1GIT-MERGE(1) Git Manual GIT-MERGE(1)
2
6 git-merge - Join two or more development histories together
7
9 git merge [-n] [--stat] [--no-commit] [--squash] [--[no-]edit]
10 [-s <strategy>] [-X <strategy-option>] [-S[<keyid>]]
11 [--[no-]allow-unrelated-histories]
12 [--[no-]rerere-autoupdate] [-m <msg>] [-F <file>] [<commit>...]
13 git merge --abort
14 git merge --continue
15
18 Incorporates changes from the named commits (since the time their
19 histories diverged from the current branch) into the current branch.
20 This command is used by git pull to incorporate changes from another
21 repository and can be used by hand to merge changes from one branch
22 into another.
23 Assume the following history exists and the current branch is "master":
25 A---B---C topic
27 /
28 D---E---F---G master
29 Then "git merge topic" will replay the changes made on the topic branch
32 since it diverged from master (i.e., E) until its current commit (C) on
33 top of master, and record the result in a new commit along with the
34 names of the two parent commits and a log message from the user
35 describing the changes.
36 A---B---C topic
38 / \
39 D---E---F---G---H master
40 The second syntax ("git merge --abort") can only be run after the merge
43 has resulted in conflicts. git merge --abort will abort the merge
44 process and try to reconstruct the pre-merge state. However, if there
45 were uncommitted changes when the merge started (and especially if
46 those changes were further modified after the merge was started), git
47 merge --abort will in some cases be unable to reconstruct the original
48 (pre-merge) changes. Therefore:
49 Warning: Running git merge with non-trivial uncommitted changes is
51 discouraged: while possible, it may leave you in a state that is hard
52 to back out of in the case of a conflict.
53 The third syntax ("git merge --continue") can only be run after the
55 merge has resulted in conflicts.
56
58 --commit, --no-commit
59 Perform the merge and commit the result. This option can be used to
60 override --no-commit.
61 With --no-commit perform the merge but pretend the merge failed and
63 do not autocommit, to give the user a chance to inspect and further
64 tweak the merge result before committing.
65 --edit, -e, --no-edit
67 Invoke an editor before committing successful mechanical merge to
68 further edit the auto-generated merge message, so that the user can
69 explain and justify the merge. The --no-edit option can be used to
70 accept the auto-generated message (this is generally discouraged).
71 The --edit (or -e) option is still useful if you are giving a draft
72 message with the -m option from the command line and want to edit
73 it in the editor.
74 Older scripts may depend on the historical behaviour of not
76 allowing the user to edit the merge log message. They will see an
77 editor opened when they run git merge. To make it easier to adjust
78 such scripts to the updated behaviour, the environment variable
79 GIT_MERGE_AUTOEDIT can be set to no at the beginning of them.
80 --ff
82 When the merge resolves as a fast-forward, only update the branch
83 pointer, without creating a merge commit. This is the default
84 behavior.
85 --no-ff
87 Create a merge commit even when the merge resolves as a
88 fast-forward. This is the default behaviour when merging an
89 annotated (and possibly signed) tag that is not stored in its
90 natural place in refs/tags/ hierarchy.
91 --ff-only
93 Refuse to merge and exit with a non-zero status unless the current
94 HEAD is already up to date or the merge can be resolved as a
95 fast-forward.
96 -S[<keyid>], --gpg-sign[=<keyid>]
98 GPG-sign the resulting merge commit. The keyid argument is optional
99 and defaults to the committer identity; if specified, it must be
100 stuck to the option without a space.
101 --log[=<n>], --no-log
103 In addition to branch names, populate the log message with one-line
104 descriptions from at most <n> actual commits that are being merged.
105 See also git-fmt-merge-msg(1).
106 With --no-log do not list one-line descriptions from the actual
108 commits being merged.
109 --signoff, --no-signoff
111 Add Signed-off-by line by the committer at the end of the commit
112 log message. The meaning of a signoff depends on the project, but
113 it typically certifies that committer has the rights to submit this
114 work under the same license and agrees to a Developer Certificate
115 of Origin (see http://developercertificate.org/ for more
116 information).
