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GIT-REBASE(1) Git Manual GIT-REBASE(1)
git-rebase - Reapply commits on top of another base tip
git rebase [-i | --interactive] [<options>] [--exec <cmd>]
[--onto <newbase> | --keep-base] [<upstream> [<branch>]]
git rebase [-i | --interactive] [<options>] [--exec <cmd>] [--onto <newbase>]
--root [<branch>]
git rebase (--continue|--skip|--abort|--quit|--edit-todo|--show-current-patch)
If <branch> is specified, git rebase will perform an automatic
git switch <branch> before doing anything else. Otherwise it
remains on the current branch.
If <upstream> is not specified, the upstream configured in
branch.<name>.remote and branch.<name>.merge options will be used
(see git-config(1) for details) and the --fork-point option is
assumed. If you are currently not on any branch or if the current
branch does not have a configured upstream, the rebase will
abort.
All changes made by commits in the current branch but that are
not in <upstream> are saved to a temporary area. This is the same
set of commits that would be shown by git log <upstream>..HEAD;
or by git log 'fork_point'..HEAD, if --fork-point is active (see
the description on --fork-point below); or by git log HEAD, if
the --root option is specified.
The current branch is reset to <upstream> or <newbase> if the
--onto option was supplied. This has the exact same effect as git
reset --hard <upstream> (or <newbase>). ORIG_HEAD is set to point
at the tip of the branch before the reset.
Note
ORIG_HEAD is not guaranteed to still point to the previous
branch tip at the end of the rebase if other commands that
write that pseudo-ref (e.g. git reset) are used during the
rebase. The previous branch tip, however, is accessible using
the reflog of the current branch (i.e. @{1}, see
gitrevisions(7)).
The commits that were previously saved into the temporary area
are then reapplied to the current branch, one by one, in order.
Note that any commits in HEAD which introduce the same textual
changes as a commit in HEAD..<upstream> are omitted (i.e., a
patch already accepted upstream with a different commit message
or timestamp will be skipped).
It is possible that a merge failure will prevent this process
from being completely automatic. You will have to resolve any
such merge failure and run git rebase --continue. Another option
is to bypass the commit that caused the merge failure with git
rebase --skip. To check out the original <branch> and remove the
.git/rebase-apply working files, use the command git rebase
--abort instead.
Assume the following history exists and the current branch is
"topic":
A---B---C topic
/
D---E---F---G master
From this point, the result of either of the following commands:
git rebase master
git rebase master topic
would be:
A'--B'--C' topic
/
D---E---F---G master
NOTE: The latter form is just a short-hand of git checkout topic
followed by git rebase master. When rebase exits topic will
remain the checked-out branch.
If the upstream branch already contains a change you have made
(e.g., because you mailed a patch which was applied upstream),
then that commit will be skipped and warnings will be issued (if
the merge backend is used). For example, running git rebase
master on the following history (in which A' and A introduce the
same set of changes, but have different committer information):
A---B---C topic
/
D---E---A'---F master
will result in:
B'---C' topic
/
D---E---A'---F master
Here is how you would transplant a topic branch based on one
branch to another, to pretend that you forked the topic branch
from the latter branch, using rebase --onto.
First let’s assume your topic is based on branch next. For
example, a feature developed in topic depends on some
functionality which is found in next.
o---o---o---o---o master
\
o---o---o---o---o next
\
o---o---o topic
We want to make topic forked from branch master; for example,
because the functionality on which topic depends was merged into
the more stable master branch. We want our tree to look like
this:
o---o---o---o---o master
| \
| o'--o'--o' topic
\
o---o---o---o---o next
We can get this using the following command:
git rebase --onto master next topic
Another example of --onto option is to rebase part of a branch.
If we have the following situation:
H---I---J topicB
/
E---F---G topicA
/
A---B---C---D master
then the command
git rebase --onto master topicA topicB
would result in:
H'--I'--J' topicB
/
| E---F---G topicA
|/
A---B---C---D master
This is useful when topicB does not depend on topicA.
A range of commits could also be removed with rebase. If we have
the following situation:
E---F---G---H---I---J topicA
then the command
git rebase --onto topicA~5 topicA~3 topicA
would result in the removal of commits F and G:
E---H'---I'---J' topicA
This is useful if F and G were flawed in some way, or should not
be part of topicA. Note that the argument to --onto and the
<upstream> parameter can be any valid commit-ish.
In case of conflict, git rebase will stop at the first
problematic commit and leave conflict markers in the tree. You
can use git diff to locate the markers (<<<<<<) and make edits to
resolve the conflict. For each file you edit, you need to tell
Git that the conflict has been resolved, typically this would be
done with
git add <filename>
After resolving the conflict manually and updating the index with
the desired resolution, you can continue the rebasing process
with
git rebase --continue
Alternatively, you can undo the git rebase with
git rebase --abort
The options in this section cannot be used with any other option,
including not with each other:
--continue
Restart the rebasing process after having resolved a merge
conflict.
--skip
Restart the rebasing process by skipping the current patch.
--abort
Abort the rebase operation and reset HEAD to the original
branch. If <branch> was provided when the rebase operation
was started, then HEAD will be reset to <branch>. Otherwise
HEAD will be reset to where it was when the rebase operation
was started.
--quit
Abort the rebase operation but HEAD is not reset back to the
original branch. The index and working tree are also left
unchanged as a result. If a temporary stash entry was created
using --autostash, it will be saved to the stash list.
--edit-todo
Edit the todo list during an interactive rebase.
--show-current-patch
Show the current patch in an interactive rebase or when
rebase is stopped because of conflicts. This is the
equivalent of git show REBASE_HEAD.
--onto <newbase>
Starting point at which to create the new commits. If the
--onto option is not specified, the starting point is
<upstream>. May be any valid commit, and not just an existing
branch name.
