Re: BUG #5416: int4inc() is wrong - Mailing list pgsql-bugs

John Regehr wrote:
> 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.

Added to TODO:

    Consider improving overflow detection

        * http://archives.postgresql.org/message-id/4BC66A57.2030809@cs.utah.edu

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + None of us is going to be here forever. +