[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
------------------------------------+--------------------------------
  Reporter:  ken-cunningham-webuse  |      Owner:  macports-tickets@…
      Type:  defect                 |     Status:  new
  Priority:  Normal                 |  Milestone:
 Component:  ports                  |    Version:  2.3.4
Resolution:                         |   Keywords:
      Port:  libcxxabi              |
------------------------------------+--------------------------------

Comment (by kencu):

 I think we have this fixed now. Some modifications to clang-5.0 appear to
 have done the trick, and the thread_local stuff looks like it's working on
 10.6.8 now (should also work on 10.4 and 10.5):
 {{{
 $ clang++ --version
 clang version 5.0.1 (tags/RELEASE_501/final)
 Target: x86_64-apple-darwin10.8.0
 Thread model: posix
 InstalledDir: /opt/local/libexec/llvm-5.0/bin
 }}}
 {{{
 $ cat thread.cpp
 #include <iostream>
 #include <string>
 #include <thread>
 #include <mutex>

 thread_local unsigned int rage = 1;

 std::mutex cout_mutex;

 void increase_rage(const std::string& thread_name)
 {
     ++rage; // modifying outside a lock is okay; this is a thread-local
 variable
     std::lock_guard<std::mutex> lock(cout_mutex);
     std::cout << "Rage counter for " << thread_name << ": " << rage <<
 '\n';
 }

 int main()
 {
     std::thread a(increase_rage, "a"), b(increase_rage, "b");

     {
         std::lock_guard<std::mutex> lock(cout_mutex);
         std::cout << "Rage counter for main: " << rage << '\n';
     }

     a.join();
     b.join();
 }
 }}}
 {{{
 $ clang++ -std=c++11 -o thread thread.cpp
 }}}
 {{{
 $ ./thread
 Rage counter for main: 1
 Rage counter for a: 2
 Rage counter for b: 2
 }}}

--
Ticket URL: <https://trac.macports.org/ticket/52585#comment:6>
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