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+git-merge(1)
+============
+
+NAME
+----
+git-merge - Join two or more development histories together
+
+
+SYNOPSIS
+--------
+[verse]
+'git merge' [-n] [--stat] [--no-commit] [--squash] [--[no-]edit]
+ [-s <strategy>] [-X <strategy-option>] [-S[<key-id>]]
+ [--[no-]rerere-autoupdate] [-m <msg>] [<commit>...]
+'git merge' <msg> HEAD <commit>...
+'git merge' --abort
+
+DESCRIPTION
+-----------
+Incorporates changes from the named commits (since the time their
+histories diverged from the current branch) into the current
+branch. This command is used by 'git pull' to incorporate changes
+from another repository and can be used by hand to merge changes
+from one branch into another.
+
+Assume the following history exists and the current branch is
+"`master`":
+
+------------
+ A---B---C topic
+ /
+ D---E---F---G master
+------------
+
+Then "`git merge topic`" will replay the changes made on the
+`topic` branch since it diverged from `master` (i.e., `E`) until
+its current commit (`C`) on top of `master`, and record the result
+in a new commit along with the names of the two parent commits and
+a log message from the user describing the changes.
+
+------------
+ A---B---C topic
+ / \
+ D---E---F---G---H master
+------------
+
+The second syntax (<msg> `HEAD` <commit>...) is supported for
+historical reasons. Do not use it from the command line or in
+new scripts. It is the same as `git merge -m <msg> <commit>...`.
+
+The third syntax ("`git merge --abort`") can only be run after the
+merge has resulted in conflicts. 'git merge --abort' will abort the
+merge process and try to reconstruct the pre-merge state. However,
+if there were uncommitted changes when the merge started (and
+especially if those changes were further modified after the merge
+was started), 'git merge --abort' will in some cases be unable to
+reconstruct the original (pre-merge) changes. Therefore:
+
+*Warning*: Running 'git merge' with non-trivial uncommitted changes is
+discouraged: while possible, it may leave you in a state that is hard to
+back out of in the case of a conflict.
+
+
+OPTIONS
+-------
+include::merge-options.txt[]
+
+-S[<keyid>]::
+--gpg-sign[=<keyid>]::
+ GPG-sign the resulting merge commit.
+
+-m <msg>::
+ Set the commit message to be used for the merge commit (in
+ case one is created).
++
+If `--log` is specified, a shortlog of the commits being merged
+will be appended to the specified message.
++
+The 'git fmt-merge-msg' command can be
+used to give a good default for automated 'git merge'
+invocations.
+
+--[no-]rerere-autoupdate::
+ Allow the rerere mechanism to update the index with the
+ result of auto-conflict resolution if possible.
+
+--abort::
+ Abort the current conflict resolution process, and
+ try to reconstruct the pre-merge state.
++
+If there were uncommitted worktree changes present when the merge
+started, 'git merge --abort' will in some cases be unable to
+reconstruct these changes. It is therefore recommended to always
+commit or stash your changes before running 'git merge'.
++
+'git merge --abort' is equivalent to 'git reset --merge' when
+`MERGE_HEAD` is present.
+
+<commit>...::
+ Commits, usually other branch heads, to merge into our branch.
+ Specifying more than one commit will create a merge with
+ more than two parents (affectionately called an Octopus merge).
++
+If no commit is given from the command line, and if `merge.defaultToUpstream`
+configuration variable is set, merge the remote-tracking branches
+that the current branch is configured to use as its upstream.
+See also the configuration section of this manual page.
+
+
+PRE-MERGE CHECKS
+----------------
+
+Before applying outside changes, you should get your own work in
+good shape and committed locally, so it will not be clobbered if
+there are conflicts. See also linkgit:git-stash[1].
+'git pull' and 'git merge' will stop without doing anything when
+local uncommitted changes overlap with files that 'git pull'/'git
+merge' may need to update.
+
+To avoid recording unrelated changes in the merge commit,
+'git pull' and 'git merge' will also abort if there are any changes
+registered in the index relative to the `HEAD` commit. (One
+exception is when the changed index entries are in the state that
+would result from the merge already.)
