patch, 5 partsmiscellaneous build mods (part 2)

This series (part 2) continues the miscellaneous changes to the make, meson and autoconf build systems. I am sending this part a little earlier than I expected, so there will now be a part 3!

The reason for the early posting is to try and avoid an regression in the autoconf build system (see patch #5). Hopefully, we still have time in this cycle to get patch #5 included.

This series is based on commit 6f84262c44 ("The eleventh batch", 2025-05-05)

I did a test merge to 'next'@629a3ecd64 without issue, but 'seen'@71cfd25022 had a small conflict with commit 1a2929c851 ("meson: allow customize perl installation path", 2025-04-24) on the 'dd/meson-perl-custom-path' branch. (I note that a new version of that patch was posted to the list today).

The fixup looks like:

    diff --cc perl/Git/SVN/Memoize/meson.build
    index 4c589b30c3,8c2e80d2d2..d6209dc3bf
    --- a/perl/Git/SVN/Memoize/meson.build
    +++ b/perl/Git/SVN/Memoize/meson.build
    @@@ -3,6 -3,6 +3,6 @@@ test_dependencies += custom_target
        output: 'YAML.pm',
        command: generate_perl_command,
        install: true,
    -   install_dir: perllibdir / 'Git/SVN',
     -  install_dir: get_option('datadir') / 'perl5/Git/SVN/Memoize',
    ++  install_dir: perllibdir / 'Git/SVN/Memoize',
        depends: [git_version_file],
      )

ATB, Ramsay Jones

Ramsay Jones (5):
  meson.build: quote the GITWEBDIR build configuration
  meson: correct install location of YAML.pm
  meson: correct path to system config/attribute files
  meson.build: correct setting of GIT_EXEC_PATH
  configure.ac: upgrade to a compilation check for sysinfo

 configure.ac                     | 25 ++++++++++++++++++++++---
 meson.build                      | 28 +++++++++++++++++++++++-----
 meson_options.txt                |  4 ++--
 perl/Git/SVN/Memoize/meson.build |  2 +-
 4 files changed, 48 insertions(+), 11 deletions(-)

The build configuration options with (non-empty) values, for example filesystem paths potentially containing spaces, have been set using the '.set_quoted()' method. However, the GITWEBDIR value has been set using the '.set()' method instead. In order to correctly quote the GITWEBDIR value, replace the '.set()' method with '.set_quoted()'.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

When executing an 'meson install' the YAML.pm file is incorrectly placed in the <prefix>/share/perl5/Git/SVN directory. The YAML.pm file should be placed in a 'Memoize' subdirectory instead. In order to correct the location, update the 'install_dir' of the relevant target in the 'perl/Git/SVN/Memoize/meson.build' file.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 perl/Git/SVN/Memoize/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

The path to the system-wide config and attributes files are not being set correctly in the meson build. Unless explicitly overridden on the command line during setup, the 'gitconfig' and 'gitattributes' options are defaulting to absolute paths in the '/etc' system directory. This is only appropriate if the <prefix> is set specifically to '/usr'.

The directory in which these files are placed is generally referred to as the 'system configuration directory' or 'sysconfdir' for short. When the prefix is '/usr' then the sysconfdir is usually set to '/etc', but any other value for prefix results in the relative directory value 'etc' instead. (eg if prefix is '/usr/local', then the 'etc' relative value results in a system configuration directory of '/usr/local/etc'). When setting the 'sysconfdir' builtin option value, the meson system uses exactly this algorithm, so we can use get_option('sysconfdir') directly when setting the (non-overridden) build variables.

In order to allow for overriding from the command line, remove the default values specified for the 'gitconfig' and 'gitattributes' options in the 'meson_options.txt' file. This allows the user to specify any pathname for those options, while being able to test for the unset (empty) value. An absolute pathname will be used unchanged and a relative pathname will be appended to '<prefix>/'. These values are then used to set the 'ETC_GITCONFIG' and 'ETC_GITATTRIBUTES' build variables which are, in turn, passed to the compiler as '-D' arguments.

When the 'gitconfig' or 'gitattributes' options are not used, then use the built-in 'sysconfdir' and set the ETC_GITCONFIG build variable to the string "<sysconfdir>/gitconfig". Similarly, set ETC_ATTRIBUTES to "<sysconfdir>/gitattributes".

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build       | 14 ++++++++++++--
 meson_options.txt |  4 ++--
 2 files changed, 14 insertions(+), 4 deletions(-)

For the non-'runtime prefix' case, the meson build sets the GIT_EXEC_PATH build variable to an absolute path equivalent to <prefix>/libexec/git-core. In comparison, the default make build sets it to a relative path equivalent to 'libexec/git-core'. Indeed, the make build requires the use of some means outside of the Makefile (eg. config.mak[.*] or the command-line) to set GIT_EXEC_PATH to anything other than 'libexec/git-core'.

For example, the make invocation:

  $ make gitexecdir=/some/other/bin all install

will build git with GIT_EXEC_PATH set to '/some/other/bin' and install the 'library' executables to that location. However, without setting the 'gitexecdir' make variable, irrespective of the 'runtime prefix' setting, the GIT_EXEC_PATH is always set to 'libexec/git-core'.

The meson built-in 'libexecdir' option can be used to provide a similar configurability. The default value for the option is 'libexec'. Attempting to set the option to '' on the command-line, will reset it to the '.' string, presumably to ensure a relative path value.

This commit allows the meson build, similar to the above, to configure the project like:

  $ meson setup --buildtype=debugoptimized -Dprefix=$HOME -Dpcre2=disabled \
      -Dlibexecdir=/some/other/bin build

so that the GIT_EXEC_PATH is set to '/some/other/bin'. Absent the -Dlibexecdir argument, the GIT_EXEC_PATH is set to 'libexec/git-core'.

In order to correct the value of GIT_EXEC_PATH, default the value to the static string value 'libexec/git-core', and only override if the value of the 'libexecdir' option has a value different to 'libexec' or '.'. Also, like the Makefile, add a check for an absolute path when the runtime prefix option is true (and if so, error out).

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

Commit f5e3c6c57d ("meson: do a full usage-based compile check for sysinfo", 2025-04-25) updated the 'sysinfo()' check, as part of the meson build, due to the failure of the check on Solaris. Prior to that commit, the meson build only checked the availability of the '<sys/sysinfo.h>' header file. On Solaris, both the header and the 'sysinfo()' function exist, but are completely unrelated to the same function on Linux (and cygwin).

Commit 50dec7c566 ("config.mak.uname: add sysinfo() configuration for cygwin", 2025-04-17) added a similar 'sysinfo()' check to the autoconf build. This check looked for the 'sysinfo()' function itself, rather than just the header, but it will fail (incorrectly set HAVE_SYSINFO) for the same reason.

In order to correctly identify the 'sysinfo()' function we require as part of 'git-gc' (used in the 'total_ram() function), we also upgrade to a compilation check, in a similar way to the meson commit. Note that since commit c9a51775a3 ("builtin/gc.c: correct RAM calculation when using sysinfo", 2025-04-17) both the 'totalram' and 'mem_unit' fields of the 'struct sysinfo' are used, so the new check includes both of those fields in the compile check.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 configure.ac | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

On 5/8/25 12:44 PM, Ramsay Jones wrote:

and

Well, I can confirm this results in the detection being correctly changed on Solaris 11.3 and stop reporting sysinfo as available during ./configure, so this has my ACK on technical grounds. That being said, in the original meson thread, there was this review:

On 4/22/25 3:31 AM, Patrick Steinhardt wrote:

So you are indeed teaching autoconf to check for this function, but should we also ask whether it's worth continued maintenance of autoconf? It was/is not clear to me who the stakeholders are for the autoconf support.

