Hi Tom,
> If you can show me rewrites of all the basic arithmetic operations that
> detect overflow in full compliance with the C standard, and are
> readable, portable, and efficient, I'm all ears.
These are the best ones that I know of:
https://www.securecoding.cert.org/confluence/display/seccode/INT32-C.+Ensure+that+operations+on+signed+integers+do+not+result+in+overflow
Even if you dislike these, please take a look at the safety checks for
shifts. The current postgresql shift functions need to be strengthened,
and it is easy to do.
John Regehr