[MacPorts] #64794: Cannot install ghc on arm

[MacPorts]

#64794: Cannot install ghc on arm
------------------------+--------------------
  Reporter:  essandess  |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:
      Port:  ghc alex   |
------------------------+--------------------

Comment (by essandess):

 Replying to [comment:2 jmroot]:
 > This is because alex, like every port that includes the haskell_stack
 portgroup, sets `supported_archs     x86_64`. If alex's architecture
 doesn't matter to ghc, use `depends_skip_archcheck`. Or if alex only
 installs an executable, it could set `installs_libs no`.

 I added `depends_skip_archcheck` to the `ghc` Portfile, but still
 encounter this error on arm:
 {{{
 --->  Computing dependencies for ghc
 Error: Cannot install ghc for the arch 'arm64' because
 Error: its dependency alex only supports the arch 'x86_64'.
 Error: Follow https://guide.macports.org/#project.tickets if you believe
 there
 is a bug.
 }}}

 BTW, I've been explicitly adding `ui_msg` statements to ensure that my
 edits are invoked, e.g.
 {{{
     # build depends upon x86_64 binary alex
     platform arm  {
         ui_msg "Port '${name}' on '${os.arch}'."
         depends_skip_archcheck
     }
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/64794#comment:4>
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