On the one hand, it exists so maybe it should be fixed when we know it has issues.

On the other hand, it sounds like this patch (and commit 50dec7c566 "config.mak.uname: add sysinfo() configuration for cygwin") only modify autoconf out of a sense of duty, rather than finding autoconf useful. What does it say about the autoconf support if the people finding bugs in it don't even use it, but only discovered the bug while working on a different build system they do use and depend on (config.mak.uname, or meson.build, both count here). Who *is* using it? Apparently not Solaris users?

On 08/05/2025 22:07, Eli Schwartz wrote:

[snip]

Thank you very much for testing this patch, much appreciated!

[snip]

Hmm, someone posted a list of people using autoconf somewhat recently to the mailing-list ... I don't have it to hand, but cygwin was one of the projects using it.

Yes, exactly.

Hmm, I am not convinced (yet) that meson is all that useful either. ;)
 

I am trying very hard not to express a view on this debate. :)

[well, except that I find CMake to be absolutely awful!]

Thanks!

ATB, Ramsay Jones

On 5/8/25 7:01 PM, Ramsay Jones wrote:

Thanks for the correction. This solves my major concern...

... because to my way of thinking, the ultimate proof of usefulness is that people, well, *use* it. Gentoo uses Meson, ipso facto it is useful. :)

From my experience with the ./configure script it wasn't clear to *me* that anyone did use it (and I did a non-exhaustive check of other distributors). If cygwin uses it, it is useful and the question becomes *whether* to (properly) deprecate it after evaluating the existing options and balancing use cases with maintenance burden, rather than "just let it rot until we finish discussing its likely deletion".

I'm still not volunteering to do the actual fixing of ./configure :D but testing is easy if someone else wrote the fix...

Ramsay Jones <ramsay@ramsayjones.plus.com> writes:

Certainly nice to see these settings taught to be more careful.

Thanks.

Ramsay Jones <ramsay@ramsayjones.plus.com> writes:

Just out of curiosity (because this cannot be a regression, since the original removed one used the same constructs).

I am guessing from the presence of double quote around the value that these strings are not directly used to invoke the compiler without involving any shell (in other words, you wouldn't want these quotes if you are shoving these strings in argv[] yourself to feed execv()).

How does the above, and get_option() in particular, cope with a pathname that has letters with special meanings to the shell when they appear inside double-quote pair (like backquote or backslash or even a dollar sign)? On the Makefile side we give VAR_SQ for a raw variable VAR and use the latter to write something like

        -DETC_GITATTRIBUTES='"$(ETC_GITATTRIBUTES_SQ)"'

to make sure we won't be broken by them. Is Meson giving us an equivalent to us for free by simply using get_option() here?

Thanks.

On 5/8/25 5:48 PM, Junio C Hamano wrote:

Meson uses strong implicit typing. The object type of '"' is a string with value of double-quote-char, and the type of libgit_c_args is "array". It's not a result of get_option() here, except inasmuch as get_option() returned a string type.

Meson guarantees that arrays of strings e.g.

libgit_c_args = [
    '-Dfoo=string containing the $ (mighty dollar)',
    '-Dbar=string containing the ` soft-deprecated',
    '-Doopsies=string containing the \' (you read that right)',
]

are passed to the shell in a manner suitable for reinterpretation as an argv array, notwithstanding other concerns (e.g. I believe there's some mingw hack regarding doubling backslash escapes so they don't get eaten). And of course this is conditional on the idea that it is possible to reliably pass arguments on the Windows command line, which doesn't have the notion of an array.

So, given that meson takes care of this, the actual value of the -D define will be

string containing the $ (mighty dollar)

etc.

e.g. here is the ninja output:

[1/3] ccache cc -Ifoo.p -I. -I.. -fdiagnostics-color=always -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -O0 -g '-Dfoo=string containing the $ (mighty dollar)' '-Dbar=string containing the ` soft-deprecated' '-Doopsies=string containing the '"'"' (you read that right)' -MD -MQ foo.p/foo.c.o -MF foo.p/foo.c.o.d -o foo.p/foo.c.o -c ../foo.c <command-line>: warning: missing terminating ' character

Notice that the array contained a single quote using a meson string type backslash escape, but the generated command line chose to shell-escape it as ' ... '"'"' .... '

In this case, the Makefile does:

-DETC_GITATTRIBUTES='"$(ETC_GITATTRIBUTES_SQ)"'

and if I understand correctly the _SQ is to handle single quotes in the directory name:

-DETC_GITATTRIBUTES='"/etc/git'\''s attribute file"'

Or in meson,

libgit_c_args += [
    '-DETC_GITATTRIBUTES="/etc/git\'s attribute file"',
]

compiles as:

[1/3] ccache cc -Ifoo.p -I. -I.. -fdiagnostics-color=always -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -O0 -g '-Dfoo=string containing the $ (mighty dollar)' '-Dbar=string containing the ` soft-deprecated' '-Doopsies=string containing the '"'"' (you read that right)' '-DETC_GITATTRIBUTES="/etc/git'"'"'s attribute file"' -MD -MQ foo.p/foo.c.o -MF foo.p/foo.c.o.d -o foo.p/foo.c.o -c ../foo.c

Meson has refrained from backslashes again:

ccache cc '-DETC_GITATTRIBUTES="/etc/git'"'"'s attribute file"'

Double quotes are part of the define value, single quote gets de-escaped via the sequence:

'"'"'

instead of the sequence

'\''

Eli Schwartz <eschwartz@gentoo.org> writes:

Very nice. Just I wanted to hear from a system that we are trying to adopt and promote ;-)

On 08/05/2025 22:48, Junio C Hamano wrote:

Err ... no, meson is somewhat broken here, for example see [0]. To be fair, it could simply be that I am too dumb to understand what meson is doing (and I haven't really studied the documentation or the code).

Hopefully, someone who knows meson will be able to answer your question.

[0] https://lore.kernel.org/git/a5795bfa-cc02-4c9a-b7d2-4924a94cd0db@ramsayjones.plus.com/

Thanks.

ATB, Ramsay Jones

On Thu, May 08, 2025 at 05:44:37PM +0100, Ramsay Jones wrote:

Instead of `get_option('sysconfdir') + '/gitconfig'` you can say `get_option('sysconfdir') / 'gitconfig'`. It's a bit pointless in this case and not really needed, but '/' has some special magic for handling absolute and relative paths.

Nit: let's maybe add an empty newline after each of these blocks to make
it a bit easier to see where handling for each specific option stops.

Makes sense. Should we maybe document the default values here now that they aren't immediately obvious anymore?

Patrick

On 09/05/2025 09:51, Patrick Steinhardt wrote:

OK, TIL. I just looked this up ([0]) and I am not sure such 'magic' is always a good thing. ;)

[0] https://mesonbuild.com/Syntax.html#string-path-building

OK, will do.

good idea.

Thanks!

ATB, Ramsay Jones

Hmm, I seem to have misunderstood the '--chain-reply-to' documentation on the 'git send-email' man page! :( Sorry about that.

[I had intended a shallow threading].

On 08/05/2025 17:44, Ramsay Jones wrote:

Note that I cannot test the new autoconf check in patch #5 (I don't have access to a Solaris system). I _think_ it will correctly unset HAVE_SYSINFO on Solaris, but I cannot confirm that. (I can only test on Linux and cygwin).

