[MacPorts] #63765: cmake +qt5 +docs +python39 hangs during build

[MacPorts]

#63765: cmake +qt5 +docs +python39 hangs during build
-------------------------+--------------------
  Reporter:  mouse07410  |      Owner:  (none)
      Type:  defect      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  cmake       |
-------------------------+--------------------

Comment (by pdvnl):

 for one of my macs running 10.13 high sierra (the others worked fine) i
 have the same problem:
 after
 {{{
 [100%] Built target CMakeLibTests
 }}}
 there is no more visible progress, but activity monitor shows around 100%
 cpu for python.

 {{{
 pstree 97542
 -+= 97542 macports /opt/local/libexec/macports/bin/tclsh8.5
 /opt/local/bin/port -dv upgrade cmake -docs-python38+python39
  \-+- 97549 macports sh -c  cd
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_relea
    \-+- 97550 macports /Library/Developer/CommandLineTools/usr/bin/make
 -j4 -w all VERBOSE=ON
      \-+- 97553 macports /Library/Developer/CommandLineTools/usr/bin/make
 -f CMakeFiles/Makefile2 all
        \-+- 97581 macports
 /Library/Developer/CommandLineTools/usr/bin/make -f
 Utilities/Sphinx/CMakeFiles/documentation.dir/bu
          \-+- 97583 macports /bin/sh -c cd
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_mac
            \--- 97584 macports
 /opt/local/Library/Frameworks/Python.framework/Versions/3.9/Resources/Python.app/Contents/MacOS/
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/63765#comment:10>
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