Do you really think the "C community" as a whole will accept ANY syntax changes to the language?
From my experience I would say no. I think it would be "easier" to force tools on them than any syntax change (even if really really minor).
No. That's why I didn't push on this.
I have some disagreements with the design of Rust, but it's a big step forward.
Mind you, Ada/SPARK has been out there for quite some time now, and it has been a "big step forward" of what people were unaware, unfortunately. Only if Ada/SPARK got the hype of Rust... there would not be much of a need for Rust. Ada/SPARK would have an ideal ecosystem, perhaps even another compiler, and so on.
And you can get Annex K, on Windows.
On the other hand, exactly because of the way some C developers are against anything that helps security, is why Microsoft, Google, Oracle, ARM, Apple are all pursuing projects to have hardware memory tagging.
On Solaris SPARC, it already doesn't matter what those more religious developers think about bounds checking and similar issues.