mike wrote:
Sorry for my poor English,
Apparently, people understood the exact opposite of what I wanted to say.
FWIW, and IMO, your post was very good in laying out what dropping support for C++03 would mean. I'd only take exception to "a library can start using C++11 without warning and this is not considered a breaking change". That's like saying "1+1 is not considered 2". It's not a matter of consideration; if a change breaks code, it's a breaking change, regardless of whether one considers it to be such. It's generally up to the maintainer to decide how to proceed with breaking changes, whether caused by switching to C++11 or otherwise changing things in an incompatible way. ("It's generally up to the maintainer" is true for mostly everything in Boost, including whether to support C++03 or not.) We don't break code without a good reason not because of administrative rules and policies that forbid us from doing so; we don't break code without a good reason because this creates needless problems for our users and tarnishes our reputation and our brand.