[MacPorts] #61396: rust @1.47.0: fails to build on Big Sur

[MacPorts]

#61396: rust @1.47.0: fails to build on Big Sur
-------------------------+--------------------
  Reporter:  5nefarious  |      Owner:  (none)
      Type:  defect      |     Status:  closed
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.6.99
Resolution:  invalid     |   Keywords:  bigsur
      Port:  rust        |
-------------------------+--------------------

Comment (by ryandesign):

 llvm-9.0 doesn't depend on qt5-qtbase. The only thing that could have
 happened is that you told MacPorts to upgrade llvm-9.0, MacPorts did
 upgrade it or though it was already up to date, MacPorts then ran rev-
 upgrade as it does after every installation or upgrade, found qt5-qtbase
 to be broken and tried to rebuild it, which failed for some reason.

 What output do you get when you run:

 {{{
 port installed llvm-9.0 libffi
 }}}

 Depending on the output, we can advise you how to fix your llvm-9.0.

-- 
Ticket URL: <https://trac.macports.org/ticket/61396#comment:9>
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