[MacPorts] #62329: clang-11: targeted OS version does not support -reexported_symbols_list on 10.6

[MacPorts]

#62329: clang-11: targeted OS version does not support -reexported_symbols_list on
10.6
-----------------------+--------------------
  Reporter:  mojca     |      Owner:  kencu
      Type:  defect    |     Status:  closed
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:  fixed     |   Keywords:
      Port:  clang-11  |
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Comment (by kencu):

 No -- to make the buildbot built it, we have to either:
 - turn off the part of clang that wants thread_local_storage (easy, but I
 have just been avoiding doing this) OR
 - make the buildbot finally install libc++ with thread_local_storage
 enabled

 I was hoping to do the latter, but so far the only way I can get that to
 happen on the buildbot is to just install a pre-built libc++ binary with
 thread_local_storage enabled.

 I think that is fine to do, but it has been (so far) disallowed.

 All the other tricky machinations that would be needed to make the system
 bootstrap to that thread_local_storage enabled libc++.dylib are just
 frankly too much of a PITA to actually consider doing.

 So we linger.

 My clang-11 (and 12, and devel, and ...) all built just fine on 10.6.8, as
 do all the 10.6.8 users' clangs, as (pretty much) every 10.6.8 user has
 done the 30 second procedure to upgrade their systems to the libc++ that
 has thread_local_storage enabled (it's a one-liner).

 BUT -- the buildbot is unable to do this, so the buildbot is uniquely
 broken.

-- 
Ticket URL: <https://trac.macports.org/ticket/62329#comment:15>
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