[MacPorts] #61544: unable to install qt5-qtbase on Big Sur

[MacPorts]

#61544: unable to install qt5-qtbase on Big Sur
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 Reporter:  ajsharff  |      Owner:  (none)
     Type:  defect    |     Status:  new
 Priority:  Normal    |  Milestone:
Component:  ports     |    Version:
 Keywords:            |       Port:
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 I am working on a Mac recently updated to MacOS 11 Big Sur.  I have
 successfully installed the latest version of MacPorts and have
 successfully installed many ports.

 However, I am unable to install a number of packages, particularly
 qt5-qtbase. I get the following messages:

 a) Warning: The macOS 11.0 SDK does not appear to be installed. Ports may
 not build correctly.

 The MacOSX11.0SDK is present in /Library/Developer/CommandLineTools/SDKs

 b) Warning: You can install it as part of the Xcode Command Line Tools
 package by running `xcode-select --install'.

 Xcode-select --install comes back saying the CLT are installed

 c) Sorry, "moc" cannot be run on this version of macOS. Qt requires macOS
 11.0.0 or later, you have macOS 10.16.0.

 This, I think is the kicker!!!!

 What is the solution?

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Ticket URL: <https://trac.macports.org/ticket/61544>
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