Possible subtle memory model error in ClassValue

Andrew Dinn adinn at redhat.com
Tue Aug 11 11:03:35 UTC 2020

On 11/08/2020 11:47, Andrew Haley wrote:
> On 09/08/2020 18:55, Hans Boehm wrote:
>> There is no guarantee that the address dependency enforces ordering
>> if there is no final field involved. This may matter in the future,
>> since ARM's Scalable Vector Extension does not guarantee ordering
>> for address-dependent loads, if both loads are vector loads.
> Ouch. Thanks, I didn't know that.

You ought to look at the pdf Ningsheng linked in the RFR that was posted
with the SVE patch. The pdf is available here:


The relevant text is in section 4.4. Memory Ordering.


Andrew Dinn
Red Hat Distinguished Engineer
Red Hat UK Ltd
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