C11 has seen new features, such as Generic Selection. Is the current language standardization converging (just adding clarifications, removing the surface for undefined behavior, etc.) or is C still growing with new features?
In other words, will the C standard be effectively “done” at some time in the future?
Fixing minor bugs or inconsistencies and reducing the number and kinds of instances of undefined behavior are some of the efforts keeping the C committee busy.
Reviewing proposals to incorporate features supported by common implementations is another.
Aligning with other standards (e.g., floating point) and improving compatibility with others (C++) is yet another.
In general, when an ISO standard is done it essentially becomes dead. So for the C standard to continue to be active (on ISO's books) it needs to evolve.
It's interesting to hear the standardization perspective, because it's pretty much the opposite of my perspective as a user.
I see the classic path of any programming language -- regardless of standardization -- is to continuously add features until it's too big and complex that nobody wants to deal with it any more. Then it's replaced by a newer, simpler language that takes the important bits and drops the unnecessary complexities. At that point, everybody sees that the older language was barking up the wrong tree, and they stop wasting time on it.
It's not the cessation of language change that causes language death -- that's merely a symptom. You can't keep a language alive simply by changing it every year. Some people sure have tried.
Alternatively, until it's evolved so much that there is so much diversity of implementation that simply knowing a library is written in "language X" doesn't tell me much about how it's written, or whether I can use it in my program which is also written in "language X".
Then again, C is the exception to every rule, so maybe we can keep piling on features indefinitely, and people will have to use it (even if they don't like it), for the same reason they started using it decades ago (even if we didn't like it).
I would say no, that we are still adding new features. Aaron Ballman was responsible for adding attributes to the C2x (he can tell you more). We're also looking at #embed feature to incorporate binaries the way that #include incorporates text.
In other words, will the C standard be effectively “done” at some time in the future?