[MacPorts] #59342: cctools @921_3+llvm70: uses incorrect SDK taken from llvm-config-mp-7.0

[MacPorts]

#59342: cctools @921_3+llvm70: uses incorrect SDK taken from llvm-config-mp-7.0
----------------------------------+----------------------
  Reporter:  thomasrussellmurphy  |      Owner:  jeremyhu
      Type:  defect               |     Status:  assigned
  Priority:  Normal               |  Milestone:
 Component:  ports                |    Version:  2.6.1
Resolution:                       |   Keywords:
      Port:  cctools llvm-7.0     |
----------------------------------+----------------------

Comment (by EJFielding):

 In case someone else tries to follow what I did, installing an old version
 of Xcode only worked for a while. My employer has an automatic software
 upgrade system that installed Xcode 11.2 on top of Xcode 10.3. Apparently,
 it did not do a complete installation, so I then ended up with an
 inconsistent Swift library and xcodebuild would not run. I got a bunch of
 errors like this:

 {{{
 objc[48448]: Class __SwiftNativeNSDataBase is implemented in both
 /usr/lib/swift/libswiftCore.dylib (0x7fff94acce48) and
 /Applications/Xcode.app/Contents/Frameworks/libswiftCore.dylib
 (0x10633ded0). One of the two will be used. Which one is undefined.
 objc[48448]: Class __SwiftNativeNSIndexSetBase is implemented in both
 /usr/lib/swift/libswiftCore.dylib (0x7fff94acce98) and
 /Applications/Xcode.app/Contents/Frameworks/libswiftCore.dylib
 (0x10633df20). One of the two will be used. Which one is undefined.
 This copy of libswiftCore.dylib requires an OS version prior to 10.14.4.
 }}}

 It also seems like cctools is now fixed, so this issue can be closed.

-- 
Ticket URL: <https://trac.macports.org/ticket/59342#comment:10>
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