[MacPorts] #59785: llvm ports opportunistically build ocaml binding even when +ocaml variant is not selected; leads to conflicts between them

[MacPorts]

#59785: llvm ports opportunistically build ocaml binding even when +ocaml variant
is not selected; leads to conflicts between them
--------------------------------+----------------------
  Reporter:  cooljeanius        |      Owner:  jeremyhu
      Type:  defect             |     Status:  assigned
  Priority:  Normal             |  Milestone:
 Component:  ports              |    Version:  2.6.2
Resolution:                     |   Keywords:
      Port:  llvm-7.0 llvm-9.0  |
--------------------------------+----------------------

Comment (by kencu):

 the various bindings (ocaml, go, python) that come with llvm* are detected
 opportunistically during a source installation, and are unfortunately not
 as simple to turn off as you might expect them to be. There should just be
 some simple cmake switches for them, and there are switches that seem
 related, but they don't really effectively turn the bindings off.

 And things, as I recall, changed in this area at certain points in the
 llvm life cycle.

 Last time I looked into this about 6 months ago, it was looking to take
 some cmake surgery to get this done. As these issues never seem to affect
 the buildbot versions of clang/llvm, which are built in clean environments
 where these go/ocaml etc bindings are never opportunistically detected, it
 doesn't come up for most people.

 I see you're building +universal so that must be why you are seeing this,
 and most don't.

 It is a bit of a pain, it should be fixed, upstream has declined to fix it
 and says things are fine as they are (in the email exchange I read about
 this last go round).

-- 
Ticket URL: <https://trac.macports.org/ticket/59785#comment:2>
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