Horton

Re: pgsql: Provide overflow safe integer math inline functions.

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Paquier <michael.paquier@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, pgsql-committers@postgresql.org
Date: 2017-12-17T16:03:49Z
Lists: pgsql-hackers 
Michael Paquier <michael.paquier@gmail.com> writes:
> ... Please note that if you added
> a volatile cast to "result" as well, then compilation was able to
> complete and regression tests passed...

Yeah, that squares with my analysis: the problem with the existing test
is that the compiler is throwing away the function call because its
output is unused.

If I haven't seen something from Andres shortly, I'll push a fix.

			regards, tom lane

Commits

  1. Try harder to detect unavailability of __builtin_mul_overflow(int64).

  2. Try to detect runtime unavailability of __builtin_mul_overflow(int64).

  3. Fix a number of copy & paste comment errors in common/int.h.

  4. Provide overflow safe integer math inline functions.