Horton

Re: Tree-walker callbacks vs -Wdeprecated-non-prototype

Thomas Munro <thomas.munro@gmail.com>

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From: Thomas Munro <thomas.munro@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2022-09-19T07:40:11Z
Lists: pgsql-hackers 
On Mon, Sep 19, 2022 at 10:16 AM Thomas Munro <thomas.munro@gmail.com> wrote:
> On Mon, Sep 19, 2022 at 8:57 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > BTW, I was distressed to discover that someone decided they could
> > use ExecShutdownNode as a planstate_tree_walker() walker even though
> > its argument list is not even the right length.  I'm a bit flabbergasted
> > that we seem to have gotten away with that so far, because I'd have
> > thought for sure that it'd break some platform's convention for which
> > argument gets passed where.  I think we need to fix that, independently
> > of what we do about the larger scope of these problems.  To avoid an
> > API break, I propose making ExecShutdownNode just be a one-liner that
> > calls an internal ExecShutdownNode_walker() function.  (I've not done
> > it that way in the attached, though.)
>
> Huh... wouldn't systems that pass arguments right-to-left on the stack
> receive NULL for node?  That'd include the SysV i386 convention used
> on Linux, *BSD etc.  But that can't be right or we'd know about it...

I take that back after looking up some long forgotten details; it
happily ignores extra arguments.

Commits

  1. Remove accidentally added meson.build

  2. Disable clang 16's -Wcast-function-type-strict.

  3. Disable -Wdeprecated-non-prototype in the back branches.

  4. Revise tree-walk APIs to improve spec compliance & silence warnings.

  5. Future-proof the recursion inside ExecShutdownNode().