[MacPorts] #62293: clang-9.0 @ 9.0.1_3: Build failure on El Capitan with Xcode 7.3.1

[MacPorts]

#62293: clang-9.0 @ 9.0.1_3: Build failure on El Capitan with Xcode 7.3.1
---------------------------+--------------------
  Reporter:  SerpentChris  |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.6.4
Resolution:                |   Keywords:
      Port:  clang-9.0     |
---------------------------+--------------------

Comment (by kencu):

 Chris, before I do a deep dive here, could you take a moment and confirm
 for me that your Xcode matches your Command Line Tools, and that you have
 stock SDKs installed without any enhancements or symlinks added.

 This is just good MacPorts maintenance, but can cause confusion if there
 are any discrepancies. Here is mine on BigSur, for example:

 {{{
 % xcrun -find clang
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang

 %
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
 -v
 Apple clang version 12.0.0 (clang-1200.0.32.29)
 Target: x86_64-apple-darwin20.3.0
 Thread model: posix
 InstalledDir:
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

 % /Library/Developer/CommandLineTools/usr/bin/clang -v
 Apple clang version 12.0.0 (clang-1200.0.32.29)
 Target: x86_64-apple-darwin20.3.0
 Thread model: posix
 InstalledDir: /Library/Developer/CommandLineTools/usr/bin
 }}}

 and
 {{{
 % xcrun --show-sdk-path
 /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk

 % % ls -la
 /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/
 total 0
 drwxr-xr-x  5 root  wheel  160 26 Jan 21:39 .
 drwxr-xr-x  6 root  wheel  192 26 Jan 21:38 ..
 drwxr-xr-x  5 root  wheel  160 26 Jan 21:38 DriverKit20.2.sdk
 drwxr-xr-x  7 root  wheel  224 26 Jan 21:38 MacOSX.sdk
 lrwxr-xr-x  1 root  wheel   10 15 Dec 22:58 MacOSX11.1.sdk -> MacOSX.sdk

 % ls -la  /Library/Developer/CommandLineTools/SDKs
 total 0
 drwxr-xr-x  6 root  wheel  192 27 Jan 14:07 .
 drwxr-xr-x  5 root  wheel  160  2 May  2020 ..
 lrwxr-xr-x  1 root  wheel   14 27 Jan 14:07 MacOSX.sdk -> MacOSX11.1.sdk
 drwxr-xr-x  7 root  wheel  224 27 Jan 14:07 MacOSX11.1.sdk

-- 
Ticket URL: <https://trac.macports.org/ticket/62293#comment:1>
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