Re: [PATCH] globsort: handle int overflow in cmp functions

[Chet Ramey]

On 5/17/24 12:57 PM, Grisha Levit wrote:
> The current cmp implementation for size and blocks subtracts the two
> values and returns the difference as an int. This subtraction can
> overflow, and the returned int can end up having the wrong sign.
>
> This also makes the qsort comparison function non-transitive. (Some
> interesting discussion on that at [1]).

Thanks for the report. If overflow is a concern, then a guaranteed
transitive comparison function is the right thing. Your solution is clever,
but a little obscure; I think I'll make it look more like the other
comparison functions.

Chet

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/

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