Note that it is patch #2 "meson: correct install location of YAML.pm" that conflicts with the 'seen' branch.

Changes in v2:

Patch #3 is the only one changed (as a result of Patrick's review [0]):

 - add some blank lines to make the option handling blocks
   easier to see.
 - add a comment to 'gitconfig' and 'gitattributes' options
   to indicate the default values.

Note: The indicated defaults for the 'gitconfig' and 'gitattributes'
are only valid when the 'prefix' option is defaulted (or not /usr).
Indicating the 'correct' value when -Dprefix=/usr in the comment
would consume too much space. Is this acceptable, or is it too
confusing/misleading?

Also, thanks to Eli for testing patch #5 on Solaris and confirming that it fixes the regression [1].

Note that I did a test merge to master@38af977b81 without issue and to next@889b7c5bd8 and seen@d8088176ab. The conflict which showed up in v1 against the 'seen' branch now appears in 'next' and has the same resolution as v1.

A range-diff against v1 is given below.

[0] https://lore.kernel.org/git/aB3CDOljn9zJsVwt@pks.im/ [1] https://lore.kernel.org/git/9baad29d-a5bf-443d-98a1-36d7020e5835@gentoo.org/

v1 cover letter follows:

This series (part 2) continues the miscellaneous changes to the make, meson and autoconf build systems. I am sending this part a little earlier than I expected, so there will now be a part 3!

The reason for the early posting is to try and avoid an regression in the autoconf build system (see patch #5). Hopefully, we still have time in this cycle to get patch #5 included.

This series is based on commit 6f84262c44 ("The eleventh batch", 2025-05-05)

I did a test merge to 'next'@629a3ecd64 without issue, but 'seen'@71cfd25022 had a small conflict with commit 1a2929c851 ("meson: allow customize perl installation path", 2025-04-24) on the 'dd/meson-perl-custom-path' branch. (I note that a new version of that patch was posted to the list today).

The fixup looks like:

    diff --cc perl/Git/SVN/Memoize/meson.build
    index 4c589b30c3,8c2e80d2d2..d6209dc3bf
    --- a/perl/Git/SVN/Memoize/meson.build
    +++ b/perl/Git/SVN/Memoize/meson.build
    @@@ -3,6 -3,6 +3,6 @@@ test_dependencies += custom_target
        output: 'YAML.pm',
        command: generate_perl_command,
        install: true,
    -   install_dir: perllibdir / 'Git/SVN',
     -  install_dir: get_option('datadir') / 'perl5/Git/SVN/Memoize',
    ++  install_dir: perllibdir / 'Git/SVN/Memoize',
        depends: [git_version_file],
      )

ATB, Ramsay Jones

Ramsay Jones (5):
  meson.build: quote the GITWEBDIR build configuration
  meson: correct install location of YAML.pm
  meson: correct path to system config/attribute files
  meson.build: correct setting of GIT_EXEC_PATH
  configure.ac: upgrade to a compilation check for sysinfo

 configure.ac                     | 25 ++++++++++++++++++++++---
 meson.build                      | 30 +++++++++++++++++++++++++-----
 meson_options.txt                |  4 ++--
 perl/Git/SVN/Memoize/meson.build |  2 +-
 4 files changed, 50 insertions(+), 11 deletions(-)

range-diff against v1:

1:  d5847ef791 = 1:  1f3d34eafd meson.build: quote the GITWEBDIR build configuration
2:  49e2ec6fd2 = 2:  1b7751914a meson: correct install location of YAML.pm
3:  fece809f11 ! 3:  a385bbed83 meson: correct path to system config/attribute files
    @@ meson.build: libgit_c_args = [
     +else
     +  libgit_c_args += '-DETC_GITATTRIBUTES="' + get_option('sysconfdir') + '/gitattributes"'
     +endif
    ++
     +system_config = get_option('gitconfig')
     +if system_config != ''
     +  libgit_c_args += '-DETC_GITCONFIG="' + system_config + '"'
     +else
     +  libgit_c_args += '-DETC_GITCONFIG="' + get_option('sysconfdir') + '/gitconfig"'
     +endif
    ++
      editor_opt = get_option('default_editor')
      if editor_opt != '' and editor_opt != 'vi'
        libgit_c_args += '-DDEFAULT_EDITOR="' + editor_opt + '"'
    @@ meson_options.txt: option('default_pager', type: 'string', value: 'less',
      option('default_editor', type: 'string', value: 'vi',
        description: 'Fall-back editor.')
     -option('gitconfig', type: 'string', value: '/etc/gitconfig',
    -+option('gitconfig', type: 'string',
    ++option('gitconfig', type: 'string', # default 'etc/gitconfig'
        description: 'Path to the global git configuration file.')
     -option('gitattributes', type: 'string', value: '/etc/gitattributes',
    -+option('gitattributes', type: 'string',
    ++option('gitattributes', type: 'string', # default 'etc/gitattributes'
        description: 'Path to the global git attributes file.')
      option('pager_environment', type: 'string', value: 'LESS=FRX LV=-c',
        description: 'Environment used when spawning the pager')
4:  d49afaedf3 = 4:  0d00951475 meson.build: correct setting of GIT_EXEC_PATH
5:  69848e557f = 5:  150e4110d2 configure.ac: upgrade to a compilation check for sysinfo

The build configuration options with (non-empty) values, for example filesystem paths potentially containing spaces, have been set using the '.set_quoted()' method. However, the GITWEBDIR value has been set using the '.set()' method instead. In order to correctly quote the GITWEBDIR value, replace the '.set()' method with '.set_quoted()'.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

When executing an 'meson install' the YAML.pm file is incorrectly placed in the <prefix>/share/perl5/Git/SVN directory. The YAML.pm file should be placed in a 'Memoize' subdirectory instead. In order to correct the location, update the 'install_dir' of the relevant target in the 'perl/Git/SVN/Memoize/meson.build' file.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 perl/Git/SVN/Memoize/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

The path to the system-wide config and attributes files are not being set correctly in the meson build. Unless explicitly overridden on the command line during setup, the 'gitconfig' and 'gitattributes' options are defaulting to absolute paths in the '/etc' system directory. This is only appropriate if the <prefix> is set specifically to '/usr'.

The directory in which these files are placed is generally referred to as the 'system configuration directory' or 'sysconfdir' for short. When the prefix is '/usr' then the sysconfdir is usually set to '/etc', but any other value for prefix results in the relative directory value 'etc' instead. (eg if prefix is '/usr/local', then the 'etc' relative value results in a system configuration directory of '/usr/local/etc'). When setting the 'sysconfdir' builtin option value, the meson system uses exactly this algorithm, so we can use get_option('sysconfdir') directly when setting the (non-overridden) build variables.

In order to allow for overriding from the command line, remove the default values specified for the 'gitconfig' and 'gitattributes' options in the 'meson_options.txt' file. This allows the user to specify any pathname for those options, while being able to test for the unset (empty) value. An absolute pathname will be used unchanged and a relative pathname will be appended to '<prefix>/'. These values are then used to set the 'ETC_GITCONFIG' and 'ETC_GITATTRIBUTES' build variables which are, in turn, passed to the compiler as '-D' arguments.

When the 'gitconfig' or 'gitattributes' options are not used, then use the built-in 'sysconfdir' and set the ETC_GITCONFIG build variable to the string "<sysconfdir>/gitconfig". Similarly, set ETC_ATTRIBUTES to "<sysconfdir>/gitattributes".

