992bc5618f
GIT-VERSION-GEN tries to derive the version that Git is being built from
via multiple different sources in the following order:
1. A file called "version" in the source tree's root directory, if it
exists.
2. The current commit in case Git is built from a Git repository.
3. Otherwise, we use a fallback version stored in a variable which is
bumped whenever a new Git version is getting tagged.
It used to be possible to override the version by overriding the
`GIT_VERSION` Makefile variable (e.g. `make GIT_VERSION=foo`). This
worked somewhat by chance, only: `GIT-VERSION-GEN` would write the
actual Git version into `GIT-VERSION-FILE`, not the overridden value,
but when including the file into our Makefile we would not override the
`GIT_VERSION` variable because it has already been set by the user. And
because our Makefile used the variable to propagate the version to our
build tools instead of using `GIT-VERSION-FILE` the resulting build
artifacts used the overridden version.
But that subtle mechanism broke with 4838deab65 (Makefile: refactor
GIT-VERSION-GEN to be reusable, 2024-12-06) and subsequent commits
because the version information is not propagated via the Makefile
variable anymore, but instead via the files that `GIT-VERSION-GEN`
started to write. And as the script never knew about the `GIT_VERSION`
environment variable in the first place it uses one of the values listed
above instead of the overridden value.
Fix this issue by making `GIT-VERSION-GEN` handle the case where
`GIT_VERSION` has been set via the environment.
Note that this requires us to introduce a new GIT_VERSION_OVERRIDE
variable that stores a potential user-provided value, either via the
environment or via "config.mak". Ideally we wouldn't need it and could
just continue to use GIT_VERSION for this. But unfortunately, Makefiles
will first include all sub-Makefiles before figuring out whether it
needs to re-make any of them [1]. Consequently, if there already is a
GIT-VERSION-FILE, we would have slurped in its value of GIT_VERSION
before we call GIT-VERSION-GEN, and because GIT-VERSION-GEN now uses
that value as an override it would mean that the first generated value
for GIT_VERSION will remain unchanged.
Furthermore we have to move the include for "GIT-VERSION-FILE" after the
includes for "config.mak" and related so that GIT_VERSION_OVERRIDE can
be set to the value provided by "config.mak".
[1]: https://www.gnu.org/software/make/manual/html_node/Remaking-Makefiles.html
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission and Documentation/CodingGuidelines).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks