Re: Clang UndefinedBehaviorSanitize (Postgres14) Detected undefined-behavior

Peter Geoghegan <pg@bowt.ie> writes:
> On Thu, Sep 3, 2020 at 7:53 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I'd still leave -fdelete-null-pointer-checks
>> enabled, because it can make valid and useful optimizations in
>> other cases.

> Is there any evidence that that's true? I wouldn't assume that the gcc
> people exercised good judgement here.

I have not actually dug for examples, but the sort of situation where
I think it would help us is that macros or static inlines could contain
null tests that can be proven useless at particular call sites due to
surrounding code.

            regards, tom lane