Re: Possible NULL pointer dereference in GCC's vec code?

[Jeff Law <law at redhat dot com>]

On 02/11/13 16:46, Ian Lance Taylor wrote:
> But those cases are passing 1 to vec_safe_reserve, which in turn
> passes 1 to calculate_allocation, so calculate_allocation can not
> return 0, so vec_reserve can not return NULL.
>
> At least that is how it seems to me.
Yes, you're right.  I got too deep into looking at just what was visible 
in the preprocessed code (c-common I think) and didn't look at 
calculate_allocation from vec.c.

So this a false positive for my null pointer dereference checker. 
There's nothing to propagate the fact that calculate_allocation can not 
return null if reserve is > 0.

This is also a good example of code which can be improved by isolating 
the unexecutable paths where the calls to vec_safe_reserve return NULL.

Thanks for the sanity check...

Jeff