+
+If all named commits are already ancestors of `HEAD`, 'git merge'
+will exit early with the message "Already up-to-date."
+
+FAST-FORWARD MERGE
+------------------
+
+Often the current branch head is an ancestor of the named commit.
+This is the most common case especially when invoked from 'git
+pull': you are tracking an upstream repository, you have committed
+no local changes, and now you want to update to a newer upstream
+revision. In this case, a new commit is not needed to store the
+combined history; instead, the `HEAD` (along with the index) is
+updated to point at the named commit, without creating an extra
+merge commit.
+
+This behavior can be suppressed with the `--no-ff` option.
+
+TRUE MERGE
+----------
+
+Except in a fast-forward merge (see above), the branches to be
+merged must be tied together by a merge commit that has both of them
+as its parents.
+
+A merged version reconciling the changes from all branches to be
+merged is committed, and your `HEAD`, index, and working tree are
+updated to it. It is possible to have modifications in the working
+tree as long as they do not overlap; the update will preserve them.
+
+When it is not obvious how to reconcile the changes, the following
+happens:
+
+1. The `HEAD` pointer stays the same.
+2. The `MERGE_HEAD` ref is set to point to the other branch head.
+3. Paths that merged cleanly are updated both in the index file and
+ in your working tree.
+4. For conflicting paths, the index file records up to three
+ versions: stage 1 stores the version from the common ancestor,
+ stage 2 from `HEAD`, and stage 3 from `MERGE_HEAD` (you
+ can inspect the stages with `git ls-files -u`). The working
+ tree files contain the result of the "merge" program; i.e. 3-way
+ merge results with familiar conflict markers `<<<` `===` `>>>`.
+5. No other changes are made. In particular, the local
+ modifications you had before you started merge will stay the
+ same and the index entries for them stay as they were,
+ i.e. matching `HEAD`.
+
+If you tried a merge which resulted in complex conflicts and
+want to start over, you can recover with `git merge --abort`.
+
+MERGING TAG
+-----------
+
+When merging an annotated (and possibly signed) tag, Git always
+creates a merge commit even if a fast-forward merge is possible, and
+the commit message template is prepared with the tag message.
+Additionally, if the tag is signed, the signature check is reported
+as a comment in the message template. See also linkgit:git-tag[1].
+
+When you want to just integrate with the work leading to the commit
+that happens to be tagged, e.g. synchronizing with an upstream
+release point, you may not want to make an unnecessary merge commit.
+
+In such a case, you can "unwrap" the tag yourself before feeding it
+to `git merge`, or pass `--ff-only` when you do not have any work on
+your own. e.g.
+
+----
+git fetch origin
+git merge v1.2.3^0
+git merge --ff-only v1.2.3
+----
+
+
+HOW CONFLICTS ARE PRESENTED
+---------------------------
+
+During a merge, the working tree files are updated to reflect the result
+of the merge. Among the changes made to the common ancestor's version,
+non-overlapping ones (that is, you changed an area of the file while the
+other side left that area intact, or vice versa) are incorporated in the
+final result verbatim. When both sides made changes to the same area,
+however, Git cannot randomly pick one side over the other, and asks you to
+resolve it by leaving what both sides did to that area.
+
+By default, Git uses the same style as the one used by the "merge" program
+from the RCS suite to present such a conflicted hunk, like this:
+
+------------
+Here are lines that are either unchanged from the common
+ancestor, or cleanly resolved because only one side changed.
+<<<<<<< yours:sample.txt
+Conflict resolution is hard;
+let's go shopping.
+=======
+Git makes conflict resolution easy.
+>>>>>>> theirs:sample.txt
+And here is another line that is cleanly resolved or unmodified.
+------------
+
+The area where a pair of conflicting changes happened is marked with markers
+`<<<<<<<`, `=======`, and `>>>>>>>`. The part before the `=======`
+is typically your side, and the part afterwards is typically their side.
