[GHC] #15227: Add PrelRules for par#

[GHC]

#15227: Add PrelRules for par#
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  low               |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:  Newcomer
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"feb8a671a4e92922ddac108686f0eace97dd331f/ghc" feb8a67/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="feb8a671a4e92922ddac108686f0eace97dd331f"
 Improve generated `GHC.Prim` docs

 Summary:
 * Extended `genprimcode` to generate Haddock-compatible deprecations,
   as well as displaying information about which functions are LLVM-only
   and which functions can fail with an unchecked exception.

 * Ported existing deprecations to the new format, and also added a
   deprecation on `par#` (see Trac #15227).

 * Emit an error on fixity/deprecation of builtins, unless we are
   processing the module in which that name is defined (see Trac #15233).
   That means the following is no longer accepted (outside of `GHC.Types`):

 ```
 infixr 7 :
 {-# DEPRECATED (:) "cons is deprecated" #-}
 ```

 * Generate `data (->) a b` with docs and fixity in `GHC.Prim`. This
   means: GHC can now parse `data (->) a b` and `infixr 0 ->` (only in
   `GHC.Prim`) and `genprimcode` can digest `primtype (->) a b` (See Trac
   #4861)

 as well as some misc fixes along the way.

 Reviewers: bgamari, RyanGlScott

 Reviewed By: RyanGlScott

 Subscribers: RyanGlScott, rwbarton, mpickering, carter

 GHC Trac Issues: #15227, #15233, #4861

 Differential Revision: https://phabricator.haskell.org/D5167
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15227#comment:4>
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