[MacPorts] #60032: MongoDB 4.2.3 fails to build on High Sierra

[MacPorts]

#60032: MongoDB 4.2.3 fails to build on High Sierra
------------------------+------------------------
  Reporter:  rseichter  |      Owner:  ryandesign
      Type:  defect     |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.6.2
Resolution:             |   Keywords:
      Port:  mongodb    |
------------------------+------------------------

Comment (by kencu):

 Same failure for me as well, on my High Sierra system. My system seems
 fully up to date, and lists no updates available.  Opening Xcode shows no
 instructions to update anything. It passes the configure Xcode 10 test,
 but does not have an Xcode that enables that {{{__builtin}}} function it
 appears.

 However, interestingly, it does seem to have slightly different versions
 of Xcode installed in the Xcode installation and in the Command Line Tools
 installation...

 {{{
 $     echo "macOS $(sw_vers -productVersion) $(sw_vers -buildVersion)";
 echo "Xcode $(xcodebuild -version | awk -v ORS=' ' '{print $NF}')"
 macOS 10.13.6 17G11023
 Xcode 10.1 10B61

 $ /usr/bin/clang -v
 Apple LLVM version 10.0.0 (clang-1000.11.45.5)
 Target: x86_64-apple-darwin17.7.0
 Thread model: posix
 InstalledDir:
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

 $ /Library/Developer/CommandLineTools/usr/bin/clang -v
 Apple LLVM version 10.0.0 (clang-1000.10.44.4)
 Target: x86_64-apple-darwin17.7.0
 Thread model: posix
 InstalledDir: /Library/Developer/CommandLineTools/usr/bin

 }}}

 Forcing the {{{mongodb}}} build against {{{macports-clang-9.0}}} works.

-- 
Ticket URL: <https://trac.macports.org/ticket/60032#comment:4>
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