[MacPorts] #66206: clang-11-bootstrap links opportunistically against libxml2

[MacPorts]

#66206: clang-11-bootstrap links opportunistically against libxml2
---------------------------------+-----------------------
  Reporter:  cave-canem          |      Owner:  catap
      Type:  defect              |     Status:  closed
  Priority:  Normal              |  Milestone:
 Component:  ports               |    Version:  2.8.0
Resolution:  worksforme          |   Keywords:  Mavericks
      Port:  clang-11-bootstrap  |
---------------------------------+-----------------------

Comment (by kencu):

 libxml2 is in the clang-dependency PortGroup.

 https://github.com/macports/macports-
 ports/blob/master/_resources/port1.0/group/clang_dependency-1.0.tcl

 MacPorts will never attempt to build libxml2 with any compiler listed in
 that PortGroup unless you try to force it to do so.

 after ICU is updated, libxml2 is revbumped, and will be built by a
 compiler that does not rely on libxml2. All is well, unless you take steps
 to break it, which you can probably do if you try.

 Now regarding clang-11-bootstrap, the idea of clang-11-bootstrap in the
 first place was that I envisioned it as an end-run around all this, and it
 would be a modern clang that work no matter what the status of any ports
 in Macports happened to be. clang-11-bootstrap tries to go to great
 lengths to avoid being entangled in any MacPorts ports.

 https://github.com/macports/macports-
 ports/blob/b01bdb8562ea4b611b5f406d70ba0cf3276e73c2/lang/clang-11-bootstrap/Portfile#L103

 That fact that a broken libxml2/icu situation made your clang-11-bootstrap
 not function is an interesting observation that we might have benefitted
 from sorting out, to see if there is in fact some way that
 clang-11-bootstrap did depend on something in macports.

 But we will never know what happened to you now. Nothing in the ticket
 above explains it. So we are lost and have to wait to see if someone else
 finds this issue again and perhaps we can work with them to see what is
 up.

 Maybe something to do with all the forcing of build compilers and forcing
 of versions of icu and possibly other similar things you were doing broke
 it?

 At any rate, this works for (almost) everyone throughout MacPorts. If it
 happens to you again, we would appreciate you trying to see what is going
 on for us, as if there is something that needs fixing, at present from
 this ticket, we can't know what it is.

-- 
Ticket URL: <https://trac.macports.org/ticket/66206#comment:21>
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