In 03267e8656c (commit: discard partial cache before (re-)reading it, 2022-11-08), a memory leak was plugged by discarding any partial index before re-reading it. The problem with this memory leak fix is that it was based on an incomplete understanding of the logic introduced in 7168624c353 (Do not generate full commit log message if it is not going to be used, 2007-11-28). That logic was introduced to add a shortcut when committing without editing the commit message interactively. A part of that logic was to ensure that the index was read into memory: if (!active_nr && read_cache() < 0) die(...) Translation to English: If the index has not yet been read, read it, and if that fails, error out. That logic was incorrect, though: It used `!active_nr` as an indicator that the index was not yet read. Usually this is not a problem because in the vast majority of instances, the index contains at least one entry. And it was natural to do it this way because at the time that condition was introduced, the `index_state` structure had no explicit flag to indicate that it was initialized: This flag was only introduced in 913e0e99b6a (unpack_trees(): protect the handcrafted in-core index from read_cache(), 2008-08-23), but that commit did not adjust the code path where no index file was found and a new, pristine index was initialized. Now, when the index does not contain any entry (which is quite common in Git's test suite because it starts quite a many repositories from scratch), subsequent calls to `do_read_index()` will mistake the index not to be initialized, and read it again unnecessarily. This is a problem because after initializing the empty index e.g. the `cache_tree` in that index could have been initialized before a subsequent call to `do_read_index()` wants to ensure an initialized index. And if that subsequent call mistakes the index not to have been initialized, it would lead to leaked memory. The correct fix for that memory leak is to adjust the condition so that it does not mistake `active_nr == 0` to mean that the index has not yet been read. Using the `initialized` flag instead, we avoid that mistake, and as a bonus we can fix a bug at the same time that was introduced by the memory leak fix: When deleting all tracked files and then asking `git commit -a -m ...` to commit the result, Git would internally update the index, then discard and re-read the index undoing the update, and fail to commit anything. This fixes https://github.com/git-for-windows/git/issues/4462 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> 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 with just "subscribe git" in the body to majordomo@vger.kernel.org (not the Git list). The mailing list archives are available at https://lore.kernel.org/git/, http://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