Non-type template argument evaluates to -1, which cannot be narrowed to type 'unsigned long long' xcode 4.6

I am using zxing and OpenCV lib in my project. I updated my XCode from 4.5 to 4.6 today and I am getting this error.

externalLibs/boost/include/boost/gil/channel_algorithm.hpp:54:85: Non-type template argument evaluates to -1, which cannot be narrowed to type 'unsigned long long'

And this error is on this line of code in one of the class of OpenCV Library:-

struct unsigned_integral_max_value : public mpl::
integral_c< UnsignedIntegralChannel,-1> {};

On Earlier version of Xcode its working fine.

Thanks in advance.

It seems boost doesn't like c++ 11 support added with the new clang compiler

so.. it say disable c++ 11 support in build settings

= src: see https://svn.boost.org/trac/boost/ticket/7270