RFR(XS): 8009287 Uninitialised variable in hotspot/agent/src/os/linux/ps_core.c

[Dean Long]

On 3/5/2013 4:48 PM, David Holmes wrote:
> On 6/03/2013 10:44 AM, Dean Long wrote:
>> On 3/5/2013 3:23 PM, David Holmes wrote:
>>> On 6/03/2013 9:08 AM, Dean Long wrote:
>>>> What if allocate_init_map() fails to allocate memory?  Shouldn't
>>>> add_class_share_map_info() follow the pattern of add_map_info():
>>>> return NULL or "map", and have the caller check for NULL?
>>>
>>> AFAICS apart from one seeming bug, if we can't allocate a new map it
>>> does no harm in terms of the code that looks at the map. The bug is:
>>>
>>>  177    mp = ph->core->class_share_maps;
>>>  178    if (mp) {
>>>  179       print_debug("can't locate map_info at 0x%lx, trying class
>>> share maps\n",
>>>  180              addr);
>>>
>>> where I think 178 should be "if (mp==NULL)". Everything else will just
>>> do nothing upon encountering a NULL map.
>>>
>>> The fix addresses the parfait warning and leaves the code functionally
>>> unchanged. So any robustness issues would need to be done via a follow
>>> up RFE.
>>>
>> Why not just add "return map" at the end of the function?  It seems
>> closer to the intent of the original code, assuming it
>> addresses the parfait warning.
>
> Nothing expects a return value from that function so what point is 
> there in returning something? I would expect that to simply produce 
> another warning/error about a function return value being ignored.
>
If it complains about that then wouldn't we need to put (void) in front 
of all calls to strcat(), for example?
Anyway, I'm OK with the current change if Staffan files an RFE for other 
issue.

dl

> David
> -----
>
>>
>> dl
>>
>>> David
>>>
>>>> dl
>>>>
>>>> On 3/4/2013 11:39 PM, David Holmes wrote:
>>>>> Looks fine to me - thanks Staffan!
>>>>>
>>>>> David
>>>>>
>>>>> On 5/03/2013 5:24 PM, Staffan Larsen wrote:
>>>>>> A very small fix for a warning.
>>>>>>
>>>>>> webrev: http://cr.openjdk.java.net/~sla/8009287/webrev.00/
>>>>>>
>>>>>> Thanks,
>>>>>> /Staffan
>>>>>>
>>>>
>>