[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 adamse):

 In hadrian subdirectory:

 {{{
 % which alex
 /Users/adam/.cabal/bin/alex

 % cabal new-exec which alex
 /Users/adam/.cabal/store/ghc-8.4.2/lx-3.2.4-ea33d38f/bin/alex
 }}}

 Running hadrian:
 {{{
 % ./hadrian/build.cabal.sh -c
 -- ...
 user interrupt

 % grep AlexCmd config.log
 AlexCmd='/Users/adam/.cabal/bin/alex'
 }}}

 So new-run and new-exec does not have the same behaviour with the PATH.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16120#comment:5>
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