[GHC] #16120: Hadrian should use cabal build-tools installed Alex and Happy if necessary

[GHC]

#16120: Hadrian should use cabal build-tools installed Alex and Happy if necessary
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        Reporter:  adamse            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Build System      |              Version:  8.6.3
  (Hadrian)                          |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by snowleopard):

 Sounds great! If there are indeed no disadvantages then I think we should
 go ahead with this change.

 Do I understand correctly that this change is sufficient for the
 `configure` step to go through smoothly, because it can now see all
 required tools? Or do we also need to change the way we invoke the
 `configure` script from Hadrian?

 Another question: can/should we do the same change in the Stack build
 script?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16120#comment:9>
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