As a special case, you may use "A...B" as a shortcut for the
merge base of A and B if there is exactly one merge base. You
can leave out at most one of A and B, in which case it
defaults to HEAD.
--keep-base
Set the starting point at which to create the new commits to
the merge base of <upstream> and <branch>. Running git rebase
--keep-base <upstream> <branch> is equivalent to running git
rebase --reapply-cherry-picks --no-fork-point --onto
<upstream>...<branch> <upstream> <branch>.
This option is useful in the case where one is developing a
feature on top of an upstream branch. While the feature is
being worked on, the upstream branch may advance and it may
not be the best idea to keep rebasing on top of the upstream
but to keep the base commit as-is. As the base commit is
unchanged this option implies --reapply-cherry-picks to avoid
losing commits.
Although both this option and --fork-point find the merge
base between <upstream> and <branch>, this option uses the
merge base as the starting point on which new commits will be
created, whereas --fork-point uses the merge base to
determine the set of commits which will be rebased.
See also INCOMPATIBLE OPTIONS below.
<upstream>
Upstream branch to compare against. May be any valid commit,
not just an existing branch name. Defaults to the configured
upstream for the current branch.
<branch>
Working branch; defaults to HEAD.
--apply
Use applying strategies to rebase (calling git-am
internally). This option may become a no-op in the future
once the merge backend handles everything the apply one does.
See also INCOMPATIBLE OPTIONS below.
--empty=(drop|keep|stop)
How to handle commits that are not empty to start and are not
clean cherry-picks of any upstream commit, but which become
empty after rebasing (because they contain a subset of
already upstream changes):
drop
The commit will be dropped. This is the default behavior.
keep
The commit will be kept. This option is implied when
--exec is specified unless -i/--interactive is also
specified.
stop, ask
The rebase will halt when the commit is applied, allowing
you to choose whether to drop it, edit files more, or
just commit the empty changes. This option is implied
when -i/--interactive is specified. ask is a deprecated
synonym of stop.
Note that commits which start empty are kept (unless
--no-keep-empty is specified), and commits which are clean
cherry-picks (as determined by git log --cherry-mark ...) are
detected and dropped as a preliminary step (unless
--reapply-cherry-picks or --keep-base is passed).
See also INCOMPATIBLE OPTIONS below.
--no-keep-empty, --keep-empty
Do not keep commits that start empty before the rebase (i.e.
that do not change anything from its parent) in the result.
The default is to keep commits which start empty, since
creating such commits requires passing the --allow-empty
override flag to git commit, signifying that a user is very
intentionally creating such a commit and thus wants to keep
it.
Usage of this flag will probably be rare, since you can get
rid of commits that start empty by just firing up an
interactive rebase and removing the lines corresponding to
the commits you don’t want. This flag exists as a convenient
shortcut, such as for cases where external tools generate
many empty commits and you want them all removed.
For commits which do not start empty but become empty after
rebasing, see the --empty flag.
See also INCOMPATIBLE OPTIONS below.
--reapply-cherry-picks, --no-reapply-cherry-picks
Reapply all clean cherry-picks of any upstream commit instead
of preemptively dropping them. (If these commits then become
empty after rebasing, because they contain a subset of
already upstream changes, the behavior towards them is
controlled by the --empty flag.)
In the absence of --keep-base (or if
--no-reapply-cherry-picks is given), these commits will be
automatically dropped. Because this necessitates reading all
upstream commits, this can be expensive in repositories with
a large number of upstream commits that need to be read. When
using the merge backend, warnings will be issued for each
dropped commit (unless --quiet is given). Advice will also be
issued unless advice.skippedCherryPicks is set to false (see
git-config(1)).
--reapply-cherry-picks allows rebase to forgo reading all
upstream commits, potentially improving performance.
See also INCOMPATIBLE OPTIONS below.
--allow-empty-message
No-op. Rebasing commits with an empty message used to fail
and this option would override that behavior, allowing
commits with empty messages to be rebased. Now commits with
an empty message do not cause rebasing to halt.
See also INCOMPATIBLE OPTIONS below.
-m, --merge
Using merging strategies to rebase (default).
Note that a rebase merge works by replaying each commit from
the working branch on top of the <upstream> branch. Because
of this, when a merge conflict happens, the side reported as
ours is the so-far rebased series, starting with <upstream>,
and theirs is the working branch. In other words, the sides
are swapped.
See also INCOMPATIBLE OPTIONS below.
-s <strategy>, --strategy=<strategy>
Use the given merge strategy, instead of the default ort.
This implies --merge.
Because git rebase replays each commit from the working
branch on top of the <upstream> branch using the given
strategy, using the ours strategy simply empties all patches
from the <branch>, which makes little sense.
See also INCOMPATIBLE OPTIONS below.
-X <strategy-option>, --strategy-option=<strategy-option>
Pass the <strategy-option> through to the merge strategy.
This implies --merge and, if no strategy has been specified,
-s ort. Note the reversal of ours and theirs as noted above
for the -m option.
See also INCOMPATIBLE OPTIONS below.
--rerere-autoupdate, --no-rerere-autoupdate
After the rerere mechanism reuses a recorded resolution on
the current conflict to update the files in the working tree,
allow it to also update the index with the result of
resolution. --no-rerere-autoupdate is a good way to
double-check what rerere did and catch potential mismerges,
before committing the result to the index with a separate git
add.
-S[<keyid>], --gpg-sign[=<keyid>], --no-gpg-sign
GPG-sign commits. The keyid argument is optional and defaults
to the committer identity; if specified, it must be stuck to
the option without a space. --no-gpg-sign is useful to
countermand both commit.gpgSign configuration variable, and
earlier --gpg-sign.
-q, --quiet
Be quiet. Implies --no-stat.
-v, --verbose
Be verbose. Implies --stat.
--stat
Show a diffstat of what changed upstream since the last
rebase. The diffstat is also controlled by the configuration
option rebase.stat.
-n, --no-stat
Do not show a diffstat as part of the rebase process.
