I'm trying to open one of my older projects, that was built using iOS 6.0. The project used to compile fine, but when opened under xCode 5, I get this cryptic error message. Unsupported compiler '...

I have a problem building Boost for Xcode 5 now that there is only one compiler LLVM 5.0. I've tried with Homebrew using --c++11, using clang.... I've tried various ideas and scripts but none has ...