Macosx stream is clearly flagged

I am creating an application with C ++ 11 streams, but I cannot get it to work with clang ++ on MacOSX 10.9. Here's the simplest example I can find of what's causing the problems:

#include <thread>
#include <iostream>

class Functor {
  public:
    Functor() = default;
    Functor (const Functor& ) = delete;
    void execute () { 
      std::cerr << "running in thread\n";
    }
};

int main (int argc, char* argv[]) 
{
  Functor functor;
  std::thread thread (&Functor::execute, std::ref(functor));
  thread.join();
}

      

        
        
        
      

    

This compiles and works fine on Arch Linux using g ++ (version 4.9.2) with the following command line:

$ g++ -std=c++11 -Wall -pthread test_thread.cpp -o test_thread

      

        
        
        
      

    

It also compiles and works fine using clang ++ (version 3.5.0, also on Arch Linux):

$ clang++ -std=c++11 -Wall -pthread test_thread.cpp -o test_thread

      

        
        
        
      

    

But crashing on MacOSX 10.9.5 using XCode 6.1 (regardless of whether the -stdlib = libc ++ option is enabled):

$ clang++ -std=c++11 -Wall -pthread test_thread.cpp -o test_thread
In file included from test_thread.cpp:1:
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/thread:332:5: error: attempt to use a deleted function
    __invoke(_VSTD::move(_VSTD::get<0>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...);
    ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/thread:342:5: note: in instantiation of function template specialization
      'std::__1::__thread_execute<void (Functor::*)(), std::__1::reference_wrapper<Functor> , 1>' requested here
    __thread_execute(*__p, _Index());
    ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/thread:354:42: note: in instantiation of function template specialization
      'std::__1::__thread_proxy<std::__1::tuple<void (Functor::*)(), std::__1::reference_wrapper<Functor> > >' requested here
    int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Gp>, __p.get());
                                         ^
test_thread.cpp:19:15: note: in instantiation of function template specialization 'std::__1::thread::thread<void (Functor::*)(), std::__1::reference_wrapper<Functor> , void>'
      requested here
  std::thread thread (&Functor::execute, std::ref(functor));
              ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/type_traits:1001:5: note: '~__nat' has been explicitly marked deleted
      here
    ~__nat() = delete;
    ^
1 error generated.

      

        
        
        
      

    

I can't figure out how to get around this, it looks like a compiler error. For reference, clang version on that Mac:

$ clang++ --version
Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn)
Target: x86_64-apple-darwin13.4.0
Thread model: posix

      

        
        
        
      

    

Any ideas what I am doing wrong? Thank you! Donald.