`should_ignore_subtree_split_commit` detects subtrees which are outside of the current path --prefix and ignores them. This can speed up splits of repositories that have many subtrees. Since its inception [1], every iteration of this logic [2], [3] incorrectly excludes commits. This alters the split history. The split history and its commit hashes are API contract, so this is not permissible. While a commit from a different subtree may look like it doesn't contribute anything to a split, sometimes it does. Merge commits are a particular hot spot. For these, the pruning logic in `copy_or_skip` performs: 1. a check for "treesame" parents 2. two different common ancestry checks These checks operate on the **split history**, not the input history. The split history omits commits that do not affect the --prefix. This can significantly alter the ancestry of a merge. In order to determine if `copy_or_skip` will skip a merge, it is likely necessary to compute all the split history... which is what `should_ignore_subtree_split_commit` tries to avoid. To make this logic API-preserving, we could gate it behind a new CLI argument. The present implementation is actually a speed penalty in many cases, however, so this is not done here. Remove the `should_ignore_subtree_split_commit` logic. This fixes the regression reported in [4]. [1]:98ba49ccc2(subtree: fix split processing with multiple subtrees present, 2023-12-01) [2]:83f9dad7d6(contrib/subtree: fix split with squashed subtrees, 2025-09-09) [3]:28a7e27cff(contrib/subtree: detect rewritten subtree commits, 2026-01-09) [4]: <20251230170719.845029-1-george@mail.dietrich.pub> Reported-by: George <george@mail.dietrich.pub> Reported-by: Christian Heusel <christian@heusel.eu> Signed-off-by: Colin Stagner <ask+git@howdoi.land> 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.adoc to get started, then see
Documentation/giteveryday.adoc for a useful minimum set of commands, and
Documentation/git-<commandname>.adoc 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.adoc
(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