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build       | 16 ++++++++++++++--
 meson_options.txt |  4 ++--
 2 files changed, 16 insertions(+), 4 deletions(-)

On Tue, May 13, 2025 at 08:17:24PM +0100, Ramsay Jones wrote:

Nit: I still think that we should use `get_option('sysconfdir') /
'gitattributes'`, with the slash instead of a plus, mostly because it is
more idiomatic and reads better. But that alone doesn't warrant a
reroll.

I'd prefer if we documented the default value in the description. Otherwise it is impossible to discover it without having a look at the sources.

Other than that the range-diff looks as expected, thanks!

Patrick

On 14/05/2025 05:36, Patrick Steinhardt wrote:

OK, if I need to re-roll, I will fix this up. (but see below)

Hmm, but how do you get the description! :)

I applied the following patch on top:

  diff --git a/meson.build b/meson.build
  index 28276e5305..bd14bc15a1 100644
  --- a/meson.build
  +++ b/meson.build
  @@ -771,14 +771,14 @@ system_attributes = get_option('gitattributes')
   if system_attributes != ''
     libgit_c_args += '-DETC_GITATTRIBUTES="' + system_attributes + '"'
   else
  -  libgit_c_args += '-DETC_GITATTRIBUTES="' + get_option('sysconfdir') + '/gitattributes"'
  +  libgit_c_args += '-DETC_GITATTRIBUTES="' + get_option('sysconfdir') / 'gitattributes"'
   endif
   
   system_config = get_option('gitconfig')
   if system_config != ''
     libgit_c_args += '-DETC_GITCONFIG="' + system_config + '"'
   else
  -  libgit_c_args += '-DETC_GITCONFIG="' + get_option('sysconfdir') + '/gitconfig"'
  +  libgit_c_args += '-DETC_GITCONFIG="' + get_option('sysconfdir') / 'gitconfig"'
   endif
   
   editor_opt = get_option('default_editor')
  diff --git a/meson_options.txt b/meson_options.txt
  index ff877e67ce..7a4b896f7e 100644
  --- a/meson_options.txt
  +++ b/meson_options.txt
  @@ -4,9 +4,9 @@ option('default_pager', type: 'string', value: 'less',
   option('default_editor', type: 'string', value: 'vi',
     description: 'Fall-back editor.')
   option('gitconfig', type: 'string', # default 'etc/gitconfig'
  -  description: 'Path to the global git configuration file.')
  +  description: 'Path to the global git configuration file. (default: etc/gitconfig)')
   option('gitattributes', type: 'string', # default 'etc/gitattributes'
  -  description: 'Path to the global git attributes file.')
  +  description: 'Path to the global git attributes file. (default: etc/gitattributes)')
   option('pager_environment', type: 'string', value: 'LESS=FRX LV=-c',
     description: 'Environment used when spawning the pager')
   option('perl_cpan_fallback', type: 'boolean', value: true,
----

So, the addition of the '(default: <value>)' to the description field is intended to mimic the setup help text for the built-in meson options:

  $ meson help setup
  usage: meson setup [-h] [--prefix PREFIX] [--bindir BINDIR] [--datadir DATADIR]
  
  ...
  
  options:
    -h, --help                            show this help message and exit
    --prefix PREFIX                       Installation prefix (default:
                                          /usr/local).
    --bindir BINDIR                       Executable directory (default: bin).
    --datadir DATADIR                     Data file directory (default: share).
    --includedir INCLUDEDIR               Header file directory (default:
                                          include).
    --infodir INFODIR                     Info page directory (default:
                                          share/info).
    --libdir LIBDIR                       Library directory (default:
                                          lib/x86_64-linux-gnu).
    --licensedir LICENSEDIR               Licenses directory (default: ).
    --libexecdir LIBEXECDIR               Library executable directory (default:
                                          libexec).
    --localedir LOCALEDIR                 Locale data directory (default:
                                          share/locale).
    --localstatedir LOCALSTATEDIR         Localstate data directory (default:
                                          var).
    --mandir MANDIR                       Manual page directory (default:
                                          share/man).
    --sbindir SBINDIR                     System executable directory (default:
                                          sbin).
    --sharedstatedir SHAREDSTATEDIR       Architecture-independent data directory
                                          (default: com).
    --sysconfdir SYSCONFDIR               Sysconf data directory (default: etc).
  
  ...
  
  $ 

Indeed, there appears to be no way to display the project specific options to the user *before* configuring a build directory.

  $ pwd
  /home/ramsay/git
  $ meson introspect --buildoptions
  Current directory is not a meson build directory.
  Please specify a valid build dir or change the working directory to it.
  $ 

Note that I don't recommend 'meson introspect --buildoptions' as a means for the user to inspect the available options, but it does allow me to check that the description field looks correct:

  $ meson introspect --buildoptions build | jq | grep gitconfig
      "name": "gitconfig",
      "description": "Path to the global git configuration file. (default: etc/gitconfig)"
  $ meson introspect --buildoptions build | jq | grep gitattributes
      "name": "gitattributes",
      "description": "Path to the global git attributes file. (default: etc/gitattributes)"
  $ 

The only way I have found to display the project options to the user (after
configuring the project) is using 'meson configure', thus:  
  
  $ meson configure build
  
  ...
  
    Project options    Current Value        Possible Values      Description      
    -----------------  -------------        ---------------      -----------      
  benchmark_large_repo                                           Large repository 
                                                                 to copy for the  
                                                                 performance      
                                                                 tests. Should be 
                                                                 at least the size
                                                                 of the Linux     
                                                                 repository.      

  ...

    gitattributes                                                Path to the      
                                                                 global git       
                                                                 attributes file. 
                                                                 (default: etc/git
                                                                 attributes)      
    gitconfig                                                    Path to the      
                                                                 global git       
                                                                 configuration    
                                                                 file. (default:  
                                                                 etc/gitconfig)   
  
  ...
  
  $ 

[Yes, I use 80 column terminals! :) ]

Note that this display shows the *current* value, not the default value, and (once again) in this case there really isn't a default value! ;) (iff prefix is exactly '/usr', then the 'default' is eg. '/etc/gitconfig').

Of course, the current value would be the default value unless you have set the value on the command-line (of which you would presumably be aware).

[Well, it can be argued that eg. 'etc/gitconfig' is the default value for the project option 'gitconfig', but that is just one input to determine the actual path compiled into git (which _may_depend on the value of another option ie. 'prefix')].

Having said that, the --sysconfdir default is shown as 'etc' (see above) and that has (*is*) the same problem (ie it is '/etc' iff prefix is '/usr').

Also, looking through that list, other options which are similarly specified to gitconfig/gitattributes don't have their 'default' noted in the description. Why make an exception for these options?

Is this what you wanted to see? If so, then I can submit a v3 with the above changes. Just let me know.

Thanks.

ATB, Ramsay Jones

On 5/15/25 12:42 PM, Ramsay Jones wrote:

Well, so-so.

eschwartz@acleverhostname ~/git/git $ meson configure .

meson.build:208:0: ERROR: None of values [] are supported by the C compiler. Possible values for option "C_std" are ['none', 'c89', 'c99', 'c11', 'c17', 'c18', 'c2x', 'c23', 'gnu89', 'gnu99', 'gnu11', 'gnu17', 'gnu18', 'gnu2x', 'gnu23']

But also,

$ sed -i '/c_std=/d' meson.build && PAGER=cat COLUMNS=80 meson configure .

WARNING: The source directory instead of the build directory was specified.
WARNING: Only the default values for the project are printed.

