7c78c599bb9b51e5cbdae3e7dc1d723eefcf7c61
4 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
| 45c0897204 |
meson: fix perl dependencies
`generate_perl_command` needs `depends: [git_version_file]` and the uses in top-level meson.build were fine, but the ones in perl/ weren't, causing parallel build failures in some cases as GIT-BUILD-OPTIONS wasn't yet available. Signed-off-by: Sam James <sam@gentoo.org> Acked-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com> |
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| 904339edbd |
Introduce support for the Meson build system
Introduce support for the Meson build system, a "modern" meta build
system that supports many different platforms, including Linux, macOS,
Windows and BSDs. Meson supports different backends, including Ninja,
Xcode and Microsoft Visual Studio. Several common IDEs provide an
integration with it.
The biggest contender compared to Meson is probably CMake as outlined in
our "Documentation/technical/build-systems.txt" file. Based on my own
personal experience from working with both build systems extensively I
strongly favor Meson over CMake. In my opinion, it feels significantly
easier to use with a syntax that feels more like a "real" programming
language. The second big reason is that Meson supports Rust natively,
which may prove to be important given that the project may pick up Rust
as another language eventually.
Using Meson is rather straight-forward. An example:
```
# Meson uses out-of-tree builds. You can set up multiple build
# directories, how you name them is completely up to you.
$ mkdir build
$ cd build
$ meson setup .. -Dprefix=/tmp/git-installation
# Build the project. This also provides several other targets like
e.g. `install` or `test`.
$ ninja
# Meson has been wired up to support execution of our test suites.
# Both our unit tests and our integration tests are supported.
# Running `meson test` without any arguments will execute all tests,
# but the syntax supports globbing to select only some tests.
$ meson test 't-*'
# Execute single test interactively to allow for debugging.
$ meson test 't0000-*' --interactive --test-args=-ix
```
The build instructions have been successfully tested on the following
systems, tests are passing:
- Apple macOS 10.15.
- FreeBSD 14.1.
- NixOS 24.11.
- OpenBSD 7.6.
- Ubuntu 24.04.
- Windows 10 with Cygwin.
- Windows 10 with MinGW64, except for t9700, which is also broken with
our Makefile.
- Windows 10 with Visual Studio 2022 toolchain, using the Native Tools
Command Prompt with `meson setup --vsenv`. Tests pass, except for
t9700.
- Windows 10 with Visual Studio 2022 solution, using the Native Tools
Command Prompt with `meson setup --backend vs2022`. Tests pass,
except for t9700.
- Windows 10 with VS Code, using the Meson plug-in.
It is expected that there will still be rough edges in the current
version. If this patch lands the expectation is that it will coexist
with our other build systems for a while. Like this, distributions can
slowly migrate over to Meson and report any findings they have to us
such that we can continue to iterate. A potential cutoff date for other
build systems may be Git 3.0.
Some notes:
- The installed distribution is structured somewhat differently than
how it used to be the case. All of our binaries are installed into
`$libexec/git-core`, while all binaries part of `$bindir` are now
symbolic links pointing to the former. This rule is consistent in
itself and thus easier to reason about.
- We do not install dashed binaries into `$libexec/git-core` anymore,
so there won't e.g. be a symlink for git-add(1). These are not
required by modern Git and there isn't really much of a use case for
those anymore. By not installing those symlinks we thus start the
deprecation of this layout.
- We're targeting Meson 1.3.0, which has been released relatively
recently November 2023. The only feature we use from that version is
`fs.relative_to()`, which we could replace if necessary. If so, we
could start to target Meson 1.0.0 and newer, released in December
2022.
- The whole build instructions count around 3300 lines, half of which
is listing all of our code and test files. Our Makefiles are around
5000 lines, autoconf adds another 1300 lines. CMake in comparison
has only 1200 linescode, but it avoids listing individual files and
does not wire up auto-configuration as extensively as the Meson
instructions do.
- We bundle a set of subproject wrappers for curl, expat, openssl,
pcre2 and zlib. This allows developers to build Git without these
dependencies preinstalled, and Meson will fetch and build them
automatically. This is especially helpful on Windows.
