On Fri, May 25, 2007 at 08:29:11AM -0700, Linus Torvalds wrote: > > > On Fri, 25 May 2007, Al Viro wrote: > > > > What did you want that check in evaluate_compare() to catch? Is that > > about warning on explicit comparison with NULL? > > Yes. It was explicitly meant to be a "anybody who tests this pointer > missed the 'safe' part of it". > > But I never used it, so it was really meant as a concept thing, and I > don't think it's wrong to test against non-null. OK... Pointer comparisons care about null pointer constants anyway (BTW, ordered comparison with NULL should give a warning - it's not a valid C and it makes no sense whatsoever even as an extension), so that's not a problem. Other places that care are ?:, simple assignment when target is a pointer, passing arguments to function with prototype when parameter type is a pointer (same logics as with assignment) and cast adding address space (valid for NULL, not valid for random void *). AFAICS, that covers everything; definitely all contexts where null pointer constants are recognized by C and I think that it covers all places where they matter for sparse extensions... - To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