Core properties:
  Source dir /home/eschwartz/git/git

Main project options:

  Core options       Default Value        Possible Values
Description
  --------------     -------------        ---------------
-----------
  auto_features      auto                 [enabled, disabled,  Override
value of
                                           auto]               all
'auto'
                                                               features

[...]

I'm not completely certain why this evaluates as an empty node:

```(meson.version().version_compare('>=1.3.0') ? 'gnu99,c11' : 'gnu99') ```

but it (meson configure) is part of the AST interpreter, not the runtime one, which I know less about...

On 15/05/2025 18:51, Eli Schwartz wrote:

[snip]

Ah, interesting. When it came time to test this patch, I spent about half an hour trying to get 'meson configure' to tell me about the project options, because I had a distant memory of having done it before at one point ... :)

Hmm, maybe it was before commit 13cb20fc46 ("meson: fix compilation with Visual Studio", 2025-01-22). If I (effectively) revert that commit, then 'meson configure' works fine for me (you don't even need the '.').

TIL. Thanks!

ATB, Ramsay Jones

On Thu, May 15, 2025 at 05:42:00PM +0100, Ramsay Jones wrote:

[snip]

Yup, that's how I typically do it.

[snip]

It's not so much about one being exceptional, it's rather that I didn't think about it for the other options. Ideally, we'd document the default for all values where we don't have a hardcoded one.

Yup, the diff you had looks exactly like what I expected. Thanks!

Patrick

For the non-'runtime prefix' case, the meson build sets the GIT_EXEC_PATH build variable to an absolute path equivalent to <prefix>/libexec/git-core. In comparison, the default make build sets it to a relative path equivalent to 'libexec/git-core'. Indeed, the make build requires the use of some means outside of the Makefile (eg. config.mak[.*] or the command-line) to set GIT_EXEC_PATH to anything other than 'libexec/git-core'.

For example, the make invocation:

  $ make gitexecdir=/some/other/bin all install

will build git with GIT_EXEC_PATH set to '/some/other/bin' and install the 'library' executables to that location. However, without setting the 'gitexecdir' make variable, irrespective of the 'runtime prefix' setting, the GIT_EXEC_PATH is always set to 'libexec/git-core'.

The meson built-in 'libexecdir' option can be used to provide a similar configurability. The default value for the option is 'libexec'. Attempting to set the option to '' on the command-line, will reset it to the '.' string, presumably to ensure a relative path value.

This commit allows the meson build, similar to the above, to configure the project like:

  $ meson setup --buildtype=debugoptimized -Dprefix=$HOME -Dpcre2=disabled \
      -Dlibexecdir=/some/other/bin build

so that the GIT_EXEC_PATH is set to '/some/other/bin'. Absent the -Dlibexecdir argument, the GIT_EXEC_PATH is set to 'libexec/git-core'.

In order to correct the value of GIT_EXEC_PATH, default the value to the static string value 'libexec/git-core', and only override if the value of the 'libexecdir' option has a value different to 'libexec' or '.'. Also, like the Makefile, add a check for an absolute path when the runtime prefix option is true (and if so, error out).

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

This completely breaks meson builds with 'libexecdir' set. Git can not find any helper tools because 'git_exec_path' is set incorrectly.

It supposed to be:

--- meson.build +++ meson.build

Commit f5e3c6c57d ("meson: do a full usage-based compile check for sysinfo", 2025-04-25) updated the 'sysinfo()' check, as part of the meson build, due to the failure of the check on Solaris. Prior to that commit, the meson build only checked the availability of the '<sys/sysinfo.h>' header file. On Solaris, both the header and the 'sysinfo()' function exist, but are completely unrelated to the same function on Linux (and cygwin).

Commit 50dec7c566 ("config.mak.uname: add sysinfo() configuration for cygwin", 2025-04-17) added a similar 'sysinfo()' check to the autoconf build. This check looked for the 'sysinfo()' function itself, rather that just the header, but it will fail (incorrectly set HAVE_SYSINFO) for the same reason.

In order to correctly identify the 'sysinfo()' function we require as part of 'git-gc' (used in the 'total_ram() function), we also upgrade to a compilation check, in a similar way to the meson commit. Note that since commit c9a51775a3 ("builtin/gc.c: correct RAM calculation when using sysinfo", 2025-04-17) both the 'totalram' and 'mem_unit' fields of the 'struct sysinfo' are used, so the new check includes both of those fields in the compile check.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 configure.ac | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

Ramsay Jones <ramsay@ramsayjones.plus.com> writes:

Yeah, thanks, all.

Hmph, For #5 I am seeing this difference:

    @@ Commit message
         Commit 50dec7c566 ("config.mak.uname: add sysinfo() configuration for
         cygwin", 2025-04-17) added a similar 'sysinfo()' check to the autoconf
         build. This check looked for the 'sysinfo()' function itself, rather
    -    than just the header, but it will fail (incorrectly set HAVE_SYSINFO)
    +    that just the header, but it will fail (incorrectly set HAVE_SYSINFO)
         for the same reason.
     
         In order to correctly identify the 'sysinfo()' function we require as

The original comes from what was posted in the first iteration, and somehow the change is not showing in your range-diff, which is a bit disturbing.

I think for now I'll just amend the log message of #5 back to what was in the previous round locally.

Thanks.

On 13/05/2025 21:13, Junio C Hamano wrote:

Oops! yeah, I noticed the typo late in the last round and changed that patch text directly. :)

I could have sworn that I made the same change to the commit message as well, but ...

Sorry about that!

Yes please! Thanks.

ATB, Ramsay Jones

Changes in v3:

Patch #3 changed as a result of Patrick's review [*]:

 - use the '/' magic string operator when setting the
   ETC_GIT{CONFIG,ATTRIBUTES} build options.
 - add the default values to the 'description' fields
   for the 'gitconfig' and 'gitattributes' option
   definitions

Also, Junio, the range-diff below shows the typo fixup, but you should find that it doesn't show for you this time. ;)

[yes, I did fix it up locally, but then overwrote it from my cygwin repo ... Ahem! ;) ]

Again, I did a test merge to master@1a8a4971cc without issue and to next@0be31eac6b and seen@d36a872499. The conflict which showed up in v1 against the 'seen' branch now appears in 'next' and has the same resolution as v1.

A range-diff against v2 is given below.

[*] https://lore.kernel.org/git/aCbQ9OX2vqF82au8@pks.im/

Changes in v2:

Patch #3 is the only one changed (as a result of Patrick's review [0]):

 - add some blank lines to make the option handling blocks
   easier to see.
 - add a comment to 'gitconfig' and 'gitattributes' options
   to indicate the default values.

Note: The indicated defaults for the 'gitconfig' and 'gitattributes'
are only valid when the 'prefix' option is defaulted (or not /usr).
Indicating the 'correct' value when -Dprefix=/usr in the comment
would consume too much space. Is this acceptable, or is it too
confusing/misleading?

Also, thanks to Eli for testing patch #5 on Solaris and confirming that it fixes the regression [1].

Note that I did a test merge to master@38af977b81 without issue and to next@889b7c5bd8 and seen@d8088176ab. The conflict which showed up in v1 against the 'seen' branch now appears in 'next' and has the same resolution as v1.

A range-diff against v1 is given below.

[0] https://lore.kernel.org/git/aB3CDOljn9zJsVwt@pks.im/ [1] https://lore.kernel.org/git/9baad29d-a5bf-443d-98a1-36d7020e5835@gentoo.org/

