[MacPorts] #69812: /usr/bin/clang++ cannot compile anything when trying to compile as x86_64 on a current arm system against the MacOSX10.13.sdk (but macports-clang does work)

[MacPorts]

#69812: /usr/bin/clang++ cannot compile anything when trying to compile as x86_64
on a current arm system against the MacOSX10.13.sdk (but macports-clang
does work)
---------------------+--------------------
  Reporter:  lukaso  |      Owner:  (none)
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:          |
---------------------+--------------------

Comment (by lukaso):

 @kencu and @ryandesign, thanks so much for your help. Finally got to this.

 My workaround ended up being to compile against the current SDK since
 cmake-bootstrap is a build time dependency. I was actually facing this
 bug: https://trac.macports.org/ticket/66953 which affects `cmake-
 bootstrap` as well as `cmake`.

 My workaround is to do this:

 {{{
   sed -i -e 's/buildfromsource always/buildfromsource ifneeded/g'
 ${PREFIX}/etc/macports/macports.conf
   sed -i -e 's/macosx_deployment_target/#macosx_deployment_target/g'
 ${PREFIX}/etc/macports/macports.conf
   sed -i -e 's/macosx_sdk_version/#macosx_sdk_version/g'
 ${PREFIX}/etc/macports/macports.conf
   (
     # temporarily unset deployment targets since cmake does not build with
 10.13 SDK
     # and we don't really care since only used at build time
     # Can be removed once https://trac.macports.org/ticket/66953 is fixed
     unset MACOSX_DEPLOYMENT_TARGET
     unset SDKROOT
     echo "clean cmake-bootstrap****"
     port_clean_and_install cmake-bootstrap
   )
   sed -i -e 's/buildfromsource ifneeded/buildfromsource always/g'
 ${PREFIX}/etc/macports/macports.conf
   sed -i -e 's/#macosx_deployment_target/macosx_deployment_target/g'
 ${PREFIX}/etc/macports/macports.conf
   sed -i -e 's/#macosx_sdk_version/macosx_sdk_version/g'
 ${PREFIX}/etc/macports/macports.conf
 }}}

 For whatever reason, `cmake-bootstrap` wasn't being built as a dependency
 when I was building on true x86_64 so this appeared to be a rosetta 2
 issue to me.

 I apologize as I should have realized this was the case, and that I
 already had a workaround which I was using for `cmake`.

-- 
Ticket URL: <https://trac.macports.org/ticket/69812#comment:31>
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