Date: Sun, 9 Jan 2022 08:48:54 -0800
From: Noah Misch <noah@leadboat.com>
To: Tom Lane <tgl@sss.pgh.pa.us>, Zhihong Yu <zyu@yugabyte.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: null iv parameter passed to combo_init()
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On Sun, Jan 09, 2022 at 04:37:32AM -0800, Zhihong Yu wrote:
> On Sat, Jan 8, 2022 at 11:32 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > Noah Misch <noah@leadboat.com> writes:
> > > On further thought, I would write it this way:
> >
> > > -             else
> > > +             else if (ivlen != 0)
> > >                       memcpy(ivbuf, iv, ivlen);
> >
> > FWIW, I liked the "ivlen > 0" formulation better.  They should be
> > equivalent, because ivlen is unsigned, but it just seems like "> 0"
> > is more natural.

If I were considering the one code site in isolation, I'd pick "ivlen > 0".
But of the four sites identified so far, three have signed length variables.
Since we're likely to get more examples of this pattern, some signed and some
unsigned, I'd rather use a style that does the optimal thing whether or not
the variable is signed.  What do you think?

> Patch v4 is attached.

Does this pass the test procedure shown upthread?