--no-verify
This option bypasses the pre-rebase hook. See also
githooks(5).
--verify
Allows the pre-rebase hook to run, which is the default. This
option can be used to override --no-verify. See also
githooks(5).
-C<n>
Ensure at least <n> lines of surrounding context match before
and after each change. When fewer lines of surrounding
context exist they all must match. By default no context is
ever ignored. Implies --apply.
See also INCOMPATIBLE OPTIONS below.
--no-ff, --force-rebase, -f
Individually replay all rebased commits instead of
fast-forwarding over the unchanged ones. This ensures that
the entire history of the rebased branch is composed of new
commits.
You may find this helpful after reverting a topic branch
merge, as this option recreates the topic branch with fresh
commits so it can be remerged successfully without needing to
"revert the reversion" (see the revert-a-faulty-merge
How-To[1] for details).
--fork-point, --no-fork-point
Use reflog to find a better common ancestor between
<upstream> and <branch> when calculating which commits have
been introduced by <branch>.
When --fork-point is active, fork_point will be used instead
of <upstream> to calculate the set of commits to rebase,
where fork_point is the result of git merge-base --fork-point
<upstream> <branch> command (see git-merge-base(1)). If
fork_point ends up being empty, the <upstream> will be used
as a fallback.
If <upstream> or --keep-base is given on the command line,
then the default is --no-fork-point, otherwise the default is
--fork-point. See also rebase.forkpoint in git-config(1).
If your branch was based on <upstream> but <upstream> was
rewound and your branch contains commits which were dropped,
this option can be used with --keep-base in order to drop
those commits from your branch.
See also INCOMPATIBLE OPTIONS below.
--ignore-whitespace
Ignore whitespace differences when trying to reconcile
differences. Currently, each backend implements an
approximation of this behavior:
apply backend
When applying a patch, ignore changes in whitespace in
context lines. Unfortunately, this means that if the
"old" lines being replaced by the patch differ only in
whitespace from the existing file, you will get a merge
conflict instead of a successful patch application.
merge backend
Treat lines with only whitespace changes as unchanged
when merging. Unfortunately, this means that any patch
hunks that were intended to modify whitespace and nothing
else will be dropped, even if the other side had no
changes that conflicted.
--whitespace=<option>
This flag is passed to the git apply program (see
git-apply(1)) that applies the patch. Implies --apply.
See also INCOMPATIBLE OPTIONS below.
--committer-date-is-author-date
Instead of using the current time as the committer date, use
the author date of the commit being rebased as the committer
date. This option implies --force-rebase.
--ignore-date, --reset-author-date
Instead of using the author date of the original commit, use
the current time as the author date of the rebased commit.
This option implies --force-rebase.
See also INCOMPATIBLE OPTIONS below.
--signoff
Add a Signed-off-by trailer to all the rebased commits. Note
that if --interactive is given then only commits marked to be
picked, edited or reworded will have the trailer added.
See also INCOMPATIBLE OPTIONS below.
-i, --interactive
Make a list of the commits which are about to be rebased. Let
the user edit that list before rebasing. This mode can also
be used to split commits (see SPLITTING COMMITS below).
The commit list format can be changed by setting the
configuration option rebase.instructionFormat. A customized
instruction format will automatically have the commit hash
prepended to the format.
See also INCOMPATIBLE OPTIONS below.
-r, --rebase-merges[=(rebase-cousins|no-rebase-cousins)],
--no-rebase-merges
By default, a rebase will simply drop merge commits from the
todo list, and put the rebased commits into a single, linear
branch. With --rebase-merges, the rebase will instead try to
preserve the branching structure within the commits that are
to be rebased, by recreating the merge commits. Any resolved
merge conflicts or manual amendments in these merge commits
will have to be resolved/re-applied manually.
--no-rebase-merges can be used to countermand both the
rebase.rebaseMerges config option and a previous
--rebase-merges.
When rebasing merges, there are two modes: rebase-cousins and
no-rebase-cousins. If the mode is not specified, it defaults
to no-rebase-cousins. In no-rebase-cousins mode, commits
which do not have <upstream> as direct ancestor will keep
their original branch point, i.e. commits that would be
excluded by git-log(1)'s --ancestry-path option will keep
their original ancestry by default. In rebase-cousins mode,
such commits are instead rebased onto <upstream> (or <onto>,
if specified).
It is currently only possible to recreate the merge commits
using the ort merge strategy; different merge strategies can
be used only via explicit exec git merge -s <strategy> [...]
commands.
See also REBASING MERGES and INCOMPATIBLE OPTIONS below.
-x <cmd>, --exec <cmd>
Append "exec <cmd>" after each line creating a commit in the
final history. <cmd> will be interpreted as one or more
shell commands. Any command that fails will interrupt the
rebase, with exit code 1.
You may execute several commands by either using one instance
of --exec with several commands:
git rebase -i --exec "cmd1 && cmd2 && ..."
or by giving more than one --exec:
git rebase -i --exec "cmd1" --exec "cmd2" --exec ...
If --autosquash is used, exec lines will not be appended for
the intermediate commits, and will only appear at the end of
each squash/fixup series.
This uses the --interactive machinery internally, but it can
be run without an explicit --interactive.
See also INCOMPATIBLE OPTIONS below.
--root
Rebase all commits reachable from <branch>, instead of
limiting them with an <upstream>. This allows you to rebase
the root commit(s) on a branch.
See also INCOMPATIBLE OPTIONS below.
--autosquash, --no-autosquash
Automatically squash commits with specially formatted
messages into previous commits being rebased. If a commit
message starts with "squash! ", "fixup! " or "amend! ", the
remainder of the subject line is taken as a commit specifier,
which matches a previous commit if it matches the subject
line or the hash of that commit. If no commit matches fully,
matches of the specifier with the start of commit subjects
are considered.
