Turns out, that doesn't even fix the issue anyway

test-bot:
>`checking whether /private/tmp/capnp--clang-IkFH/clang+llvm-3.2-x86_64-apple-darwin11/bin/clang++ supports C++11 features by default... no
checking whether /private/tmp/capnp--clang-IkFH/clang+llvm-3.2-x86_64-apple-darwin11/bin/clang++ supports C++11 features with -std=gnu++11... no
checking whether /private/tmp/capnp--clang-IkFH/clang+llvm-3.2-x86_64-apple-darwin11/bin/clang++ supports C++11 features with -std=gnu++0x... no
checking whether /private/tmp/capnp--clang-IkFH/clang+llvm-3.2-x86_64-apple-darwin11/bin/clang++ supports C++11 features with -std=c++11... no
checking whether /private/tmp/capnp--clang-IkFH/clang+llvm-3.2-x86_64-apple-darwin11/bin/clang++ supports C++11 features with -std=c++0x... no
configure: error: *** A compiler with support for C++11 language features is required.
Error: capnp did not build
`