Re: [RFC] building postgres with meson

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Thomas Munro <thomas.munro@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2021-11-15T22:46:49Z
Lists: pgsql-hackers
Hi,

On 2021-11-15 17:34:33 -0500, Tom Lane wrote:
> Thomas Munro <thomas.munro@gmail.com> writes:
> > ... The interesting thing about 16.1 is that you can invoke it
> > as xlclang to get the new clang frontend and, I think, possibly use
> > more clang/gcc-ish compiler switches[2].
> > [2] https://www.ibm.com/docs/en/xl-c-and-cpp-aix/16.1?topic=new-clang-based-front-end
>
> Ho, that's an earful ;-).  Though I wonder whether that frontend
> hides the AIX-specific linking issues you mentioned.  (Also, although
> I see /opt/IBM/xlc/16.1.0/ on gcc119, there's no xlclang there.
> So whether we have useful access to it right now is unclear.)

It's actually available there, but in /opt/IBM/xlC/16.1.0/bin/xlclang++ (note
the upper case C).

It doesn't really hide the linking issues afaict. I think they're basically an
ABI rather than a linker invocation issue. It's not that hard to address them
though, it's basically making mkldexport.sh a tiny bit more general and
integrating it into src/backend/postgres' build.

We don't have to generate export files for shared libraries anymore though,
afaict, because there's 'expall', which suffices for our purposes. dlopen()
doesn't require an import file.


> This plays into something that was nagging at me while I wrote my
> upthread screed about not giving up on non-gcc/clang compilers:
> are those compilers outcompeting all the proprietary ones, to the
> extent that the latter will be dead soon anyway?

I think that's a pretty clear trend. The ones that aren't dying seem to be
incrementally onto more and more rebasing onto llvm tooling.

It doesn't help that most of those compilers are primarily for OSs that, uh,
aren't exactly growing. Which limits their potential usability significantly.

Greetings,

Andres Freund



Commits

  1. meson: Add 'running' test setup, as a replacement for installcheck

  2. meson: Add support for building with precompiled headers

  3. windows: Adjust FD_SETSIZE via commandline define

  4. meson: docs: Add xml{lint,proc} wrapper to collect dependencies

  5. meson: ecpg: Split definition of static and shared libraries

  6. windows: Set UMDF_USING_NTSTATUS globally, include ntstatus.h

  7. ci: Add hint about downloadable logs to README

  8. meson: Set up absolute rpaths to libdir

  9. meson: Include CFLAGS/c_args in summary and pg_config output

  10. windows: remove date from version number in win32ver.rc

  11. meson: Add initial version of meson based build system

  12. ci: windows: set error mode to not include SEM_NOGPFAULTERRORBOX

  13. Refactor PG_TEST_EXTRA logic in autoconf build

  14. Split TESTDIR into TESTLOGDIR and TESTDATADIR

  15. Don't hardcode tmp_check/ as test directory for tap tests

  16. Extend gendef.pl in preparation for meson

  17. Include c.h instead of postgres.h in src/port/*p{read,write}*.c

  18. Remove DLLTOOL, DLLWRAP from configure / Makefile.global.in

  19. Run xmllint validation only once

  20. Bump minimum Perl version to 5.14

  21. Move gramparse.h to src/backend/parser

  22. Run perltidy over Catalog.pm

  23. Parse catalog .dat files as a whole when compiling the backend

  24. Build all Flex files standalone

  25. Move private declarations shared between guc.c and guc-file.l to new header

  26. Preparatory refactoring for compiling guc-file.c standalone

  27. Move darwin sysroot determination into separate file

  28. Fix MSVC warning in compat_informix/rnull.pgc

  29. solaris: Use versioning scripts instead of -Bsymbolic

  30. Change shared library installation naming on macOS

  31. regress: allow to specify directory containing expected files, for ecpg

  32. Don't add HAVE_LDAP_H HAVE_WINLDAP_H to pg_config.h

  33. Refactor dtrace postprocessing make rules

  34. Add output directory option to gen_node_support.pl

  35. Add output directory argument to generate-unicode_norm_table.pl

  36. Add output file argument to generate-errcodes.pl

  37. Add output path arg in generate-lwlocknames.pl

  38. Move snowball_create.sql creation into perl file

  39. ecpg: Output dir, source dir, stamp file argument for preproc/*.pl

  40. psql: Output dir and dependency generation for sql_help

  41. Deal with paths containing \ and spaces in basebackup_to_shell tests

  42. Remove LLVM_CONFIG from Makefile.global.in

  43. Make update-unicode target work in vpath builds

  44. Refactor DLSUFFIX handling

  45. ldap tests: Add paths for openbsd.

  46. ldap tests: Don't run on unsupported operating systems.

  47. Remove check for accept() argument types

  48. Move our p{read,write}v replacements into their own files.

  49. Adjust yywrap macro for non-reentrant scanners for MSVC.

  50. Remove any -arch switches given in ExtUtils::Embed's ldopts from our

  51. Change PL/Perl and Pg interface build to use configured compiler and

  52. Apparently, on some systems, ExtUtils::Embed and MakeMaker are slightly