On Wed, Nov 10, 2010 at 17:07 +0100, Julia Lawall wrote: > > > > But it is impossible to differ wrong type passing to memset: > > > > > > > > struct X *ll; > > > > memset(ll, 0, sizeof(*ll)); > > > > > > > > vs. > > > > > > > > struct X *ll; /* l + l */ > > > > struct Y *l1; /* l + 1 (number one) */ > > > > memset(ll, 0, sizeof(*l1)); > > > > > > OK, I guess. But perhaps the above code would be wrong even if both ll > > > and l1 had type struct X *? > > > > OK, assume that ll is initialized :) > > I still don't get the point.
This code should memset struct by pointer to the struct with invalid size (not the size of the ll struct, but any other wrong size). If cocci knows the argument of sizeof() then it is able to detect this mistake. Also IIRC I saw script in your samples like this one: @@ type T; T x; expression E; @@ -memset(x, E, sizeof(T)); +memset(x, E, sizeof(*T)); This change will break this script. -- Vasiliy _______________________________________________ Cocci mailing list [email protected] http://lists.diku.dk/mailman/listinfo/cocci (Web access from inside DIKUs LAN only)
