[MacPorts] #52585: libcxxabi -- attempts to add thread-local-storage (TLS) to <10.9

[MacPorts]

#52585: libcxxabi -- attempts to add thread-local-storage (TLS) to <10.9
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  Reporter:  ken-cunningham-webuse  |      Owner:  macports-tickets@…
      Type:  defect                 |     Status:  new
  Priority:  Normal                 |  Milestone:
 Component:  ports                  |    Version:  2.3.4
Resolution:                         |   Keywords:
      Port:  libcxxabi              |
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Comment (by kencu):

 Well better, but not perfect. Sometimes, even though we're using
 `-femulated-tls`, a `_tlv_atexit` or `_tlv_init` still slips into the
 code, and doesn't find a link.

 I'm not sure why this happens inconsistently just now, but I wonder if it
 might have something to do with constructs such as this, in
 `llvm-5.0.1.src/tools/clang/lib/CodeGen/ItaniumCXXABI.cpp`:
 {{{
 const char *Name = "__cxa_atexit";
   if (TLS) {
     const llvm::Triple &T = CGF.getTarget().getTriple();
     Name = T.isOSDarwin() ?  "_tlv_atexit" : "__cxa_thread_atexit";
   }
 }}}

 It looks like on Darwin, `_tlv_*` codes might be assumed in certain
 places...

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Ticket URL: <https://trac.macports.org/ticket/52585#comment:7>
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