Re: memory barriers (was: Yes, WaitLatch is vulnerable to weak-memory-ordering bugs)

On Wed, Sep 21, 2011 at 4:19 PM, Gurjeet Singh <singh(dot)gurjeet(at)gmail(dot)com> wrote:
> On Wed, Sep 14, 2011 at 4:29 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>>
>> On Mon, Aug 8, 2011 at 7:47 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> > I've been thinking about this too and actually went so far as to do
>> > some research and put together something that I hope covers most of
>> > the interesting cases.  The attached patch is pretty much entirely
>> > untested, but reflects my present belief about how things ought to
>> > work.
>>
>> And, here's an updated version, with some of the more obviously broken
>> things fixed.
>
> You declare dummy_spinlock variable as extren and use it, but it is not
> defined anywhere. Wouldn't that be a linker error?

Yeah, we need to add that somewhere, maybe s_lock.c

--
Robert Haas
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