In the rebase todo list, the actions of squash, fixup and
amend commits are changed from pick to squash, fixup or fixup
-C, respectively, and they are moved right after the commit
they modify. The --interactive option can be used to review
and edit the todo list before proceeding.
The recommended way to create commits with squash markers is
by using the --squash, --fixup, --fixup=amend: or
--fixup=reword: options of git-commit(1), which take the
target commit as an argument and automatically fill in the
subject line of the new commit from that.
Setting configuration variable rebase.autoSquash to true
enables auto-squashing by default for interactive rebase. The
--no-autosquash option can be used to override that setting.
See also INCOMPATIBLE OPTIONS below.
--autostash, --no-autostash
Automatically create a temporary stash entry before the
operation begins, and apply it after the operation ends. This
means that you can run rebase on a dirty worktree. However,
use with care: the final stash application after a successful
rebase might result in non-trivial conflicts.
--reschedule-failed-exec, --no-reschedule-failed-exec
Automatically reschedule exec commands that failed. This only
makes sense in interactive mode (or when an --exec option was
provided).
This option applies once a rebase is started. It is preserved
for the whole rebase based on, in order, the command line
option provided to the initial git rebase, the
rebase.rescheduleFailedExec configuration (see git-config(1)
or "CONFIGURATION" below), or it defaults to false.
Recording this option for the whole rebase is a convenience
feature. Otherwise an explicit --no-reschedule-failed-exec at
the start would be overridden by the presence of a
rebase.rescheduleFailedExec=true configuration when git
rebase --continue is invoked. Currently, you cannot pass
--[no-]reschedule-failed-exec to git rebase --continue.
--update-refs, --no-update-refs
Automatically force-update any branches that point to commits
that are being rebased. Any branches that are checked out in
a worktree are not updated in this way.
If the configuration variable rebase.updateRefs is set, then
this option can be used to override and disable this setting.
See also INCOMPATIBLE OPTIONS below.
The following options:
• --apply
• --whitespace
• -C
are incompatible with the following options:
• --merge
• --strategy
• --strategy-option
• --autosquash
• --rebase-merges
• --interactive
• --exec
• --no-keep-empty
• --empty=
• --[no-]reapply-cherry-picks when used without --keep-base
• --update-refs
• --root when used without --onto
In addition, the following pairs of options are incompatible:
• --keep-base and --onto
• --keep-base and --root
• --fork-point and --root
git rebase has two primary backends: apply and merge. (The apply
backend used to be known as the am backend, but the name led to
confusion as it looks like a verb instead of a noun. Also, the
merge backend used to be known as the interactive backend, but it
is now used for non-interactive cases as well. Both were renamed
based on lower-level functionality that underpinned each.) There
are some subtle differences in how these two backends behave:
Empty commits
The apply backend unfortunately drops intentionally empty
commits, i.e. commits that started empty, though these are rare
in practice. It also drops commits that become empty and has no
option for controlling this behavior.
The merge backend keeps intentionally empty commits by default
(though with -i they are marked as empty in the todo list editor,
or they can be dropped automatically with --no-keep-empty).
Similar to the apply backend, by default the merge backend drops
commits that become empty unless -i/--interactive is specified
(in which case it stops and asks the user what to do). The merge
backend also has an --empty=(drop|keep|stop) option for changing
the behavior of handling commits that become empty.
Directory rename detection
Due to the lack of accurate tree information (arising from
constructing fake ancestors with the limited information
available in patches), directory rename detection is disabled in
the apply backend. Disabled directory rename detection means that
if one side of history renames a directory and the other adds new
files to the old directory, then the new files will be left
behind in the old directory without any warning at the time of
rebasing that you may want to move these files into the new
directory.
Directory rename detection works with the merge backend to
provide you warnings in such cases.
Context
The apply backend works by creating a sequence of patches (by
calling format-patch internally), and then applying the patches
in sequence (calling am internally). Patches are composed of
multiple hunks, each with line numbers, a context region, and the
actual changes. The line numbers have to be taken with some fuzz,
since the other side will likely have inserted or deleted lines
earlier in the file. The context region is meant to help find how
to adjust the line numbers in order to apply the changes to the
right lines. However, if multiple areas of the code have the same
surrounding lines of context, the wrong one can be picked. There
are real-world cases where this has caused commits to be
reapplied incorrectly with no conflicts reported. Setting
diff.context to a larger value may prevent such types of
problems, but increases the chance of spurious conflicts (since
it will require more lines of matching context to apply).
The merge backend works with a full copy of each relevant file,
insulating it from these types of problems.
Labelling of conflicts markers
When there are content conflicts, the merge machinery tries to
annotate each side’s conflict markers with the commits where the
content came from. Since the apply backend drops the original
information about the rebased commits and their parents (and
instead generates new fake commits based off limited information
in the generated patches), those commits cannot be identified;
instead it has to fall back to a commit summary. Also, when
merge.conflictStyle is set to diff3 or zdiff3, the apply backend
will use "constructed merge base" to label the content from the
merge base, and thus provide no information about the merge base
commit whatsoever.
The merge backend works with the full commits on both sides of
history and thus has no such limitations.
Hooks
The apply backend has not traditionally called the post-commit
hook, while the merge backend has. Both have called the
post-checkout hook, though the merge backend has squelched its
output. Further, both backends only call the post-checkout hook
with the starting point commit of the rebase, not the
intermediate commits nor the final commit. In each case, the
calling of these hooks was by accident of implementation rather
than by design (both backends were originally implemented as
shell scripts and happened to invoke other commands like git
checkout or git commit that would call the hooks). Both backends
should have the same behavior, though it is not entirely clear
which, if any, is correct. We will likely make rebase stop
calling either of these hooks in the future.
Interruptability
The apply backend has safety problems with an ill-timed
interrupt; if the user presses Ctrl-C at the wrong time to try to
abort the rebase, the rebase can enter a state where it cannot be
aborted with a subsequent git rebase --abort. The merge backend
does not appear to suffer from the same shortcoming. (See
https://lore.kernel.org/git/[email protected]/ for
details.)