117 With --no-signoff do not add a Signed-off-by line.
119 --stat, -n, --no-stat
121 Show a diffstat at the end of the merge. The diffstat is also
122 controlled by the configuration option merge.stat.
123 With -n or --no-stat do not show a diffstat at the end of the
125 merge.
126 --squash, --no-squash
128 Produce the working tree and index state as if a real merge
129 happened (except for the merge information), but do not actually
130 make a commit, move the HEAD, or record $GIT_DIR/MERGE_HEAD (to
131 cause the next git commit command to create a merge commit). This
132 allows you to create a single commit on top of the current branch
133 whose effect is the same as merging another branch (or more in case
134 of an octopus).
135 With --no-squash perform the merge and commit the result. This
137 option can be used to override --squash.
138 -s <strategy>, --strategy=<strategy>
140 Use the given merge strategy; can be supplied more than once to
141 specify them in the order they should be tried. If there is no -s
142 option, a built-in list of strategies is used instead (git
143 merge-recursive when merging a single head, git merge-octopus
144 otherwise).
145 -X <option>, --strategy-option=<option>
147 Pass merge strategy specific option through to the merge strategy.
148 --verify-signatures, --no-verify-signatures
150 Verify that the tip commit of the side branch being merged is
151 signed with a valid key, i.e. a key that has a valid uid: in the
152 default trust model, this means the signing key has been signed by
153 a trusted key. If the tip commit of the side branch is not signed
154 with a valid key, the merge is aborted.
155 --summary, --no-summary
157 Synonyms to --stat and --no-stat; these are deprecated and will be
158 removed in the future.
159 -q, --quiet
161 Operate quietly. Implies --no-progress.
162 -v, --verbose
164 Be verbose.
165 --progress, --no-progress
167 Turn progress on/off explicitly. If neither is specified, progress
168 is shown if standard error is connected to a terminal. Note that
169 not all merge strategies may support progress reporting.
170 --allow-unrelated-histories
172 By default, git merge command refuses to merge histories that do
173 not share a common ancestor. This option can be used to override
174 this safety when merging histories of two projects that started
175 their lives independently. As that is a very rare occasion, no
176 configuration variable to enable this by default exists and will
177 not be added.
178 -m <msg>
180 Set the commit message to be used for the merge commit (in case one
181 is created).
182 If --log is specified, a shortlog of the commits being merged will
184 be appended to the specified message.
185 The git fmt-merge-msg command can be used to give a good default
187 for automated git merge invocations. The automated message can
188 include the branch description.
189 -F <file>, --file=<file>
191 Read the commit message to be used for the merge commit (in case
192 one is created).
193 If --log is specified, a shortlog of the commits being merged will
195 be appended to the specified message.
196 --[no-]rerere-autoupdate
198 Allow the rerere mechanism to update the index with the result of
199 auto-conflict resolution if possible.
200 --abort
202 Abort the current conflict resolution process, and try to
203 reconstruct the pre-merge state.
204 If there were uncommitted worktree changes present when the merge
206 started, git merge --abort will in some cases be unable to
207 reconstruct these changes. It is therefore recommended to always
208 commit or stash your changes before running git merge.
209 git merge --abort is equivalent to git reset --merge when
211 MERGE_HEAD is present.
212 --continue
214 After a git merge stops due to conflicts you can conclude the merge
215 by running git merge --continue (see "HOW TO RESOLVE CONFLICTS"
216 section below).
217 <commit>...
219 Commits, usually other branch heads, to merge into our branch.
220 Specifying more than one commit will create a merge with more than
221 two parents (affectionately called an Octopus merge).
222 If no commit is given from the command line, merge the
224 remote-tracking branches that the current branch is configured to
225 use as its upstream. See also the configuration section of this
226 manual page.
227 When FETCH_HEAD (and no other commit) is specified, the branches
229 recorded in the .git/FETCH_HEAD file by the previous invocation of
230 git fetch for merging are merged to the current branch.
231
233 Before applying outside changes, you should get your own work in good
234 shape and committed locally, so it will not be clobbered if there are
235 conflicts. See also git-stash(1). git pull and git merge will stop
236 without doing anything when local uncommitted changes overlap with
237 files that git pull/git merge may need to update.
