On Wed, Jun 27, 2007 at 10:45:55AM -0700, Linus Torvalds wrote: > > > On Wed, 27 Jun 2007, Al Viro wrote: > > > > Eh... I'd say that my variant for offsetof() is simply better - it usually > > directly turns into EXPR_VALUE, right in place, without rather convoluted > > work. Aside of "should such cast be a constant integer expression"... > > Umm. But sparse is meant to parse C code. Which very much includes *other* > projects. > > The kernel, for example, has its own offsetof. And yes, these days we use > "__compiler_offsetof()", but we used to do > > #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) > > and I seriously doubt that the kernel is the only one doing things like > that. You can't have it both way, really. If we are talking about annotating a codebase we _can_ annotate, that one is not a problem at all. If we are talking about vanilla C project that never heard about sparse... We can define whatever extensions we like, but such project has to cope with whatever C compilers they had been using. So "sparse believes that this defintion of offsetof can be used as array size" will mean fsck-all outside of #ifdef __CHECKER__ and under such ifdef we can always define it to builtin; if anything, that will be faster and easier on sparse. - 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
