[PATCH v3 3/8] malloc: Basic support for memory tagging in the malloc() family

[Richard Earnshaw]

On 25/11/2020 14:58, Florian Weimer via Libc-alpha wrote:
> * Richard Earnshaw via Libc-alpha:
> 
>> +/* Set the tags for a region of memory, which must have size and alignment
>> +   that are multiples of __MTAG_GRANULE_SIZE.  Size cannot be zero.
>> +   void *__libc_mtag_tag_region (const void *, size_t)  */
>> +#define __libc_mtag_tag_region(p, s) (p)
> 
> I think we need a description of how the tagging operation is supposed
> to work.  For example, it's surprising that the requested tag is not
> specified in an argument.
> 
> Thanks,
> Florian
> 

The (new) tag is already encoded in the pointer.  It's (obviously)
implementation specific how that is done.  I'll clarify the comment.

R.