[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):

 Many thanks for checking @adamse! To me the difference in PATH settings
 between `new-run` and `new-exec` is surprising. Do you know about the
 rationale for this? If not, perhaps @hvr could clarify? I'm not suggesting
 to change anything, but merely want to learn a bit more about Cabal.

 Does switching from `new-run` to `new-exec` come with any disadvantages? I
 guess `new-exec` requires us to specify the path to the Hadrian executable
 which may be annoying. Is there anything else?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16120#comment:6>
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