Commit Rewording
When a conflict occurs while rebasing, rebase stops and asks the
user to resolve. Since the user may need to make notable changes
while resolving conflicts, after conflicts are resolved and the
user has run git rebase --continue, the rebase should open an
editor and ask the user to update the commit message. The merge
backend does this, while the apply backend blindly applies the
original commit message.
Miscellaneous differences
There are a few more behavioral differences that most folks would
probably consider inconsequential but which are mentioned for
completeness:
• Reflog: The two backends will use different wording when
describing the changes made in the reflog, though both will
make use of the word "rebase".
• Progress, informational, and error messages: The two backends
provide slightly different progress and informational
messages. Also, the apply backend writes error messages (such
as "Your files would be overwritten...") to stdout, while the
merge backend writes them to stderr.
• State directories: The two backends keep their state in
different directories under .git/
The merge mechanism (git merge and git pull commands) allows the
backend merge strategies to be chosen with -s option. Some
strategies can also take their own options, which can be passed
by giving -X<option> arguments to git merge and/or git pull.
ort
This is the default merge strategy when pulling or merging
one branch. This strategy can only resolve two heads using a
3-way merge algorithm. When there is more than one common
ancestor that can be used for 3-way merge, it creates a
merged tree of the common ancestors and uses that as the
reference tree for the 3-way merge. This has been reported to
result in fewer merge conflicts without causing mismerges by
tests done on actual merge commits taken from Linux 2.6
kernel development history. Additionally this strategy can
detect and handle merges involving renames. It does not make
use of detected copies. The name for this algorithm is an
acronym ("Ostensibly Recursive’s Twin") and came from the
fact that it was written as a replacement for the previous
default algorithm, recursive.
The ort strategy can take the following options:
ours
This option forces conflicting hunks to be auto-resolved
cleanly by favoring our version. Changes from the other
tree that do not conflict with our side are reflected in
the merge result. For a binary file, the entire contents
are taken from our side.
This should not be confused with the ours merge strategy,
which does not even look at what the other tree contains
at all. It discards everything the other tree did,
declaring our history contains all that happened in it.
theirs
This is the opposite of ours; note that, unlike ours,
there is no theirs merge strategy to confuse this merge
option with.
ignore-space-change, ignore-all-space, ignore-space-at-eol,
ignore-cr-at-eol
Treats lines with the indicated type of whitespace change
as unchanged for the sake of a three-way merge.
Whitespace changes mixed with other changes to a line are
not ignored. See also git-diff(1) -b, -w,
--ignore-space-at-eol, and --ignore-cr-at-eol.
• If their version only introduces whitespace changes
to a line, our version is used;
• If our version introduces whitespace changes but
their version includes a substantial change, their
version is used;
• Otherwise, the merge proceeds in the usual way.
renormalize
This runs a virtual check-out and check-in of all three
stages of a file when resolving a three-way merge. This
option is meant to be used when merging branches with
different clean filters or end-of-line normalization
rules. See "Merging branches with differing
checkin/checkout attributes" in gitattributes(5) for
details.
no-renormalize
Disables the renormalize option. This overrides the
merge.renormalize configuration variable.
find-renames[=<n>]
Turn on rename detection, optionally setting the
similarity threshold. This is the default. This overrides
the merge.renames configuration variable. See also
git-diff(1) --find-renames.
rename-threshold=<n>
Deprecated synonym for find-renames=<n>.
subtree[=<path>]
This option is a more advanced form of subtree strategy,
where the strategy makes a guess on how two trees must be
shifted to match with each other when merging. Instead,
the specified path is prefixed (or stripped from the
beginning) to make the shape of two trees to match.
recursive
This can only resolve two heads using a 3-way merge
algorithm. When there is more than one common ancestor that
can be used for 3-way merge, it creates a merged tree of the
common ancestors and uses that as the reference tree for the
3-way merge. This has been reported to result in fewer merge
conflicts without causing mismerges by tests done on actual
merge commits taken from Linux 2.6 kernel development
history. Additionally this can detect and handle merges
involving renames. It does not make use of detected copies.
This was the default strategy for resolving two heads from
Git v0.99.9k until v2.33.0.
The recursive strategy takes the same options as ort.
However, there are three additional options that ort ignores
(not documented above) that are potentially useful with the
recursive strategy:
patience
Deprecated synonym for diff-algorithm=patience.
diff-algorithm=[patience|minimal|histogram|myers]
Use a different diff algorithm while merging, which can
help avoid mismerges that occur due to unimportant
matching lines (such as braces from distinct functions).
See also git-diff(1) --diff-algorithm. Note that ort
specifically uses diff-algorithm=histogram, while
recursive defaults to the diff.algorithm config setting.
no-renames
Turn off rename detection. This overrides the
merge.renames configuration variable. See also
git-diff(1) --no-renames.
resolve
This can only resolve two heads (i.e. the current branch and
another branch you pulled from) using a 3-way merge
algorithm. It tries to carefully detect criss-cross merge
ambiguities. It does not handle renames.
octopus
This resolves cases with more than two heads, but refuses to
do a complex merge that needs manual resolution. It is
primarily meant to be used for bundling topic branch heads
together. This is the default merge strategy when pulling or
merging more than one branch.
ours
This resolves any number of heads, but the resulting tree of
the merge is always that of the current branch head,
effectively ignoring all changes from all other branches. It
is meant to be used to supersede old development history of
side branches. Note that this is different from the -Xours
option to the recursive merge strategy.
subtree
This is a modified ort strategy. When merging trees A and B,
if B corresponds to a subtree of A, B is first adjusted to
match the tree structure of A, instead of reading the trees
at the same level. This adjustment is also done to the common
ancestor tree.
