On Mon, 2016-03-14 at 21:43 +0100, Julia Lawall wrote: > On Mon, 14 Mar 2016, Joe Perches wrote: > > I wrote a little cocci script to remove unnecessary > > casts for memset and memcpy (below) and tested it on > > linux kernel's drivers/staging/ directory. > > > > For instance, when dst and src are already pointers: > > > > - memcpy((u8 *)dst, (u8 *)src, r8712_get_wlan_bssid_ex_sz(src)); > > + memcpy(dst, src, r8712_get_wlan_bssid_ex_sz(src)); > > > > It works ok, (it doesn't remove unnecessary parentheses > > around the pointers) but it makes me wonder if there's a > > generalized spatch mechanism to remove casts when an > > arbitrary function takes a void * in any argument > > position and a call to that function uses a cast of a > > pointer to any pointer type for that argument. > > > > $ cat remove_mem_casts.cocci > > @@ > > type t; > > t *p; > > type v; > > expression e1; > > expression e2; > > @@ > > > > - memset((v*)p, e1, e2) > > + memset(p, e1, e2) > > > > @@ > > type t; > > t *p; > > type v; > > expression e1; > > expression e2; > > @@ > > > > - memcpy((v*)p, e1, e2) > > + memcpy(p, e1, e2) > > > > @@ > > type t; > > t *p; > > type v; > > expression e1; > > expression e2; > > @@ > > > > - memcpy(e1, (v*)p, e2) > > + memcpy(e1, p, e2) > > > > @@ > > type t1; > > type t2; > > t1 *p1; > > t2 *p2; > > type v1; > > type v2; > > expression e1; > > @@ > > > > - memcpy((v1*)p1, (v2*)p2, e1) > > + memcpy(p1, p2, e1) > > This should do everything: > > @@ > identifier f; > expression *e; > type T; > @@ > > f(..., > - (T *)( > e > - ) > ,...) > > @@ > identifier f; > expression *e; > type T; > @@ > > f(..., > - (T *) > e > ,...) > > julia Hi Julia, I think your proposed script is not correct. The function must take a void * argument. There's no validation of that here. cheers, Joe -- 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
