Hi folks, The following code fails to compile on OSX 10.8.5 with Xcode 5.0.1 and Boost 1.49.0. This is not real world code, but it demonstrates the problem I'm facing. #include template<typename T> void foo() { boost::zip_iterator > iter; std::fill(iter, iter, std::make_pair(T(),T())); } void bar() { foo<int>(); } Here are the commands I used to compile (if I drop "-stdlib=libc++" from the compile line, the code compiles just fine): setenv DEVELOPER_DIR /Applications/Xcode5.0.1.app/Contents/Developer xcrun -sdk macosx10.8 clang++ -c zip_iterator.cpp -I<boost-path>/include -std=c++11 -stdlib=libc++ and here is a heavily formatted snippet of the key error: /Applications/Xcode5.0.1.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/c++/v1/algorithm:1824:1: note: candidate function [with _RandomAccessIterator = boost::zip_iterator>, _Tp = std::__1::pair] not viable: no known conversion from typename iterator_traits>>::iterator_category (aka 'boost::detail::iterator_category_with_traversal') to 'std::__1::random_access_iterator_tag' for 4th argument __fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value_, random_access_iterator_tag) Any help is appreciated. Thanks, Jon