Toolchain support for the C++11 standard [closed]

Question

I am currently updating my knowledge on C++ to the new standard. It makes me feel like a little kid that just got the awesomest toy: I want to play with it all the time but I don't want to lose my friends because of it.

I am involved in a few open source projects for which some of the new features would be extremely useful, so I am quite keen on using them. My question is how many users can compile C++11 code, e.g. what's the adoption rate of C++11-complete compilers in the general public? Does anyone have related information?

I know that gcc 4.8.1 and clang 3.3 are C++11 feature complete, but I have no idea how many people actually use compilers that are up to date. I know most codemonkeys surely do, but what about the average open source user? Slapping potential users in the face and telling them to update their compilers is not really an option.

I am aware that this question may be criticised/closed for being similar to these questions:

1. How are you using C++11 today?
2. To use or not to use C++0x features

I would like to point out that things are different now, since we are talking about an actual approved standard. I believe that being aware of its adoption rate is important in practice for programming.

Answer 1

You should probably first decide which C++11 you absolutely want to be able to use, and then lookup the lowest compiler version that supports this on the platforms that you want to support. Apache has a nice survey of the earliest version of each major compiler (gcc, clang, visual c++, intel, etc.) that supported the various C++11 features.

In my experience, gcc 4.7 and Clang 3.2 are almost feature complete (except for things like inheriting constructors, which are useful but not game changers). You could get a lot of useful features with gcc 4.6 (but take the 4.6.3 version to avoid many bugs) or Clang 3.1, which is nice since gcc 4.6 is also the official Android NDK compiler (if you are looking to support that).

If you are looking to support Linux, you can take a look at DistroWatch, where you can see which gcc versions were installed for each distro version. E.g. many popular distributions based on Ubuntu have been on gcc 4.7 for almost a year now, and are going to upgrade to gcc 4.8.1 (feature complete) in their next releases.

On Windows, there is the Nuwen Distro currently running MinGW 4.8.1 (only 32-bit and no threading). Visual C++ is not up to the job and will take a while (year or more?) to get where gcc 4.8 and Clang 3.3 are.

Even if the distros don't officially support a recent version, there are private package repositories (often maintained by the same people also doing the official packaging) that provide cutting edge. The LLVM project even provides pre-built nightly SVN snapshots that enable many of the C++14 features (in -std=c++1y mode). For gcc there are no nightly packages AFAIK.

About forcing developers to upgrade compilers / distros. I don't think it is such a big deal (but the point by @ArneMertz about consulting with them first, is very good here). Virtual machines are a breeze to install (~45 minutes end-to-end), so if you only want to release a binary-only product, then go ahead. For users that's another matter, so if you are providing a header-only template library that all regular users need to compile, that should make you a lot more conservative in your transition pace.