[Skiboot] [PATCH] core: Fix backtrace for gcc 6

[Vasant Hegde]

On 03/01/2016 08:51 AM, Joel Stanley wrote:
> On Mon, Feb 29, 2016 at 3:56 PM, Vasant Hegde
> <hegdevasant at linux.vnet.ibm.com> wrote:
>>> -       unsigned long *fp = __builtin_frame_address(1);
>>> +       unsigned long *fp = __builtin_frame_address(0);
>>>
>>>          *count = 0;
>>>          while(room) {
>>> +               fp = (unsigned long *)fp[0];
>>
>>
>> What if fp is NULL?
>
> We dereference a null pointer.
>
> Will we ever find ourselves in the situation where there is no frame pointer?

Never.  But I doubt code analysis tools  understand that and we may start 
getting warnings ;-)

-Vasant