[PATCH 2/2] staging: emxx_udc: test returned value

[Dan Carpenter]

On Sat, Apr 04, 2015 at 06:20:53PM +0200, Julia Lawall wrote:
> Couldn't one say:
> 
> x = NULL;
> y = &x->whatever;
> z = container_of(y, struct blah, whatever);
> 
> and end up with z being NULL?

That is crazy person code.  It looks deliberately wrong.  If we start
merging deliberate mistakes then we're already screwed.

I have a smatch check which warns on container_of() but I should update
it to not complain if it's the first struct member.  I have looked at
quite a few of these warnings and I worry that there are some places
where it relies on container_of() to be a no-op...  That's also crazy
but it's the kind of crazy that people do in real life.  :P

regards,
dan carpenter