[MacPorts] #58779: base: ports cannot use SDK inside of Developer dir unless using Xcode build type

[MacPorts]

#58779: base: ports cannot use SDK inside of Developer dir unless using Xcode build
type
---------------------+-----------------------
  Reporter:  Ionic   |      Owner:  (none)
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  base    |    Version:  2.5.99
Resolution:          |   Keywords:  tracemode
      Port:          |
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Comment (by Ionic):

 This snippet clears `${configure.sdk_version}`, yes. And yes, it does so
 if the selected SDK version doesn't exist. Qmake is special will use the
 default "macosx" SDK value in that case, i.e., figure out which SDK to
 use.

 Clemens's patch is fine. He's checking whether the developer dir has been
 determined as the CLT dir (i.e., is not the [default] Xcode developer dir,
 because use_xcode is false and Xcode should hence be avoided) and clears
 out `${configure.sdk_version}` if the requested SDK (relative to
 determined developer_dir) does not exist.

 My original attention call went out because of this line: `if { ![file
 exists ${configure.sdkroot}/MacOSX${configure.sdk_version}.sdk] } {`
 This will always be true, because `${configure.sdkroot}` will either be
 empty (in which case a file like `/MacOSX${configure.sdk_version}.sdk`
 will not exist) or set to an SDK root directory, such as
 `/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX${configure.sdk_version}.sdk`
 or
 `/Library/Developer/CommandLineTools/SDKs/MacOSX${configure.sdk_version}.sdk`.
 Coupled with yet another set of `MacOSX${configure.sdk_version}.sdk`, such
 a directory will not exist. You're currently checking for, e.g.,
 `/Library/Developer/CommandLineTools/SDKs/MacOSX${configure.sdk_version}.sdk/MacOSX${configure.sdk_version}.sdk`,
 which naturally won't exist.

-- 
Ticket URL: <https://trac.macports.org/ticket/58779#comment:16>
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