Re: [RFC] building postgres with meson

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: pgsql-hackers@postgresql.org, Andrew Dunstan <andrew@dunslane.net>, Magnus Hagander <magnus@hagander.net>
Date: 2022-08-09T07:10:55Z
Lists: pgsql-hackers
Hi,

I was looking at re-unifying gendef2.pl that the meson patchset had introduced
for temporary ease during hacking with gendef.pl. Testing that I noticed that
either I and my machine is very confused, or gendef.pl's check whether it can
skip work is bogus.

I noticed that, despite having code to avoid rerunning when the input files
are older than the .def file, it always runs.

# if the def file exists and is newer than all input object files, skip
# its creation
if (-f $deffile
    && (-M $deffile > max(map { -M } <$ARGV[0]/*.obj>)))
{
    print "Not re-generating $defname.DEF, file already exists.\n";
    exit(0);
}

My understanding of -M is that it returns the time delta between the file
modification and the start of the script. Which makes the use of max() bogus,
since it'll return the oldest time any input has been modified, not the
newest. And the condition needs to be inverted, because we want to skip the
work if $deffile is *newer*, right?

Am I missing something here?


I'm tempted to just remove the not-regenerating logic - gendef.pl shouldn't
run if there's nothing to do, and it'll e.g. not notice if there's an
additional input that wasn't there during the last invocation of gendef.pl.

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