title: Link iOS app against both libstdc++ and libc++
body: <p>Use case: I want to use a 3rd party static library that uses libstdc++ (cannot be changed), so I have to link my app against libstdc++. Now if I want to use C++11 features in my own code, I'd have to select libc++ in Xcode and additionally link against libstdc++ to satisfy the static library.</p>
  
  <p>My problem is that even though I selected libc++ in "Build settings" and added "-lstdc++" to "Other linker flags" (also tried via "Build phases > Link Binary With Libraries"), I'm getting linker errors for the latter, that is for libstdc++ functions/classes referenced by the 3rd party lib.</p>
  
  <p>How can I configure the project to link against both C++ standard libraries? It should theoretically be possible since libc++ will be in its own inline namespace <code>std::__1</code>.</p>