Re: Suspicion of a compiler bug in clang: using ternary operator in ereport()

On 2014-01-28 18:31:59 -0300, Alvaro Herrera wrote:
> Jason Petersen wrote:
> > I realize Postgres’ codebase is probably intractably large to begin
> > using a tool like splint (http://www.splint.org ), but this is exactly
> > the sort of thing it’ll catch. I’m pretty sure it would have warned in
> > this case that the code relies on an ordering of side effects that is
> > left undefined by C standards (and as seen here implemented
> > differently by two different compilers).
>
> Well, we already have Coverity reports and the VIVA64 stuff posted last
> month. Did they not see these problems? Maybe they did, maybe not, but
> since there's a large number of false positives it's hard to tell. I
> don't know how many false positives we would get from a Splint run, but
> my guess is that it'll be a lot.

Well, this isn't really a case of classical undefined beaviour. Most of
the code is actually perfectly well setup to handle the differing
evaluation, it's just that some bits of code forgot to restore errno.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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