RFR(XS): 8098517: Unprotected PrintMalloc in os::realloc

[Vitaly Davidovich]

Understood, although having os::free do tty NULL checks for MallocCatchPtr
is confusing then.  Also, not sure a SEGV on printing is the best way to
trap that - why not crash intentionally then or print to stderr? But
perhaps that's a separate issue.

sent from my phone
On Jun 15, 2015 7:47 AM, "David Holmes" <david.holmes at oracle.com> wrote:

> On 15/06/2015 8:44 PM, Vitaly Davidovich wrote:
>
>> Hi Kim,
>>
>> Would it make sense to guard the other couple of tty uses in this method
>> as well? Similar to os::free there.
>>
>
> The "unguarded" ones are all "guarded" by conditions of the form:
>
> if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
>
> and would only trigger upon memory corruption, and then only have an issue
> with a null tty if the corruption is very early in the initialization
> sequence - which seems a very low likelihood and one for which a SEGV would
> not be that bad a thing. Whereas the PrintMalloc uses are unconditional and
> probably do happen before tty has been initialized.
>
> So adding the NULL check would be harmless but also not particularly
> useful, in my opinion.
>
> Cheers,
> David
>
>  sent from my phone
>>
>> On Jun 15, 2015 1:47 AM, "Kim Barrett" <kim.barrett at oracle.com
>> <mailto:kim.barrett at oracle.com>> wrote:
>>
>>     On Jun 14, 2015, at 10:41 PM, David Holmes <david.holmes at oracle.com
>>     <mailto:david.holmes at oracle.com>> wrote:
>>      >
>>      > Looks good and trivial - feel free to push.
>>
>>     Thanks.
>>
>>