Helped-by: Eli Schwartz <eschwartz@gentoo.org>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|
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| 5338ed2b26 |
perl: check for perl warnings while running tests
We set "use warnings" in most of our perl code to catch problems. But as the name implies, warnings just emit a message to stderr and don't otherwise affect the program. So our tests are quite likely to miss that warnings are being spewed, as most of them do not look at stderr. We could ask perl to make all warnings fatal, but this is likely annoying for non-developers, who would rather have a running program with a warning than something that refuses to work at all. So instead, let's teach the perl code to respect an environment variable (GIT_PERL_FATAL_WARNINGS) to increase the severity of the warnings. This can be set for day-to-day running if people want to be really pedantic, but the primary use is to trigger it within the test suite. We could also trigger that for every test run, but likewise even the tests failing may be annoying to distro builders, etc (just as -Werror would be for compiling C code). So we'll tie it to a special test-mode variable (GIT_TEST_PERL_FATAL_WARNINGS) that can be set in the environment or as a Makefile knob, and we'll automatically turn the knob when DEVELOPER=1 is set. That should give developers and CI the more careful view without disrupting normal users or packagers. Note that the mapping from the GIT_TEST_* form to the GIT_* form in test-lib.sh is necessary even if they had the same name: the perl scripts need it to be normalized to a perl truth value, and we also have to make sure it's exported (we might have gotten it from the environment, but we might also have gotten it from GIT-BUILD-OPTIONS directly). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com> |
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| 68f532f4ba |
git-svn: use YAML format for mergeinfo cache when possible
Since v1.7.0-rc2~11 (git-svn: persistent memoization, 2010-01-30), git-svn has maintained some private per-repository caches in .git/svn/.caches to avoid refetching and recalculating some mergeinfo-related information with every "git svn fetch". These caches use the 'nstore' format from the perl core module Storable, which can be read and written quickly and was designed for transfer over the wire (the 'n' stands for 'network'). This format is endianness-independent and independent of floating-point representation. Unfortunately the format is *not* independent of the perl version --- new perl versions will write files that very old perl cannot read. Worse, the format is not independent of the size of a perl integer. So if you toggle perl's use64bitint compile-time option, then using 'git svn fetch' on your old repositories produces errors like this: Byte order is not compatible at ../../lib/Storable.pm (autosplit into ../../lib/auto/Storable/_retrieve.al) line 380, at /usr/share/perl/5.12/Memoize/Storable.pm line 21 That is, upgrading perl to a version that uses use64bitint for the first time makes git-svn suddenly refuse to fetch in existing repositories. Removing .git/svn/.caches lets git-svn recover. It's time to switch to a platform independent serializer backend with better compatibility guarantees. This patch uses YAML::Any. Other choices were considered: - thawing data from Data::Dumper involves "eval". Doing that without creating a security risk is fussy. - the JSON API works on scalars in memory and doesn't provide a standard way to serialize straight to disk. YAML::Any is reasonably fast and has a pleasant API. In most backends, LoadFile() reads the entire file into a scalar anyway and converts it as a second step, but having an interface that allows the deserialization to happen on the fly without a temporary is still a comfort. YAML::Any is not a core perl module, so we take care to use it when and only when it is available. Installations without that module should fall back to using Storable with all its quirks, keeping their cache files in .git/svn/.caches/*.db Installations with YAML peacefully coexist by keeping a separate set of cache files in .git/svn/.caches/*.yaml. In most cases, switching between is a one-time thing, so it doesn't seem worth the complication to migrate existing caches. The upshot: after this patch, as long as YAML::Any is installed you can move your git repository between machines with different perl installations and "git svn fetch" will work fine. If you do not have YAML::Any, the behavior is unchanged (and in particular does not get any worse). Reported-by: Sandro Weiser <sandro.weiser@informatik.tu-chemnitz.de> Reported-by: Bdale Garbee <bdale@gag.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Eric Wong <normalperson@yhbt.net> |
