On Wed, Jun 12, 2024, at 10:55 AM, Paul Eggert wrote:

A lot of this stuff is pedanticism that dates back to the bad old days
when the C standard allowed ones' complement and signed magnitude
representations of signed integers. Although it can be amusing to
worry about that possibility (I know I've done it) it's never been a
practical worry, and even the motivation of pedanticism is going away
now that C23 requires two's complement.

Unless C23 eliminated *all* the cases where an operation on unsigned
integers is well-defined but the same operation on signed integers is
undefined, and last I checked it had not, there is still a need for
caution around conversions that change signedness.

zw