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)