v1 cover letter follows:

This series (part 2) continues the miscellaneous changes to the make, meson and autoconf build systems. I am sending this part a little earlier than I expected, so there will now be a part 3!

The reason for the early posting is to try and avoid an regression in the autoconf build system (see patch #5). Hopefully, we still have time in this cycle to get patch #5 included.

This series is based on commit 6f84262c44 ("The eleventh batch", 2025-05-05)

I did a test merge to 'next'@629a3ecd64 without issue, but 'seen'@71cfd25022 had a small conflict with commit 1a2929c851 ("meson: allow customize perl installation path", 2025-04-24) on the 'dd/meson-perl-custom-path' branch. (I note that a new version of that patch was posted to the list today).

The fixup looks like:

    diff --cc perl/Git/SVN/Memoize/meson.build
    index 4c589b30c3,8c2e80d2d2..d6209dc3bf
    --- a/perl/Git/SVN/Memoize/meson.build
    +++ b/perl/Git/SVN/Memoize/meson.build
    @@@ -3,6 -3,6 +3,6 @@@ test_dependencies += custom_target
        output: 'YAML.pm',
        command: generate_perl_command,
        install: true,
    -   install_dir: perllibdir / 'Git/SVN',
     -  install_dir: get_option('datadir') / 'perl5/Git/SVN/Memoize',
    ++  install_dir: perllibdir / 'Git/SVN/Memoize',
        depends: [git_version_file],
      )

ATB, Ramsay Jones

Ramsay Jones (5):
  meson.build: quote the GITWEBDIR build configuration
  meson: correct install location of YAML.pm
  meson: correct path to system config/attribute files
  meson.build: correct setting of GIT_EXEC_PATH
  configure.ac: upgrade to a compilation check for sysinfo

 configure.ac                     | 25 ++++++++++++++++++++++---
 meson.build                      | 30 +++++++++++++++++++++++++-----
 meson_options.txt                |  8 ++++----
 perl/Git/SVN/Memoize/meson.build |  2 +-
 4 files changed, 52 insertions(+), 13 deletions(-)

range-diff against v2:

1:  1f3d34eafd = 1:  ac97fdc76e meson.build: quote the GITWEBDIR build configuration
2:  1b7751914a = 2:  181738d371 meson: correct install location of YAML.pm
3:  a385bbed83 ! 3:  1f4c74973c meson: correct path to system config/attribute files
    @@ meson.build: libgit_c_args = [
     +if system_attributes != ''
     +  libgit_c_args += '-DETC_GITATTRIBUTES="' + system_attributes + '"'
     +else
    -+  libgit_c_args += '-DETC_GITATTRIBUTES="' + get_option('sysconfdir') + '/gitattributes"'
    ++  libgit_c_args += '-DETC_GITATTRIBUTES="' + get_option('sysconfdir') / 'gitattributes"'
     +endif
     +
     +system_config = get_option('gitconfig')
     +if system_config != ''
     +  libgit_c_args += '-DETC_GITCONFIG="' + system_config + '"'
     +else
    -+  libgit_c_args += '-DETC_GITCONFIG="' + get_option('sysconfdir') + '/gitconfig"'
    ++  libgit_c_args += '-DETC_GITCONFIG="' + get_option('sysconfdir') / 'gitconfig"'
     +endif
     +
      editor_opt = get_option('default_editor')
    @@ meson_options.txt: option('default_pager', type: 'string', value: 'less',
      option('default_editor', type: 'string', value: 'vi',
        description: 'Fall-back editor.')
     -option('gitconfig', type: 'string', value: '/etc/gitconfig',
    -+option('gitconfig', type: 'string', # default 'etc/gitconfig'
    -   description: 'Path to the global git configuration file.')
    +-  description: 'Path to the global git configuration file.')
     -option('gitattributes', type: 'string', value: '/etc/gitattributes',
    +-  description: 'Path to the global git attributes file.')
    ++option('gitconfig', type: 'string', # default 'etc/gitconfig'
    ++  description: 'Path to the global git configuration file. (default: etc/gitconfig)')
     +option('gitattributes', type: 'string', # default 'etc/gitattributes'
    -   description: 'Path to the global git attributes file.')
    ++  description: 'Path to the global git attributes file. (default: etc/gitattributes)')
      option('pager_environment', type: 'string', value: 'LESS=FRX LV=-c',
        description: 'Environment used when spawning the pager')
    + option('perl_cpan_fallback', type: 'boolean', value: true,
4:  0d00951475 = 4:  97ff1613f5 meson.build: correct setting of GIT_EXEC_PATH
5:  150e4110d2 ! 5:  983488fe4e configure.ac: upgrade to a compilation check for sysinfo
    @@ Commit message
         Commit 50dec7c566 ("config.mak.uname: add sysinfo() configuration for
         cygwin", 2025-04-17) added a similar 'sysinfo()' check to the autoconf
         build. This check looked for the 'sysinfo()' function itself, rather
    -    that just the header, but it will fail (incorrectly set HAVE_SYSINFO)
    +    than just the header, but it will fail (incorrectly set HAVE_SYSINFO)
         for the same reason.
     
         In order to correctly identify the 'sysinfo()' function we require as

The build configuration options with (non-empty) values, for example filesystem paths potentially containing spaces, have been set using the '.set_quoted()' method. However, the GITWEBDIR value has been set using the '.set()' method instead. In order to correctly quote the GITWEBDIR value, replace the '.set()' method with '.set_quoted()'.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

When executing an 'meson install' the YAML.pm file is incorrectly placed in the <prefix>/share/perl5/Git/SVN directory. The YAML.pm file should be placed in a 'Memoize' subdirectory instead. In order to correct the location, update the 'install_dir' of the relevant target in the 'perl/Git/SVN/Memoize/meson.build' file.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 perl/Git/SVN/Memoize/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

The path to the system-wide config and attributes files are not being set correctly in the meson build. Unless explicitly overridden on the command line during setup, the 'gitconfig' and 'gitattributes' options are defaulting to absolute paths in the '/etc' system directory. This is only appropriate if the <prefix> is set specifically to '/usr'.

The directory in which these files are placed is generally referred to as the 'system configuration directory' or 'sysconfdir' for short. When the prefix is '/usr' then the sysconfdir is usually set to '/etc', but any other value for prefix results in the relative directory value 'etc' instead. (eg if prefix is '/usr/local', then the 'etc' relative value results in a system configuration directory of '/usr/local/etc'). When setting the 'sysconfdir' builtin option value, the meson system uses exactly this algorithm, so we can use get_option('sysconfdir') directly when setting the (non-overridden) build variables.

In order to allow for overriding from the command line, remove the default values specified for the 'gitconfig' and 'gitattributes' options in the 'meson_options.txt' file. This allows the user to specify any pathname for those options, while being able to test for the unset (empty) value. An absolute pathname will be used unchanged and a relative pathname will be appended to '<prefix>/'. These values are then used to set the 'ETC_GITCONFIG' and 'ETC_GITATTRIBUTES' build variables which are, in turn, passed to the compiler as '-D' arguments.

When the 'gitconfig' or 'gitattributes' options are not used, then use the built-in 'sysconfdir' and set the ETC_GITCONFIG build variable to the string "<sysconfdir>/gitconfig". Similarly, set ETC_ATTRIBUTES to "<sysconfdir>/gitattributes".

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build       | 16 ++++++++++++++--
 meson_options.txt |  8 ++++----
 2 files changed, 18 insertions(+), 6 deletions(-)

On Fri, May 16, 2025 at 07:48:41PM +0100, Ramsay Jones wrote:

Sorry to be nitpicky, but the default information is duplicated. We now have it once as comment and once as description. Other than that this version looks great to me, thanks!

Patrick

