HELLO ? Anyone interested ?

[Marc Espie]

I can understand not having complete comments on the full patch, but
so far, I haven't even heard whether what I was doing looked sensible
or not...

I'd like at least some basic feedback on the concept.

I've had some request from David Howells (who seems to be having email
trouble, BTW...) to add something similar to check calls such as
void XtVaSetValues(Widget w, ...)
where the last argument of the function _must_ be NULL.

I believe I can implement an attribute sentinel on top of my
__nonnull__ patch to handle these kind of function, but it's worthless
if nobody agrees on the basic idea *first*.