On Mon, 1 Aug 2016, SF Markus Elfring wrote:
> >> How do you think about the following SmPL script example? > >> > >> @vz_combined > >> depends on patch && !context && !org && !report@ > >> type T; > >> T* pointer; > >> +statement S; > >> expression express; > >> @@ > >> pointer = > >> - vmalloc > >> + vzalloc > >> (...); > >> if (!d) > >> S > >> -memset(d, 0, sizeof( > >> ( > >> -T > >> | > >> -*(express) > >> ) > >> -)); Actually, this is a mess. pointer, d, and express are all supposed to be the same thing, as they were in the original rule. Furthermore, this shows a reason why the original rule was better. If you say T *pointer, then you require that Coccinelle can find the type sofficiently to know that it is a pointer. There was no such constraint in the sizeof(*d) variant of the original rule. > > The performance issue is that disjunctions on expressions, eg (A | B), are > > implemented as (A | (!A & B)), ie with a negation of all the previous > > options &d with each option. So it is better to avoid very large > > disjunctions on expressions. > > Is the suggested SmPL disjunction still small enough for this concern? 2 elements is OK. julia
