If I understand it correctly CheckedC woods as an extension to the language, so you need CheckedC compiler to actually use it.
I agree that SAL fits my description. Is it available outside of Windows? I've seen that someone wanted to add SAL support to clang [0], but decided against, because of Microsoft's patent on the thing [1]. Or than that it looks cool. Thanks for the pointer.
https://www.microsoft.com/en-us/research/project/checked-c/
Microsoft's SAL introduced with their major security rewrite in XP, provides the annotations you mention.
https://docs.microsoft.com/en-us/previous-versions/visualstu...
https://msdn.microsoft.com/en-us/library/windows/desktop/cc3...
But it all boils down to C developers actually caring about using them.