Hello, I'm a complete Boost newbie. I've been told very often that boost is the way to go for serious C++ coding, and I was not surprised to see such emphasis on the home page: "We aim to establish "existing practice" and provide reference implementations so that Boost libraries are suitable for eventual standardization" So when I used the format library on my existing (non-trivial) project and first compiled... I was very very surprised to get my neat compilation console flooded with hundreds of warnings ! I acknowledge I activate many many warnings: CXXFLAGS+=-Wall -Wextra -Wcast-qual -Wctor-dtor-privacy -Wdisabled-optimization \ -Wformat=2 -Winit-self -Wlogical-op -Wmissing-include-dirs \ -Wnoexcept -Woverloaded-virtual -Wredundant-decls -Wshadow \ -Wsign-conversion -Wsign-promo -Wstrict-null-sentinel -Wstrict-overflow=5 \ -Wswitch-default -Wundef -Wunused The warnings were as trivial as (for example): ../ext/boost/boost/type_traits/is_default_constructible.hpp:16:22: warning: "BOOST_GCC_VERSION_WORKAROUND_GUARD" is not defined [-Wundef] #if BOOST_WORKAROUND(BOOST_GCC_VERSION, < 40700) ../ext/boost/boost/format/parsing.hpp:435:67: warning: conversion to 'std::vector<boost::io::detail::format_item<char, std::char_traits<char>, std::allocator<char> >, std::allocator<boost::io::detail::format_item<char, std::char_traits<char>, std::allocator<char> > > >::size_type {aka unsigned int}' from 'int' may change the sign of the result [-Wsign-conversion] string_type & piece = (cur_item==0) ? prefix_ : items_[cur_item-1].appendix_; I understand they are only warning and the code is functionally correct and standard-wise correct. Personally when I face such false warnings in my code, I change the code to remove the warning so that if a warning does make sense, I can notice it. I thought a reference implementation would be written with such policy. There's no way I'm gonna read each of the hundreds of messages to understand if it is a mistake in my source code or a "shortcut" in boost library. So this is my first user experience. Not impressed at all. Boost will not be my reference.