238 To avoid recording unrelated changes in the merge commit, git pull and
240 git merge will also abort if there are any changes registered in the
241 index relative to the HEAD commit. (Special narrow exceptions to this
242 rule may exist depending on which merge strategy is in use, but
243 generally, the index must match HEAD.)
244 If all named commits are already ancestors of HEAD, git merge will exit
246 early with the message "Already up to date."
247
249 Often the current branch head is an ancestor of the named commit. This
250 is the most common case especially when invoked from git pull: you are
251 tracking an upstream repository, you have committed no local changes,
252 and now you want to update to a newer upstream revision. In this case,
253 a new commit is not needed to store the combined history; instead, the
254 HEAD (along with the index) is updated to point at the named commit,
255 without creating an extra merge commit.
256 This behavior can be suppressed with the --no-ff option.
258
260 Except in a fast-forward merge (see above), the branches to be merged
261 must be tied together by a merge commit that has both of them as its
262 parents.
263 A merged version reconciling the changes from all branches to be merged
265 is committed, and your HEAD, index, and working tree are updated to it.
266 It is possible to have modifications in the working tree as long as
267 they do not overlap; the update will preserve them.
268 When it is not obvious how to reconcile the changes, the following
270 happens:
271 1. The HEAD pointer stays the same.
273 2. The MERGE_HEAD ref is set to point to the other branch head.
275 3. Paths that merged cleanly are updated both in the index file and in
277 your working tree.
278 4. For conflicting paths, the index file records up to three versions:
280 stage 1 stores the version from the common ancestor, stage 2 from
281 HEAD, and stage 3 from MERGE_HEAD (you can inspect the stages with
282 git ls-files -u). The working tree files contain the result of the
283 "merge" program; i.e. 3-way merge results with familiar conflict
284 markers <<< === >>>.
285 5. No other changes are made. In particular, the local modifications
287 you had before you started merge will stay the same and the index
288 entries for them stay as they were, i.e. matching HEAD.
289 If you tried a merge which resulted in complex conflicts and want to
291 start over, you can recover with git merge --abort.
292
294 When merging an annotated (and possibly signed) tag, Git always creates
295 a merge commit even if a fast-forward merge is possible, and the commit
296 message template is prepared with the tag message. Additionally, if the
297 tag is signed, the signature check is reported as a comment in the
298 message template. See also git-tag(1).
299 When you want to just integrate with the work leading to the commit
301 that happens to be tagged, e.g. synchronizing with an upstream release
302 point, you may not want to make an unnecessary merge commit.
303 In such a case, you can "unwrap" the tag yourself before feeding it to
305 git merge, or pass --ff-only when you do not have any work on your own.
306 e.g.
307 git fetch origin
309 git merge v1.2.3^0
310 git merge --ff-only v1.2.3
311
314 During a merge, the working tree files are updated to reflect the
315 result of the merge. Among the changes made to the common ancestor’s
316 version, non-overlapping ones (that is, you changed an area of the file
317 while the other side left that area intact, or vice versa) are
318 incorporated in the final result verbatim. When both sides made changes
319 to the same area, however, Git cannot randomly pick one side over the
320 other, and asks you to resolve it by leaving what both sides did to
321 that area.
322 By default, Git uses the same style as the one used by the "merge"
324 program from the RCS suite to present such a conflicted hunk, like
325 this:
326 Here are lines that are either unchanged from the common
328 ancestor, or cleanly resolved because only one side changed.
329 <<<<<<< yours:sample.txt
330 Conflict resolution is hard;
331 let's go shopping.
332 =======
333 Git makes conflict resolution easy.
334 >>>>>>> theirs:sample.txt
335 And here is another line that is cleanly resolved or unmodified.
336 The area where a pair of conflicting changes happened is marked with
339 markers <<<<<<<, =======, and >>>>>>>. The part before the ======= is
340 typically your side, and the part afterwards is typically their side.
341 The default format does not show what the original said in the
343 conflicting area. You cannot tell how many lines are deleted and
344 replaced with Barbie’s remark on your side. The only thing you can tell
345 is that your side wants to say it is hard and you’d prefer to go
346 shopping, while the other side wants to claim it is easy.
