[cfe-dev] null pointer warning

[Chris Lattner]

On Jul 5, 2010, at 1:35 PM, John McCall wrote:

> On Jul 5, 2010, at 12:20 PM, Chris Lattner wrote:
>> Is there a better place to slot this into Sema?  I didn't follow the warning work John did, but it seems like it must have had to solve similar problems.
> 
> CheckImplicitConversions triggers on a full-expression and walks the entire expression tree, but it does so for much better reasons.  I think what you really want to do is to hook the lvalue-to-rvalue conversion;  I'm not sure if there's a single point where that happens, though.
> 
> Presumably you also want to not warn on
>  int &ref = *(int*) 0;
> ?

After discussion, it turns out that this is a lot harder than it should be.  Instead of handling the general case, I just ended up doing a syntactic check in r107756.  The static analyzer already handles the more complex cases in a far more general way, let it do its job :)

Thanks John,

-Chris