For the non-'runtime prefix' case, the meson build sets the GIT_EXEC_PATH build variable to an absolute path equivalent to <prefix>/libexec/git-core. In comparison, the default make build sets it to a relative path equivalent to 'libexec/git-core'. Indeed, the make build requires the use of some means outside of the Makefile (eg. config.mak[.*] or the command-line) to set GIT_EXEC_PATH to anything other than 'libexec/git-core'.

For example, the make invocation:

  $ make gitexecdir=/some/other/bin all install

will build git with GIT_EXEC_PATH set to '/some/other/bin' and install the 'library' executables to that location. However, without setting the 'gitexecdir' make variable, irrespective of the 'runtime prefix' setting, the GIT_EXEC_PATH is always set to 'libexec/git-core'.

The meson built-in 'libexecdir' option can be used to provide a similar configurability. The default value for the option is 'libexec'. Attempting to set the option to '' on the command-line, will reset it to the '.' string, presumably to ensure a relative path value.

This commit allows the meson build, similar to the above, to configure the project like:

  $ meson setup --buildtype=debugoptimized -Dprefix=$HOME -Dpcre2=disabled \
      -Dlibexecdir=/some/other/bin build

so that the GIT_EXEC_PATH is set to '/some/other/bin'. Absent the -Dlibexecdir argument, the GIT_EXEC_PATH is set to 'libexec/git-core'.

In order to correct the value of GIT_EXEC_PATH, default the value to the static string value 'libexec/git-core', and only override if the value of the 'libexecdir' option has a value different to 'libexec' or '.'. Also, like the Makefile, add a check for an absolute path when the runtime prefix option is true (and if so, error out).

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

Commit f5e3c6c57d ("meson: do a full usage-based compile check for sysinfo", 2025-04-25) updated the 'sysinfo()' check, as part of the meson build, due to the failure of the check on Solaris. Prior to that commit, the meson build only checked the availability of the '<sys/sysinfo.h>' header file. On Solaris, both the header and the 'sysinfo()' function exist, but are completely unrelated to the same function on Linux (and cygwin).

Commit 50dec7c566 ("config.mak.uname: add sysinfo() configuration for cygwin", 2025-04-17) added a similar 'sysinfo()' check to the autoconf build. This check looked for the 'sysinfo()' function itself, rather than just the header, but it will fail (incorrectly set HAVE_SYSINFO) for the same reason.

In order to correctly identify the 'sysinfo()' function we require as part of 'git-gc' (used in the 'total_ram() function), we also upgrade to a compilation check, in a similar way to the meson commit. Note that since commit c9a51775a3 ("builtin/gc.c: correct RAM calculation when using sysinfo", 2025-04-17) both the 'totalram' and 'mem_unit' fields of the 'struct sysinfo' are used, so the new check includes both of those fields in the compile check.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 configure.ac | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

Changes in v4:

Patch #3 changed as a result of Patricks review [+]:

 - remove comment showing the default option values for
   'gitattributes' and 'gitconfig', since this now appears
   in the description field (ie remove duplicate info).

Again, I did a test merge to master@cb96e1697a, next@a128411c76 and seen@df1b4f9cf9. The conflict which showed up in v1 against the 'seen' branch now appears in the 'master' branch and has the same resolution as v1.

Note: the test-suite passes for both 'make test' and 'meson test'
on Linux and 'meson test' on cygwin. (I have already had to wait
3.5 hours for 'meson test' to run on cygwin, so I will run the
'make test' later [it takes 6+ hours] and let you know if it fails.
Given that the only change from last time is the removal of a comment
in the 'meson_options.txt' file, the chances of 'make test' failing
seem to be rather remote - famous last words! ;) ).

A range-diff against v3 is given below.

[+] https://lore.kernel.org/git/aCrekcz6onTFgEWw@pks.im/

Changes in v3:

Patch #3 changed as a result of Patrick's review [*]:

 - use the '/' magic string operator when setting the
   ETC_GIT{CONFIG,ATTRIBUTES} build options.
 - add the default values to the 'description' fields
   for the 'gitconfig' and 'gitattributes' option
   definitions

Also, Junio, the range-diff below shows the typo fixup, but you should find that it doesn't show for you this time. ;)

[yes, I did fix it up locally, but then overwrote it from my cygwin repo ... Ahem! ;) ]

Again, I did a test merge to master@1a8a4971cc without issue and to next@0be31eac6b and seen@d36a872499. The conflict which showed up in v1 against the 'seen' branch now appears in 'next' and has the same resolution as v1.

A range-diff against v2 is given below.

[*] https://lore.kernel.org/git/aCbQ9OX2vqF82au8@pks.im/

Changes in v2:

Patch #3 is the only one changed (as a result of Patrick's review [0]):

 - add some blank lines to make the option handling blocks
   easier to see.
 - add a comment to 'gitconfig' and 'gitattributes' options
   to indicate the default values.

Note: The indicated defaults for the 'gitconfig' and 'gitattributes'
are only valid when the 'prefix' option is defaulted (or not /usr).
Indicating the 'correct' value when -Dprefix=/usr in the comment
would consume too much space. Is this acceptable, or is it too
confusing/misleading?

Also, thanks to Eli for testing patch #5 on Solaris and confirming that it fixes the regression [1].

Note that I did a test merge to master@38af977b81 without issue and to next@889b7c5bd8 and seen@d8088176ab. The conflict which showed up in v1 against the 'seen' branch now appears in 'next' and has the same resolution as v1.

A range-diff against v1 is given below.

[0] https://lore.kernel.org/git/aB3CDOljn9zJsVwt@pks.im/ [1] https://lore.kernel.org/git/9baad29d-a5bf-443d-98a1-36d7020e5835@gentoo.org/

v1 cover letter follows:

This series (part 2) continues the miscellaneous changes to the make, meson and autoconf build systems. I am sending this part a little earlier than I expected, so there will now be a part 3!

The reason for the early posting is to try and avoid an regression in the autoconf build system (see patch #5). Hopefully, we still have time in this cycle to get patch #5 included.

This series is based on commit 6f84262c44 ("The eleventh batch", 2025-05-05)

I did a test merge to 'next'@629a3ecd64 without issue, but 'seen'@71cfd25022 had a small conflict with commit 1a2929c851 ("meson: allow customize perl installation path", 2025-04-24) on the 'dd/meson-perl-custom-path' branch. (I note that a new version of that patch was posted to the list today).

The fixup looks like:

    diff --cc perl/Git/SVN/Memoize/meson.build
    index 4c589b30c3,8c2e80d2d2..d6209dc3bf
    --- a/perl/Git/SVN/Memoize/meson.build
    +++ b/perl/Git/SVN/Memoize/meson.build
    @@@ -3,6 -3,6 +3,6 @@@ test_dependencies += custom_target
        output: 'YAML.pm',
        command: generate_perl_command,
        install: true,
    -   install_dir: perllibdir / 'Git/SVN',
     -  install_dir: get_option('datadir') / 'perl5/Git/SVN/Memoize',
    ++  install_dir: perllibdir / 'Git/SVN/Memoize',
        depends: [git_version_file],
      )

ATB, Ramsay Jones

Ramsay Jones (5):
  meson.build: quote the GITWEBDIR build configuration
  meson: correct install location of YAML.pm
  meson: correct path to system config/attribute files
  meson.build: correct setting of GIT_EXEC_PATH
  configure.ac: upgrade to a compilation check for sysinfo

 configure.ac                     | 25 ++++++++++++++++++++++---
 meson.build                      | 30 +++++++++++++++++++++++++-----
 meson_options.txt                |  8 ++++----
 perl/Git/SVN/Memoize/meson.build |  2 +-
 4 files changed, 52 insertions(+), 13 deletions(-)