347 An alternative style can be used by setting the "merge.conflictStyle"
349 configuration variable to "diff3". In "diff3" style, the above conflict
350 may look like this:
351 Here are lines that are either unchanged from the common
353 ancestor, or cleanly resolved because only one side changed.
354 <<<<<<< yours:sample.txt
355 Conflict resolution is hard;
356 let's go shopping.
357 |||||||
358 Conflict resolution is hard.
359 =======
360 Git makes conflict resolution easy.
361 >>>>>>> theirs:sample.txt
362 And here is another line that is cleanly resolved or unmodified.
363 In addition to the <<<<<<<, =======, and >>>>>>> markers, it uses
366 another ||||||| marker that is followed by the original text. You can
367 tell that the original just stated a fact, and your side simply gave in
368 to that statement and gave up, while the other side tried to have a
369 more positive attitude. You can sometimes come up with a better
370 resolution by viewing the original.
371
373 After seeing a conflict, you can do two things:
374 · Decide not to merge. The only clean-ups you need are to reset the
376 index file to the HEAD commit to reverse 2. and to clean up working
377 tree changes made by 2. and 3.; git merge --abort can be used for
378 this.
379 · Resolve the conflicts. Git will mark the conflicts in the working
381 tree. Edit the files into shape and git add them to the index. Use
382 git commit or git merge --continue to seal the deal. The latter
383 command checks whether there is a (interrupted) merge in progress
384 before calling git commit.
385 You can work through the conflict with a number of tools:
387 · Use a mergetool. git mergetool to launch a graphical mergetool
389 which will work you through the merge.
390 · Look at the diffs. git diff will show a three-way diff,
392 highlighting changes from both the HEAD and MERGE_HEAD versions.
393 · Look at the diffs from each branch. git log --merge -p <path> will
395 show diffs first for the HEAD version and then the MERGE_HEAD
396 version.
397 · Look at the originals. git show :1:filename shows the common
399 ancestor, git show :2:filename shows the HEAD version, and git show
400 :3:filename shows the MERGE_HEAD version.
401
403 · Merge branches fixes and enhancements on top of the current branch,
404 making an octopus merge:
405 $ git merge fixes enhancements
407 · Merge branch obsolete into the current branch, using ours merge
410 strategy:
411 $ git merge -s ours obsolete
413 · Merge branch maint into the current branch, but do not make a new
416 commit automatically:
417 $ git merge --no-commit maint
419 This can be used when you want to include further changes to the
421 merge, or want to write your own merge commit message.
422 You should refrain from abusing this option to sneak substantial
424 changes into a merge commit. Small fixups like bumping
425 release/version name would be acceptable.
426
428 The merge mechanism (git merge and git pull commands) allows the
429 backend merge strategies to be chosen with -s option. Some strategies
430 can also take their own options, which can be passed by giving
431 -X<option> arguments to git merge and/or git pull.
432 resolve
434 This can only resolve two heads (i.e. the current branch and
435 another branch you pulled from) using a 3-way merge algorithm. It
436 tries to carefully detect criss-cross merge ambiguities and is
437 considered generally safe and fast.
438 recursive
440 This can only resolve two heads using a 3-way merge algorithm. When
441 there is more than one common ancestor that can be used for 3-way
442 merge, it creates a merged tree of the common ancestors and uses
443 that as the reference tree for the 3-way merge. This has been
444 reported to result in fewer merge conflicts without causing
445 mismerges by tests done on actual merge commits taken from Linux
446 2.6 kernel development history. Additionally this can detect and
447 handle merges involving renames, but currently cannot make use of
448 detected copies. This is the default merge strategy when pulling or
449 merging one branch.
450 The recursive strategy can take the following options:
452 ours
454 This option forces conflicting hunks to be auto-resolved
455 cleanly by favoring our version. Changes from the other tree
456 that do not conflict with our side are reflected to the merge
457 result. For a binary file, the entire contents are taken from
458 our side.
459 This should not be confused with the ours merge strategy, which
461 does not even look at what the other tree contains at all. It
462 discards everything the other tree did, declaring our history
463 contains all that happened in it.
464 theirs
466 This is the opposite of ours; note that, unlike ours, there is
467 no theirs merge strategy to confuse this merge option with.
