[PATCH 0/7] RFC Memory tagging support

Richard Earnshaw (lists) Richard.Earnshaw@arm.com
Mon Jun 15 18:14:05 GMT 2020

On 15/06/2020 19:05, Paul Eggert wrote:
> On 6/15/20 9:51 AM, Richard Earnshaw (lists) wrote:
>> In practice it will work because objects passed to memmove will have to
>> have a single colour,
> Does this mean all stack and heap objects visible to the C programmer must have
> the same tag? This surprises me, as I thought part of the idea was to assign
> tags randomly.

No, I mean that a single block of memory must have a single tag, so if
the regions overlap, they must have the same tag.  If they don't
overlap, then the tags can be different, but then the length check would
indicate that as well.

memcpy/memmove aren't expected to copy the tag, since you might be
copying some data into the middle of another block.  All hell would
likely break out if they tried to do that.


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