With the strategies that use 3-way merge (including the default,
ort), if a change is made on both branches, but later reverted on
one of the branches, that change will be present in the merged
result; some people find this behavior confusing. It occurs
because only the heads and the merge base are considered when
performing a merge, not the individual commits. The merge
algorithm therefore considers the reverted change as no change at
all, and substitutes the changed version instead.
You should understand the implications of using git rebase on a
repository that you share. See also RECOVERING FROM UPSTREAM
REBASE below.
When the rebase is run, it will first execute a pre-rebase hook
if one exists. You can use this hook to do sanity checks and
reject the rebase if it isn’t appropriate. Please see the
template pre-rebase hook script for an example.
Upon completion, <branch> will be the current branch.
Rebasing interactively means that you have a chance to edit the
commits which are rebased. You can reorder the commits, and you
can remove them (weeding out bad or otherwise unwanted patches).
The interactive mode is meant for this type of workflow:
1. have a wonderful idea
2. hack on the code
3. prepare a series for submission
4. submit
where point 2. consists of several instances of
a) regular use
1. finish something worthy of a commit
2. commit
b) independent fixup
1. realize that something does not work
2. fix that
3. commit it
Sometimes the thing fixed in b.2. cannot be amended to the
not-quite perfect commit it fixes, because that commit is buried
deeply in a patch series. That is exactly what interactive rebase
is for: use it after plenty of "a"s and "b"s, by rearranging and
editing commits, and squashing multiple commits into one.
Start it with the last commit you want to retain as-is:
git rebase -i <after-this-commit>
An editor will be fired up with all the commits in your current
branch (ignoring merge commits), which come after the given
commit. You can reorder the commits in this list to your heart’s
content, and you can remove them. The list looks more or less
like this:
pick deadbee The oneline of this commit
pick fa1afe1 The oneline of the next commit
...
The oneline descriptions are purely for your pleasure; git rebase
will not look at them but at the commit names ("deadbee" and
"fa1afe1" in this example), so do not delete or edit the names.
By replacing the command "pick" with the command "edit", you can
tell git rebase to stop after applying that commit, so that you
can edit the files and/or the commit message, amend the commit,
and continue rebasing.
To interrupt the rebase (just like an "edit" command would do,
but without cherry-picking any commit first), use the "break"
command.
If you just want to edit the commit message for a commit, replace
the command "pick" with the command "reword".
To drop a commit, replace the command "pick" with "drop", or just
delete the matching line.
If you want to fold two or more commits into one, replace the
command "pick" for the second and subsequent commits with
"squash" or "fixup". If the commits had different authors, the
folded commit will be attributed to the author of the first
commit. The suggested commit message for the folded commit is the
concatenation of the first commit’s message with those identified
by "squash" commands, omitting the messages of commits identified
by "fixup" commands, unless "fixup -c" is used. In that case the
suggested commit message is only the message of the "fixup -c"
commit, and an editor is opened allowing you to edit the message.
The contents (patch) of the "fixup -c" commit are still
incorporated into the folded commit. If there is more than one
"fixup -c" commit, the message from the final one is used. You
can also use "fixup -C" to get the same behavior as "fixup -c"
except without opening an editor.
git rebase will stop when "pick" has been replaced with "edit" or
when a command fails due to merge errors. When you are done
editing and/or resolving conflicts you can continue with git
rebase --continue.
For example, if you want to reorder the last 5 commits, such that
what was HEAD~4 becomes the new HEAD. To achieve that, you would
call git rebase like this:
$ git rebase -i HEAD~5
And move the first patch to the end of the list.
You might want to recreate merge commits, e.g. if you have a
history like this:
X
\
A---M---B
/
---o---O---P---Q
Suppose you want to rebase the side branch starting at "A" to
"Q". Make sure that the current HEAD is "B", and call
$ git rebase -i -r --onto Q O
Reordering and editing commits usually creates untested
intermediate steps. You may want to check that your history
editing did not break anything by running a test, or at least
recompiling at intermediate points in history by using the "exec"
command (shortcut "x"). You may do so by creating a todo list
like this one:
pick deadbee Implement feature XXX
fixup f1a5c00 Fix to feature XXX
exec make
pick c0ffeee The oneline of the next commit
edit deadbab The oneline of the commit after
exec cd subdir; make test
...
The interactive rebase will stop when a command fails (i.e. exits
with non-0 status) to give you an opportunity to fix the problem.
You can continue with git rebase --continue.
The "exec" command launches the command in a shell (the default
one, usually /bin/sh), so you can use shell features (like "cd",
">", ";" ...). The command is run from the root of the working
tree.
$ git rebase -i --exec "make test"
This command lets you check that intermediate commits are
compilable. The todo list becomes like that:
pick 5928aea one
exec make test
pick 04d0fda two
exec make test
pick ba46169 three
exec make test
pick f4593f9 four
exec make test
In interactive mode, you can mark commits with the action "edit".
However, this does not necessarily mean that git rebase expects
the result of this edit to be exactly one commit. Indeed, you can
undo the commit, or you can add other commits. This can be used
to split a commit into two:
• Start an interactive rebase with git rebase -i <commit>^,
where <commit> is the commit you want to split. In fact, any
commit range will do, as long as it contains that commit.
• Mark the commit you want to split with the action "edit".
• When it comes to editing that commit, execute git reset
HEAD^. The effect is that the HEAD is rewound by one, and the
index follows suit. However, the working tree stays the same.
• Now add the changes to the index that you want to have in the
first commit. You can use git add (possibly interactively) or
git gui (or both) to do that.
• Commit the now-current index with whatever commit message is
appropriate now.
• Repeat the last two steps until your working tree is clean.
• Continue the rebase with git rebase --continue.
If you are not absolutely sure that the intermediate revisions
are consistent (they compile, pass the testsuite, etc.) you
should use git stash to stash away the not-yet-committed changes
after each commit, test, and amend the commit if fixes are
necessary.
