On Wed, Jun 18, 2025 at 08:33:27PM -0700, Marc Herbert wrote: > > But, again, this is a totally different thing from what the patch does. > > The faux_device_destroy() code is not doing a dereference, it's doing > > pointer math. > > pointer math is what we _want_ the code to do. But if that relies on > some undefined behavior(s) then the bets are off again. Check > https://stackoverflow.com/questions/26906621/does-struct-name-null-b-cause-undefined-behaviour-in-c11 > where offsetof() is a suggested alternative. The answers talk about "But the value of a null pointer constant is not defined as 0." which is some trivia that had heard before. Probably I heard it in the context of someone saying that we should check "if (p == NULL)" instead of "if (!p)"... regards, dan carpenter
