[MacPorts] #62816: Buildbot: building XCode project on 10.14.4 fails with: Swift does not support the SDK 'MacOSX10.14.sdk'

[MacPorts]

#62816: Buildbot: building XCode project on 10.14.4 fails with: Swift does not
support the SDK 'MacOSX10.14.sdk'
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  Reporter:  lhaeger        |      Owner:  admin@…
      Type:  defect         |     Status:  new
  Priority:  Normal         |  Milestone:
 Component:  buildbot/mpbb  |    Version:  2.6.4
Resolution:                 |   Keywords:
      Port:  AutoRaise      |
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Comment (by ryandesign):

 Pull requests and Buildbot have nothing to do with one another. For pull
 requests, mpbb runs on CI systems provided by GitHub. After a PR is merged
 or if a commit makes it to master by any other means, then mpbb runs via
 Buildbot on other servers.

 MacPorts defaults to the SDK version that matches the OS version because
 it cannot in general be assumed that any given port can build with an SDK
 that does not match the OS version. Some may handle this ok, but the
 authors of many software packages are not aware of Apple SDKs and their
 software will not work correctly in this case.

 `configure.sdk_version` is the version of the SDK (e.g. 10.15). Its
 default value is set from the `macosx_sdk_version` macports.conf value.

 `configure.sdkroot` is the absolute path to that SDK (e.g.
 /Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk).

 If the SDK MacPorts wants to use does not exist, then it uses the
 unversioned SDK (MacOSX.sdk), which may, as I mentioned above, cause some
 ports to fail to build or work correctly if that unversioned SDK does not
 match the OS version.

-- 
Ticket URL: <https://trac.macports.org/ticket/62816#comment:4>
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