Rebasing (or any other form of rewriting) a branch that others
have based work on is a bad idea: anyone downstream of it is
forced to manually fix their history. This section explains how
to do the fix from the downstream’s point of view. The real fix,
however, would be to avoid rebasing the upstream in the first
place.
To illustrate, suppose you are in a situation where someone
develops a subsystem branch, and you are working on a topic that
is dependent on this subsystem. You might end up with a history
like the following:
o---o---o---o---o---o---o---o master
\
o---o---o---o---o subsystem
\
*---*---* topic
If subsystem is rebased against master, the following happens:
o---o---o---o---o---o---o---o master
\ \
o---o---o---o---o o'--o'--o'--o'--o' subsystem
\
*---*---* topic
If you now continue development as usual, and eventually merge
topic to subsystem, the commits from subsystem will remain
duplicated forever:
o---o---o---o---o---o---o---o master
\ \
o---o---o---o---o o'--o'--o'--o'--o'--M subsystem
\ /
*---*---*-..........-*--* topic
Such duplicates are generally frowned upon because they clutter
up history, making it harder to follow. To clean things up, you
need to transplant the commits on topic to the new subsystem tip,
i.e., rebase topic. This becomes a ripple effect: anyone
downstream from topic is forced to rebase too, and so on!
There are two kinds of fixes, discussed in the following
subsections:
Easy case: The changes are literally the same.
This happens if the subsystem rebase was a simple rebase and
had no conflicts.
Hard case: The changes are not the same.
This happens if the subsystem rebase had conflicts, or used
--interactive to omit, edit, squash, or fixup commits; or if
the upstream used one of commit --amend, reset, or a full
history rewriting command like filter-repo[2].
The easy case
Only works if the changes (patch IDs based on the diff contents)
on subsystem are literally the same before and after the rebase
subsystem did.
In that case, the fix is easy because git rebase knows to skip
changes that are already present in the new upstream (unless
--reapply-cherry-picks is given). So if you say (assuming you’re
on topic)
$ git rebase subsystem
you will end up with the fixed history
o---o---o---o---o---o---o---o master
\
o'--o'--o'--o'--o' subsystem
\
*---*---* topic
The hard case
Things get more complicated if the subsystem changes do not
exactly correspond to the ones before the rebase.
Note
While an "easy case recovery" sometimes appears to be
successful even in the hard case, it may have unintended
consequences. For example, a commit that was removed via git
rebase --interactive will be resurrected!
The idea is to manually tell git rebase "where the old subsystem
ended and your topic began", that is, what the old merge base
between them was. You will have to find a way to name the last
commit of the old subsystem, for example:
• With the subsystem reflog: after git fetch, the old tip of
subsystem is at subsystem@{1}. Subsequent fetches will
increase the number. (See git-reflog(1).)
• Relative to the tip of topic: knowing that your topic has
three commits, the old tip of subsystem must be topic~3.
You can then transplant the old subsystem..topic to the new tip
by saying (for the reflog case, and assuming you are on topic
already):
$ git rebase --onto subsystem subsystem@{1}
The ripple effect of a "hard case" recovery is especially bad:
everyone downstream from topic will now have to perform a "hard
case" recovery too!
The interactive rebase command was originally designed to handle
individual patch series. As such, it makes sense to exclude merge
commits from the todo list, as the developer may have merged the
then-current master while working on the branch, only to rebase
all the commits onto master eventually (skipping the merge
commits).
However, there are legitimate reasons why a developer may want to
recreate merge commits: to keep the branch structure (or "commit
topology") when working on multiple, inter-related branches.
In the following example, the developer works on a topic branch
that refactors the way buttons are defined, and on another topic
branch that uses that refactoring to implement a "Report a bug"
button. The output of git log --graph --format=%s -5 may look
like this:
* Merge branch 'report-a-bug'
|\
| * Add the feedback button
* | Merge branch 'refactor-button'
|\ \
| |/
| * Use the Button class for all buttons
| * Extract a generic Button class from the DownloadButton one
The developer might want to rebase those commits to a newer
master while keeping the branch topology, for example when the
first topic branch is expected to be integrated into master much
earlier than the second one, say, to resolve merge conflicts with
changes to the DownloadButton class that made it into master.
This rebase can be performed using the --rebase-merges option. It
will generate a todo list looking like this:
label onto
# Branch: refactor-button
reset onto
pick 123456 Extract a generic Button class from the DownloadButton one
pick 654321 Use the Button class for all buttons
label refactor-button
# Branch: report-a-bug
reset refactor-button # Use the Button class for all buttons
pick abcdef Add the feedback button
label report-a-bug
reset onto
merge -C a1b2c3 refactor-button # Merge 'refactor-button'
merge -C 6f5e4d report-a-bug # Merge 'report-a-bug'
In contrast to a regular interactive rebase, there are label,
reset and merge commands in addition to pick ones.
The label command associates a label with the current HEAD when
that command is executed. These labels are created as
worktree-local refs (refs/rewritten/<label>) that will be deleted
when the rebase finishes. That way, rebase operations in multiple
worktrees linked to the same repository do not interfere with one
another. If the label command fails, it is rescheduled
immediately, with a helpful message how to proceed.
The reset command resets the HEAD, index and worktree to the
specified revision. It is similar to an exec git reset --hard
<label>, but refuses to overwrite untracked files. If the reset
command fails, it is rescheduled immediately, with a helpful
message how to edit the todo list (this typically happens when a
reset command was inserted into the todo list manually and
contains a typo).
The merge command will merge the specified revision(s) into
whatever is HEAD at that time. With -C <original-commit>, the
commit message of the specified merge commit will be used. When
the -C is changed to a lower-case -c, the message will be opened
in an editor after a successful merge so that the user can edit
the message.
If a merge command fails for any reason other than merge
conflicts (i.e. when the merge operation did not even start), it
is rescheduled immediately.
