Horton
Menu

Re: Change copyObject() to use typeof_unqual

Jelte Fennema <postgres@jeltef.nl>

View thread
From: "Jelte Fennema-Nio" <postgres@jeltef.nl>
To: "Peter Eisentraut" <peter@eisentraut.org>
Cc: "pgsql-hackers" <pgsql-hackers@postgresql.org>
Date: 2026-03-15T21:54:04Z
Lists: pgsql-hackers

Attachments

On Fri, 13 Mar 2026 at 11:43, Peter Eisentraut <peter@eisentraut.org> wrote:
> There is a failure on buildfarm member taipan because it uses an unusual
> combination of gcc and clang (the gcc is much newer than clang).  The
> only sensible workaround I could think of is a hardcoded override based
> on the clang version, as in the attached patch.  

If we can then start prefering typeof_unqual over __typeof_unqual__ in
the configure check for CC, then I think I like this as a workaround.

If not, then I'm starting to think that actually checking support for
this feature for CLANG is probably easier to understand (and less
fragile) than combining all of these tricks together. Attached is a
patch to do so. 

This only does it for CLANG, not for CLANG compiling C++ files.
Theoretically that could be necessary, but I couldn't find a C++
compiler that supports any spelling of typeof_unqual. So I'm not even
sure we need the current CXX check for typeof_unqual, I think we could
remove that too and always use the fallback.

> And alternative is that
> we decide that we don't want to support this combination, meaning that
> we would effectively require that clang is approximately as-old-or-newer
> than gcc.

Given that Tom seems to have reproduced this on Fedora 40, it sounds
like we should fix it.

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Add some const qualifiers enabled by typeof_unqual change on copyObject

  2. Hardcode typeof_unqual to __typeof_unqual__ for clang

  3. Clean up postgres_fdw/t/010_subscription.pl.

  4. Hardcode override of typeof_unqual for clang-for-bitcode

  5. Make typeof and typeof_unqual fallback definitions work on C++11

  6. Change copyObject() to use typeof_unqual

  7. Fixes for C++ typeof implementation

  8. Support using copyObject in standard C++