62"
 Make HsDocString a newtype of ByteString

 Docstrings don't profit from FastString's interning, so we switch to
 a different type that doesn't incur this overhead.

 Updates the haddock submodule.

 Reviewers: alexbiehl, bgamari

 Reviewed By: alexbiehl, bgamari

 Subscribers: rwbarton, thomie, mpickering, carter

 GHC Trac Issues: #15157

 Differential Revision: https://phabricator.haskell.org/D4743
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15157#comment:2>
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