range-diff against v3:

1:  ac97fdc76e = 1:  247bc82c01 meson.build: quote the GITWEBDIR build configuration
2:  181738d371 = 2:  a87f683a95 meson: correct install location of YAML.pm
3:  1f4c74973c ! 3:  40ea59efca meson: correct path to system config/attribute files
    @@ meson_options.txt: option('default_pager', type: 'string', value: 'less',
     -  description: 'Path to the global git configuration file.')
     -option('gitattributes', type: 'string', value: '/etc/gitattributes',
     -  description: 'Path to the global git attributes file.')
    -+option('gitconfig', type: 'string', # default 'etc/gitconfig'
    ++option('gitconfig', type: 'string',
     +  description: 'Path to the global git configuration file. (default: etc/gitconfig)')
    -+option('gitattributes', type: 'string', # default 'etc/gitattributes'
    ++option('gitattributes', type: 'string',
     +  description: 'Path to the global git attributes file. (default: etc/gitattributes)')
      option('pager_environment', type: 'string', value: 'LESS=FRX LV=-c',
        description: 'Environment used when spawning the pager')
4:  97ff1613f5 = 4:  a7d2f1e132 meson.build: correct setting of GIT_EXEC_PATH
5:  983488fe4e = 5:  a45b9dc650 configure.ac: upgrade to a compilation check for sysinfo

The build configuration options with (non-empty) values, for example filesystem paths potentially containing spaces, have been set using the '.set_quoted()' method. However, the GITWEBDIR value has been set using the '.set()' method instead. In order to correctly quote the GITWEBDIR value, replace the '.set()' method with '.set_quoted()'.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

When executing an 'meson install' the YAML.pm file is incorrectly placed in the <prefix>/share/perl5/Git/SVN directory. The YAML.pm file should be placed in a 'Memoize' subdirectory instead. In order to correct the location, update the 'install_dir' of the relevant target in the 'perl/Git/SVN/Memoize/meson.build' file.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 perl/Git/SVN/Memoize/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

The path to the system-wide config and attributes files are not being set correctly in the meson build. Unless explicitly overridden on the command line during setup, the 'gitconfig' and 'gitattributes' options are defaulting to absolute paths in the '/etc' system directory. This is only appropriate if the <prefix> is set specifically to '/usr'.

The directory in which these files are placed is generally referred to as the 'system configuration directory' or 'sysconfdir' for short. When the prefix is '/usr' then the sysconfdir is usually set to '/etc', but any other value for prefix results in the relative directory value 'etc' instead. (eg if prefix is '/usr/local', then the 'etc' relative value results in a system configuration directory of '/usr/local/etc'). When setting the 'sysconfdir' builtin option value, the meson system uses exactly this algorithm, so we can use get_option('sysconfdir') directly when setting the (non-overridden) build variables.

In order to allow for overriding from the command line, remove the default values specified for the 'gitconfig' and 'gitattributes' options in the 'meson_options.txt' file. This allows the user to specify any pathname for those options, while being able to test for the unset (empty) value. An absolute pathname will be used unchanged and a relative pathname will be appended to '<prefix>/'. These values are then used to set the 'ETC_GITCONFIG' and 'ETC_GITATTRIBUTES' build variables which are, in turn, passed to the compiler as '-D' arguments.

When the 'gitconfig' or 'gitattributes' options are not used, then use the built-in 'sysconfdir' and set the ETC_GITCONFIG build variable to the string "<sysconfdir>/gitconfig". Similarly, set ETC_ATTRIBUTES to "<sysconfdir>/gitattributes".

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build       | 16 ++++++++++++++--
 meson_options.txt |  8 ++++----
 2 files changed, 18 insertions(+), 6 deletions(-)

For the non-'runtime prefix' case, the meson build sets the GIT_EXEC_PATH build variable to an absolute path equivalent to <prefix>/libexec/git-core. In comparison, the default make build sets it to a relative path equivalent to 'libexec/git-core'. Indeed, the make build requires the use of some means outside of the Makefile (eg. config.mak[.*] or the command-line) to set GIT_EXEC_PATH to anything other than 'libexec/git-core'.

For example, the make invocation:

  $ make gitexecdir=/some/other/bin all install

will build git with GIT_EXEC_PATH set to '/some/other/bin' and install the 'library' executables to that location. However, without setting the 'gitexecdir' make variable, irrespective of the 'runtime prefix' setting, the GIT_EXEC_PATH is always set to 'libexec/git-core'.

The meson built-in 'libexecdir' option can be used to provide a similar configurability. The default value for the option is 'libexec'. Attempting to set the option to '' on the command-line, will reset it to the '.' string, presumably to ensure a relative path value.

This commit allows the meson build, similar to the above, to configure the project like:

  $ meson setup --buildtype=debugoptimized -Dprefix=$HOME -Dpcre2=disabled \
      -Dlibexecdir=/some/other/bin build

so that the GIT_EXEC_PATH is set to '/some/other/bin'. Absent the -Dlibexecdir argument, the GIT_EXEC_PATH is set to 'libexec/git-core'.

In order to correct the value of GIT_EXEC_PATH, default the value to the static string value 'libexec/git-core', and only override if the value of the 'libexecdir' option has a value different to 'libexec' or '.'. Also, like the Makefile, add a check for an absolute path when the runtime prefix option is true (and if so, error out).

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 meson.build | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

Commit f5e3c6c57d ("meson: do a full usage-based compile check for sysinfo", 2025-04-25) updated the 'sysinfo()' check, as part of the meson build, due to the failure of the check on Solaris. Prior to that commit, the meson build only checked the availability of the '<sys/sysinfo.h>' header file. On Solaris, both the header and the 'sysinfo()' function exist, but are completely unrelated to the same function on Linux (and cygwin).

Commit 50dec7c566 ("config.mak.uname: add sysinfo() configuration for cygwin", 2025-04-17) added a similar 'sysinfo()' check to the autoconf build. This check looked for the 'sysinfo()' function itself, rather than just the header, but it will fail (incorrectly set HAVE_SYSINFO) for the same reason.

In order to correctly identify the 'sysinfo()' function we require as part of 'git-gc' (used in the 'total_ram() function), we also upgrade to a compilation check, in a similar way to the meson commit. Note that since commit c9a51775a3 ("builtin/gc.c: correct RAM calculation when using sysinfo", 2025-04-17) both the 'totalram' and 'mem_unit' fields of the 'struct sysinfo' are used, so the new check includes both of those fields in the compile check.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 configure.ac | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

Ramsay Jones <ramsay@ramsayjones.plus.com> writes:

Thanks.

OK. And changes in v4 are just that two redundant comments in the option definitions are removed, which makes sense looking at the discussion from the sidelines.

Will queue.  Are we done with this series by now?

On Mon, May 19, 2025 at 11:48:01AM -0700, Junio C Hamano wrote:

Yup, the range diff looks as expected, so this is ready to go from my point of view. Thanks!

Patrick

On 19/05/2025 20:08, Patrick Steinhardt wrote:

Yes, I think we're good to go.

Also, the 'make test' on cygwin just finished and passed without issue! :)

Thanks.

ATB, Ramsay Jones

Ramsay Jones <ramsay@ramsayjones.plus.com> writes:

Thank you, all!