On Fri, Aug 12, 2011 at 10:47:11AM -0700, Christopher Li wrote: > On Thu, Aug 11, 2011 at 10:14 AM, Ben Pfaff <blp@xxxxxxxxxxxxxxx> wrote: > > What is the intended use of the sparse "safe" attribute? I do > > not see any uses of it in Linux (although there is a __safe macro > > for it). I don't see any documentation for it either. > > I don't know much about the safe attribute either. I find out the > commit which introduce the safe attribute by "git blame". > > If a pointer is never NULL, there is not need to test the pointer. > > Chris > > commit 98f14350c26518f0f5c45632d145a218d468d8b8 > Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx> > Date: Fri Apr 16 18:19:30 2004 -0700 > > Introduce "safe" pointer expressions. > > These are defined to never be NULL or nontrapping, and could > help code generation, but right now only cause a warning if > they are tested in a conditional. That does actually seem useful. The Linux kernel has various structures with pointers that should never be NULL, and documenting that in a compiler-visible way seems like a feature. - Josh Triplett -- 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