+
+The default format does not show what the original said in the conflicting
+area. You cannot tell how many lines are deleted and replaced with
+Barbie's remark on your side. The only thing you can tell is that your
+side wants to say it is hard and you'd prefer to go shopping, while the
+other side wants to claim it is easy.
+
+An alternative style can be used by setting the "merge.conflictstyle"
+configuration variable to "diff3". In "diff3" style, the above conflict
+may look like this:
+
+------------
+Here are lines that are either unchanged from the common
+ancestor, or cleanly resolved because only one side changed.
+<<<<<<< yours:sample.txt
+Conflict resolution is hard;
+let's go shopping.
+|||||||
+Conflict resolution is hard.
+=======
+Git makes conflict resolution easy.
+>>>>>>> theirs:sample.txt
+And here is another line that is cleanly resolved or unmodified.
+------------
+
+In addition to the `<<<<<<<`, `=======`, and `>>>>>>>` markers, it uses
+another `|||||||` marker that is followed by the original text. You can
+tell that the original just stated a fact, and your side simply gave in to
+that statement and gave up, while the other side tried to have a more
+positive attitude. You can sometimes come up with a better resolution by
+viewing the original.
+
+
+HOW TO RESOLVE CONFLICTS
+------------------------
+
+After seeing a conflict, you can do two things:
+
+ * Decide not to merge. The only clean-ups you need are to reset
+ the index file to the `HEAD` commit to reverse 2. and to clean
+ up working tree changes made by 2. and 3.; `git merge --abort`
+ can be used for this.
+
+ * Resolve the conflicts. Git will mark the conflicts in
+ the working tree. Edit the files into shape and
+ 'git add' them to the index. Use 'git commit' to seal the deal.
+
+You can work through the conflict with a number of tools:
+
+ * Use a mergetool. `git mergetool` to launch a graphical
+ mergetool which will work you through the merge.
+
+ * Look at the diffs. `git diff` will show a three-way diff,
+ highlighting changes from both the `HEAD` and `MERGE_HEAD`
+ versions.
+
+ * Look at the diffs from each branch. `git log --merge -p <path>`
+ will show diffs first for the `HEAD` version and then the
+ `MERGE_HEAD` version.
+
+ * Look at the originals. `git show :1:filename` shows the
+ common ancestor, `git show :2:filename` shows the `HEAD`
+ version, and `git show :3:filename` shows the `MERGE_HEAD`
+ version.
+
+
+EXAMPLES
+--------
+
+* Merge branches `fixes` and `enhancements` on top of
+ the current branch, making an octopus merge:
++
+------------------------------------------------
+$ git merge fixes enhancements
+------------------------------------------------
+
+* Merge branch `obsolete` into the current branch, using `ours`
+ merge strategy:
++
+------------------------------------------------
+$ git merge -s ours obsolete
+------------------------------------------------
+
+* Merge branch `maint` into the current branch, but do not make
+ a new commit automatically:
++
+------------------------------------------------
+$ git merge --no-commit maint
+------------------------------------------------
++
+This can be used when you want to include further changes to the
+merge, or want to write your own merge commit message.
++
+You should refrain from abusing this option to sneak substantial
+changes into a merge commit. Small fixups like bumping
+release/version name would be acceptable.
+
+
+include::merge-strategies.txt[]
+
+CONFIGURATION
+-------------
+include::merge-config.txt[]
+
+branch.<name>.mergeoptions::
+ Sets default options for merging into branch <name>. The syntax and
+ supported options are the same as those of 'git merge', but option
+ values containing whitespace characters are currently not supported.
+
+SEE ALSO
+--------
+linkgit:git-fmt-merge-msg[1], linkgit:git-pull[1],
+linkgit:gitattributes[5],
+linkgit:git-reset[1],
+linkgit:git-diff[1], linkgit:git-ls-files[1],
+linkgit:git-add[1], linkgit:git-rm[1],
+linkgit:git-mergetool[1]
+
+GIT
+---
+Part of the linkgit:git[1] suite