Horton

Re: Annoying build warnings from latest Apple toolchain

Andres Freund <andres@anarazel.de>

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From: Andres Freund <andres@anarazel.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Noah Misch <noah@leadboat.com>, pgsql-hackers@lists.postgresql.org
Date: 2023-10-05T17:31:47Z
Lists: pgsql-hackers 
Hi,

On 2023-10-05 13:17:25 -0400, Tom Lane wrote:
> I wrote:
> > So I experimented with fixing things so that the versions of these
> > functions exported by libpq have physically different names from those
> > that you'd get from linking to libpgcommon.a or libpgcommon_srv.a.
> > Then, there's certainty about which one a given usage will link to,
> > based on what the #define environment is when the call is compiled.

I think that's a good plan. IIRC I previously complained about the symbols
existing in multiple places...  Don't remember the details, IIRCI I saw
warnings about symbol conflicts in extensions using libpq.


> > This leads to a pleasingly small patch, at least in the Makefile
> > universe (I've not attempted to sync the meson or MSVC infrastructure
> > with this yet).
> 
> Here's a v2 that addresses the meson infrastructure as well.
> (This is my first attempt at writing meson code, so feel free
> to critique.)  I propose not bothering to fix src/tools/msvc/,
> on the grounds that (a) that infrastructure will likely be gone
> before v17 ships, and (b) the latent problem with version
> skew between libpq.dll and calling programs seems much less
> likely to matter in the Windows world in the first place.

Makes sense.


> +# Note: it's important that we link to encnames.o from libpgcommon, not
> +# from libpq, else we have risks of version skew if we run with a libpq
> +# shared library from a different PG version.  Define
> +# USE_PRIVATE_ENCODING_FUNCS to ensure that that happens.
> +c_args = default_bin_args.get('c_args', []) + ['-DUSE_PRIVATE_ENCODING_FUNCS']
> +
>  initdb = executable('initdb',
>    initdb_sources,
>    include_directories: [timezone_inc],
>    dependencies: [frontend_code, libpq, icu, icu_i18n],
> -  kwargs: default_bin_args,
> +  kwargs: default_bin_args + {
> +    'c_args': c_args,
> +  },

I think you can just pass c_args directly to executable() here, I think adding
c_args to default_bin_args would be a bad idea.

Greetings,

Andres Freund

Commits

  1. meson: macos: Avoid warnings on Sonoma

  2. Restore proper linkage of pg_char_to_encoding() and friends.

  3. meson: macos: Correct -exported_symbols_list syntax for Sonoma compat

  4. Suppress macOS warnings about duplicate libraries in link commands.

  5. Stop using "-multiply_defined suppress" on macOS.

  6. Fix the inadvertent libpq ABI breakage discovered by Martin Pitt: the

  7. Cause libpq and ecpg libraries to be built as proper shared libraries