[MacPorts] #64088: cargo-c fails to build on 10.13

[MacPorts]

#64088: cargo-c fails to build on 10.13
-----------------------+---------------------------------
  Reporter:  bK4gYuRo  |      Owner:  MarcusCalhoun-Lopez
      Type:  defect    |     Status:  assigned
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.7.1
Resolution:            |   Keywords:  cargo-c
      Port:  cargo-c   |
-----------------------+---------------------------------

Comment (by bit-hug):

 Replying to [comment:23 tomio-arisaka]:
 > On the other hand,
 > when the options of "/opt/local/bin/rustc" include "-C
 linker=/opt/local/bin/clang-mp-13 -L
 /opt/local/libexec/llvm-13/lib/clang/13.0.0/lib/darwin", the phase of
 building succeeds.\\
 >
 > This case happens with the following commands:
 >
 > {{{
 > $ sudo port select --set clang mp-clang-13
 > $ sudo port install cargo-c
 > }}}

 Just to mention, if it's helpful, in my case, selecting Clang 13 as the
 default does not fix the issue.

 However, from my logs, it seems that the options of "/opt/local/bin/rustc"
 include "-C linker=/opt/local/bin/clang-mp-13 -L
 /Library/Developer/CommandLineTools/usr/lib/clang/10.0.0/lib/darwin"
 irrespective of the selected default clang.

 Otherwise, I have the following
 {{{
 $ sudo port -N rev-upgrade
 --->  Updating database of binaries
 --->  Scanning binaries for linking errors
 --->  No broken files found.
 --->  No broken ports found.
 $ sudo port diagnose
 $ /usr/bin/xcodebuild -version
 Xcode 9.2
 Build version 9C40b
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/64088#comment:27>
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