rustc SIGILL since qsort_r patches

[Adhemerval Zanella Netto]

On 07/11/23 08:09, Florian Weimer wrote:
> * Adhemerval Zanella Netto:
> 
>> Just a side note that the quicksort implementation was also used for
>> size (number of elements times size per element) larger than the
>> installed system RAM (_SC_PHYS_PAGES / size > _SC_PAGESIZE) or
>> whether malloc fails.  So it is a latent issue, that did not trigger
>> before by chance.  
> 
> Is it ever beneficial to call the comparison function with identical
> pointers, though?

Afaik this how introsort works, and I am not aware of any comparison
sort with O(1) worst-case space complexity that does not require
a comparison callback that work as <=>.

> 
> This change is going to have annoying consequences for backwards
> compatibility.
> 
> Thanks,
> Florian
>