Put NULL test on the result of the previous call instead on one of its arguments. The complete semantic match that finds these problems is as follows (http://coccinelle.lip6.fr/): // <smpl> @r@ expression *e1; expression *e2; identifier f; statement S1,S2; position p,p2; @@ e1 = f@p(...,e2,...); ( if (e1 == NULL || ...) S1 else S2 | if (e1 != NULL || ...) S1 else S2 | if@p2 (e2 == NULL || ...) S1 else S2 | if@p2 (e2 != NULL || ...) S1 else S2 ) @ok@ expression e1,e2; identifier f; statement S1,S2; position r.p,r.p2; @@ e1 = f@p(...); ( if@p2 (e2 == NULL || ...) S1 else S2 | if@p2 (e2 != NULL || ...) S1 else S2 ) @ok1 depends on ok exists@ position r.p; expression *r.e2; expression e3; identifier f,g; @@ e2->g ... when != e2 = e3 when != &e2 f@p @ok2 depends on ok exists@ position r.p; expression *r.e2; expression e,e3; statement S1,S2; identifier f; @@ ( if (e2 == NULL || ...) {... return ...;} else S2 | if (e2 != NULL || ...) S1 else {... return ...;} ) ... when != e2 = e3 when != &e2 e = f@p(...); @depends on ok1 || ok2@ expression e1; identifier f; position r.p; @@ * e1 = f@p(...); // </smpl> -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