468 patience
470 With this option, merge-recursive spends a little extra time to
471 avoid mismerges that sometimes occur due to unimportant
472 matching lines (e.g., braces from distinct functions). Use this
473 when the branches to be merged have diverged wildly. See also
474 git-diff(1) --patience.
475 diff-algorithm=[patience|minimal|histogram|myers]
477 Tells merge-recursive to use a different diff algorithm, which
478 can help avoid mismerges that occur due to unimportant matching
479 lines (such as braces from distinct functions). See also git-
480 diff(1) --diff-algorithm.
481 ignore-space-change, ignore-all-space, ignore-space-at-eol,
483 ignore-cr-at-eol
484 Treats lines with the indicated type of whitespace change as
485 unchanged for the sake of a three-way merge. Whitespace changes
486 mixed with other changes to a line are not ignored. See also
487 git-diff(1) -b, -w, --ignore-space-at-eol, and
488 --ignore-cr-at-eol.
489 · If their version only introduces whitespace changes to a
491 line, our version is used;
492 · If our version introduces whitespace changes but their
494 version includes a substantial change, their version is
495 used;
496 · Otherwise, the merge proceeds in the usual way.
498 renormalize
500 This runs a virtual check-out and check-in of all three stages
501 of a file when resolving a three-way merge. This option is
502 meant to be used when merging branches with different clean
503 filters or end-of-line normalization rules. See "Merging
504 branches with differing checkin/checkout attributes" in
505 gitattributes(5) for details.
506 no-renormalize
508 Disables the renormalize option. This overrides the
509 merge.renormalize configuration variable.
510 no-renames
512 Turn off rename detection. This overrides the merge.renames
513 configuration variable. See also git-diff(1) --no-renames.
514 find-renames[=<n>]
516 Turn on rename detection, optionally setting the similarity
517 threshold. This is the default. This overrides the
518 merge.renames configuration variable. See also git-diff(1)
519 --find-renames.
520 rename-threshold=<n>
522 Deprecated synonym for find-renames=<n>.
523 subtree[=<path>]
525 This option is a more advanced form of subtree strategy, where
526 the strategy makes a guess on how two trees must be shifted to
527 match with each other when merging. Instead, the specified path
528 is prefixed (or stripped from the beginning) to make the shape
529 of two trees to match.
530 octopus
532 This resolves cases with more than two heads, but refuses to do a
533 complex merge that needs manual resolution. It is primarily meant
534 to be used for bundling topic branch heads together. This is the
535 default merge strategy when pulling or merging more than one
536 branch.
537 ours
539 This resolves any number of heads, but the resulting tree of the
540 merge is always that of the current branch head, effectively
541 ignoring all changes from all other branches. It is meant to be
542 used to supersede old development history of side branches. Note
543 that this is different from the -Xours option to the recursive
544 merge strategy.
545 subtree
547 This is a modified recursive strategy. When merging trees A and B,
548 if B corresponds to a subtree of A, B is first adjusted to match
549 the tree structure of A, instead of reading the trees at the same
550 level. This adjustment is also done to the common ancestor tree.
551 With the strategies that use 3-way merge (including the default,
553 recursive), if a change is made on both branches, but later reverted on
554 one of the branches, that change will be present in the merged result;
555 some people find this behavior confusing. It occurs because only the
556 heads and the merge base are considered when performing a merge, not
557 the individual commits. The merge algorithm therefore considers the
558 reverted change as no change at all, and substitutes the changed
559 version instead.
560
562 merge.conflictStyle
563 Specify the style in which conflicted hunks are written out to
564 working tree files upon merge. The default is "merge", which shows
565 a <<<<<<< conflict marker, changes made by one side, a =======
566 marker, changes made by the other side, and then a >>>>>>> marker.
567 An alternate style, "diff3", adds a ||||||| marker and the original
568 text before the ======= marker.
569 merge.defaultToUpstream
571 If merge is called without any commit argument, merge the upstream
572 branches configured for the current branch by using their last
573 observed values stored in their remote-tracking branches. The
574 values of the branch.<current branch>.merge that name the branches
575 at the remote named by branch.<current branch>.remote are
576 consulted, and then they are mapped via remote.<remote>.fetch to
577 their corresponding remote-tracking branches, and the tips of these
578 tracking branches are merged.
