[MacPorts] #70655: Qt6-qtbase, missing #include and an issue for (some) older systems

[MacPorts]

#70655: Qt6-qtbase, missing #include and an issue for (some) older systems
-------------------------+---------------------------------
  Reporter:  Gandoon     |      Owner:  MarcusCalhoun-Lopez
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.10.1
Resolution:              |   Keywords:
      Port:  qt6-qtbase  |
-------------------------+---------------------------------

Comment (by reneeotten):

 You should not have been prompted to update Qt6 on macOS 10.15 as it’s not
 supported there - so no point sending this upstream…You instead should
 have stayed on 6.4.2 - at least that is how it was intended. So there is
 something not correct in the Qt6-related PortGroups and/or I made a
 mistake when doing the update; I’ll try to correct that.

 It appears to be tricky enough to get everything to build on upstream
 supported systems (likely related to SDK versions and such) and I don’t
 have the time/interest/capabilities to do the work to try and get it to
 work folr older OSes. Marcus has been doing a great job at that, but
 hasn’t been around much lately. So not sure of how much help I can be
 here… I am afraid that once you possibly fix this thing here it will break
 in other places and the patch-work will keep continuing.

-- 
Ticket URL: <https://trac.macports.org/ticket/70655#comment:3>
MacPorts <https://www.macports.org/>
Ports system for macOS