By default, the merge command will use the ort merge strategy for
regular merges, and octopus for octopus merges. One can specify a
default strategy for all merges using the --strategy argument
when invoking rebase, or can override specific merges in the
interactive list of commands by using an exec command to call git
merge explicitly with a --strategy argument. Note that when
calling git merge explicitly like this, you can make use of the
fact that the labels are worktree-local refs (the ref
refs/rewritten/onto would correspond to the label onto, for
example) in order to refer to the branches you want to merge.
Note: the first command (label onto) labels the revision onto
which the commits are rebased; The name onto is just a
convention, as a nod to the --onto option.
It is also possible to introduce completely new merge commits
from scratch by adding a command of the form merge <merge-head>.
This form will generate a tentative commit message and always
open an editor to let the user edit it. This can be useful e.g.
when a topic branch turns out to address more than a single
concern and wants to be split into two or even more topic
branches. Consider this todo list:
pick 192837 Switch from GNU Makefiles to CMake
pick 5a6c7e Document the switch to CMake
pick 918273 Fix detection of OpenSSL in CMake
pick afbecd http: add support for TLS v1.3
pick fdbaec Fix detection of cURL in CMake on Windows
The one commit in this list that is not related to CMake may very
well have been motivated by working on fixing all those bugs
introduced by switching to CMake, but it addresses a different
concern. To split this branch into two topic branches, the todo
list could be edited like this:
label onto
pick afbecd http: add support for TLS v1.3
label tlsv1.3
reset onto
pick 192837 Switch from GNU Makefiles to CMake
pick 918273 Fix detection of OpenSSL in CMake
pick fdbaec Fix detection of cURL in CMake on Windows
pick 5a6c7e Document the switch to CMake
label cmake
reset onto
merge tlsv1.3
merge cmake
Everything below this line in this section is selectively
included from the git-config(1) documentation. The content is the
same as what’s found there:
rebase.backend
Default backend to use for rebasing. Possible choices are
apply or merge. In the future, if the merge backend gains all
remaining capabilities of the apply backend, this setting may
become unused.
rebase.stat
Whether to show a diffstat of what changed upstream since the
last rebase. False by default.
rebase.autoSquash
If set to true, enable the --autosquash option of
git-rebase(1) by default for interactive mode. This can be
overridden with the --no-autosquash option.
rebase.autoStash
When set to true, automatically create a temporary stash
entry before the operation begins, and apply it after the
operation ends. This means that you can run rebase on a dirty
worktree. However, use with care: the final stash application
after a successful rebase might result in non-trivial
conflicts. This option can be overridden by the
--no-autostash and --autostash options of git-rebase(1).
Defaults to false.
rebase.updateRefs
If set to true enable --update-refs option by default.
rebase.missingCommitsCheck
If set to "warn", git rebase -i will print a warning if some
commits are removed (e.g. a line was deleted), however the
rebase will still proceed. If set to "error", it will print
the previous warning and stop the rebase, git rebase
--edit-todo can then be used to correct the error. If set to
"ignore", no checking is done. To drop a commit without
warning or error, use the drop command in the todo list.
Defaults to "ignore".
rebase.instructionFormat
A format string, as specified in git-log(1), to be used for
the todo list during an interactive rebase. The format will
automatically have the commit hash prepended to the format.
rebase.abbreviateCommands
If set to true, git rebase will use abbreviated command names
in the todo list resulting in something like this:
p deadbee The oneline of the commit
p fa1afe1 The oneline of the next commit
...
instead of:
pick deadbee The oneline of the commit
pick fa1afe1 The oneline of the next commit
...
Defaults to false.
rebase.rescheduleFailedExec
Automatically reschedule exec commands that failed. This only
makes sense in interactive mode (or when an --exec option was
provided). This is the same as specifying the
--reschedule-failed-exec option.
rebase.forkPoint
If set to false set --no-fork-point option by default.
rebase.rebaseMerges
Whether and how to set the --rebase-merges option by default.
Can be rebase-cousins, no-rebase-cousins, or a boolean.
Setting to true or to no-rebase-cousins is equivalent to
--rebase-merges=no-rebase-cousins, setting to rebase-cousins
is equivalent to --rebase-merges=rebase-cousins, and setting
to false is equivalent to --no-rebase-merges. Passing
--rebase-merges on the command line, with or without an
argument, overrides any rebase.rebaseMerges configuration.
rebase.maxLabelLength
When generating label names from commit subjects, truncate
the names to this length. By default, the names are truncated
to a little less than NAME_MAX (to allow e.g. .lock files to
be written for the corresponding loose refs).
sequence.editor
Text editor used by git rebase -i for editing the rebase
instruction file. The value is meant to be interpreted by the
shell when it is used. It can be overridden by the
GIT_SEQUENCE_EDITOR environment variable. When not
configured, the default commit message editor is used
instead.
Part of the git(1) suite
1. revert-a-faulty-merge How-To
file:///home/mtk/share/doc/git-doc/howto/revert-a-faulty-merge.html
2. filter-repo
https://github.com/newren/git-filter-repo
This page is part of the git (Git distributed version control
system) project. Information about the project can be found at
⟨http://git-scm.com/⟩. If you have a bug report for this manual
page, see ⟨http://git-scm.com/community⟩. This page was obtained
from the project's upstream Git repository
⟨https://github.com/git/git.git⟩ on 2024-06-14. (At that time,
the date of the most recent commit that was found in the
repository was 2024-06-12.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
Git 2.45.2.492.gd63586 2024-06-12 GIT-REBASE(1)
Pages that refer to this page: git(1), git-branch(1), git-cherry(1), git-commit(1), git-config(1), git-filter-branch(1), git-format-patch(1), git-pull(1), git-rebase(1), git-replace(1), git-reset(1), git-submodule(1), git-svn(1), stg-repair(1), githooks(5), giteveryday(7), gitfaq(7), gitworkflows(7)
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