579 merge.ff
581 By default, Git does not create an extra merge commit when merging
582 a commit that is a descendant of the current commit. Instead, the
583 tip of the current branch is fast-forwarded. When set to false,
584 this variable tells Git to create an extra merge commit in such a
585 case (equivalent to giving the --no-ff option from the command
586 line). When set to only, only such fast-forward merges are allowed
587 (equivalent to giving the --ff-only option from the command line).
588 merge.verifySignatures
590 If true, this is equivalent to the --verify-signatures command line
591 option. See git-merge(1) for details.
592 merge.branchdesc
594 In addition to branch names, populate the log message with the
595 branch description text associated with them. Defaults to false.
596 merge.log
598 In addition to branch names, populate the log message with at most
599 the specified number of one-line descriptions from the actual
600 commits that are being merged. Defaults to false, and true is a
601 synonym for 20.
602 merge.renameLimit
604 The number of files to consider when performing rename detection
605 during a merge; if not specified, defaults to the value of
606 diff.renameLimit. This setting has no effect if rename detection is
607 turned off.
608 merge.renames
610 Whether and how Git detects renames. If set to "false", rename
611 detection is disabled. If set to "true", basic rename detection is
612 enabled. Defaults to the value of diff.renames.
613 merge.renormalize
615 Tell Git that canonical representation of files in the repository
616 has changed over time (e.g. earlier commits record text files with
617 CRLF line endings, but recent ones use LF line endings). In such a
618 repository, Git can convert the data recorded in commits to a
619 canonical form before performing a merge to reduce unnecessary
620 conflicts. For more information, see section "Merging branches with
621 differing checkin/checkout attributes" in gitattributes(5).
622 merge.stat
624 Whether to print the diffstat between ORIG_HEAD and the merge
625 result at the end of the merge. True by default.
626 merge.tool
628 Controls which merge tool is used by git-mergetool(1). The list
629 below shows the valid built-in values. Any other value is treated
630 as a custom merge tool and requires that a corresponding
631 mergetool.<tool>.cmd variable is defined.
632 merge.guitool
634 Controls which merge tool is used by git-mergetool(1) when the
635 -g/--gui flag is specified. The list below shows the valid built-in
636 values. Any other value is treated as a custom merge tool and
637 requires that a corresponding mergetool.<guitool>.cmd variable is
638 defined.
639 · araxis
641 · bc
643 · bc3
645 · codecompare
647 · deltawalker
649 · diffmerge
651 · diffuse
653 · ecmerge
655 · emerge
657 · examdiff
659 · guiffy
661 · gvimdiff
663 · gvimdiff2
665 · gvimdiff3
667 · kdiff3
669 · meld
671 · opendiff
673 · p4merge
675 · tkdiff
677 · tortoisemerge
679 · vimdiff
681 · vimdiff2
683 · vimdiff3
685 · winmerge
687 · xxdiff
689 merge.verbosity
691 Controls the amount of output shown by the recursive merge
692 strategy. Level 0 outputs nothing except a final error message if
693 conflicts were detected. Level 1 outputs only conflicts, 2 outputs
694 conflicts and file changes. Level 5 and above outputs debugging
695 information. The default is level 2. Can be overridden by the
696 GIT_MERGE_VERBOSITY environment variable.
697 merge.<driver>.name
699 Defines a human-readable name for a custom low-level merge driver.
700 See gitattributes(5) for details.
701 merge.<driver>.driver
703 Defines the command that implements a custom low-level merge
704 driver. See gitattributes(5) for details.
705 merge.<driver>.recursive
707 Names a low-level merge driver to be used when performing an
708 internal merge between common ancestors. See gitattributes(5) for
709 details.
710 branch.<name>.mergeOptions
712 Sets default options for merging into branch <name>. The syntax and
713 supported options are the same as those of git merge, but option
714 values containing whitespace characters are currently not
715 supported.
716
718 git-fmt-merge-msg(1), git-pull(1), gitattributes(5), git-reset(1), git-
719 diff(1), git-ls-files(1), git-add(1), git-rm(1), git-mergetool(1)
720
722 Part of the git(1) suite
723Git 2.20.1 12/15/2018 GIT-MERGE(1)