[GHC] #8787: compiler/ghc.mk: restore GhcHcOpts variable handling

[GHC]

#8787: compiler/ghc.mk: restore GhcHcOpts variable handling
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        Reporter:  slyfox            |            Owner:  thoughtpolice
            Type:  bug               |           Status:  patch
        Priority:  high              |        Milestone:  7.10.1
       Component:  Compiler          |          Version:  7.6.3
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by Austin Seipp <austin@…>):

 In [changeset:"423caa85db277a63df8c2aa071cada82d2181b6e/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="423caa85db277a63df8c2aa071cada82d2181b6e"
 compiler/ghc.mk: restore GhcHcOpts variable handling (Trac #8787)

 Summary:
 wiki and mk/config.mk.in suggests setting GhcHcOpts
 for compiler-wide haskell flags. But it does not
 work for a while now (broke around
 ca07d92837fc1e3ae9be67bb7d9e7f1b8035b00f)

 Signed-off-by: Sergei Trofimovich <slyfox at gentoo.org>

 Test Plan: 'make' shows now ghc timing as it used to be

 Reviewers: simonmar, austin

 Reviewed By: austin

 Subscribers: simonmar, relrod, carter

 Differential Revision: https://phabricator.haskell.org/D29
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8787#comment:3>
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