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 </style>
 <title>git-rerere(1)</title>
 </head>
 <body>
 <div id="header">
 <h1>
 git-rerere(1) Manual Page
 </h1>
 <h2>NAME</h2>
 <div class="sectionbody">
 <p>git-rerere -
  Reuse recorded resolution of conflicted merges
 </p>
 </div>
 </div>
 <h2>SYNOPSIS</h2>
 <div class="sectionbody">
 <div class="para"><p><em>git rerere</em> [<em>clear</em>|<em>diff</em>|<em>status</em>|<em>gc</em>]</p></div>
 </div>
 <h2 id="_description">DESCRIPTION</h2>
 <div class="sectionbody">
 <div class="para"><p>In a workflow that employs relatively long lived topic branches,
 the developer sometimes needs to resolve the same conflict over
 and over again until the topic branches are done (either merged
 to the "release" branch, or sent out and accepted upstream).</p></div>
 <div class="para"><p>This command helps this process by recording conflicted
 automerge results and corresponding hand-resolve results on the
 initial manual merge, and later by noticing the same automerge
 results and applying the previously recorded hand resolution.</p></div>
 <div class="admonitionblock">
 <table><tr>
 <td class="icon">
 <div class="title">Note</div>
 </td>
 <td class="content">You need to set the configuration variable rerere.enabled to
 enable this command.</td>
 </tr></table>
 </div>
 </div>
 <h2 id="_commands">COMMANDS</h2>
 <div class="sectionbody">
 <div class="para"><p>Normally, <em>git-rerere</em> is run without arguments or user-intervention.
 However, it has several commands that allow it to interact with
 its working state.</p></div>
 <div class="vlist"><dl>
 <dt>
 <em>clear</em>
 </dt>
 <dd>
 <p>
 This resets the metadata used by rerere if a merge resolution is to be
 aborted. Calling <em>git-am [--skip|--abort]</em> or <em>git-rebase [--skip|--abort]</em>
 will automatically invoke this command.
 </p>
 </dd>
 <dt>
 <em>diff</em>
 </dt>
 <dd>
 <p>
 This displays diffs for the current state of the resolution. It is
 useful for tracking what has changed while the user is resolving
 conflicts. Additional arguments are passed directly to the system
 <em>diff</em> command installed in PATH.
 </p>
 </dd>
 <dt>
 <em>status</em>
 </dt>
 <dd>
 <p>
 Like <em>diff</em>, but this only prints the filenames that will be tracked
 for resolutions.
 </p>
 </dd>
 <dt>
 <em>gc</em>
 </dt>
 <dd>
 <p>
 This command is used to prune records of conflicted merge that
 occurred long time ago. By default, conflicts older than 15
 days that you have not recorded their resolution, and conflicts
 older than 60 days, are pruned. These are controlled with
 <tt>gc.rerereunresolved</tt> and <tt>gc.rerereresolved</tt> configuration
 variables.
 </p>
 </dd>
 </dl></div>
 </div>
 <h2 id="_discussion">DISCUSSION</h2>
 <div class="sectionbody">
 <div class="para"><p>When your topic branch modifies overlapping area that your
 master branch (or upstream) touched since your topic branch
 forked from it, you may want to test it with the latest master,
 even before your topic branch is ready to be pushed upstream:</p></div>
 <div class="listingblock">
 <div class="content">
 <pre><tt> o---*---o topic
  /
  o---o---o---*---o---o master</tt></pre>
 </div></div>
 <div class="para"><p>For such a test, you need to merge master and topic somehow.
 One way to do it is to pull master into the topic branch:</p></div>
 <div class="listingblock">
 <div class="content">
 <pre><tt> $ git checkout topic
  $ git merge master

  o---*---o---+ topic
  / /
  o---o---o---*---o---o master</tt></pre>
 </div></div>
 <div class="para"><p>The commits marked with <tt>*</tt> touch the same area in the same
 file; you need to resolve the conflicts when creating the commit
 marked with <tt>&#43;</tt>. Then you can test the result to make sure your
 work-in-progress still works with what is in the latest master.</p></div>
 <div class="para"><p>After this test merge, there are two ways to continue your work
 on the topic. The easiest is to build on top of the test merge
 commit <tt>&#43;</tt>, and when your work in the topic branch is finally
 ready, pull the topic branch into master, and/or ask the
 upstream to pull from you. By that time, however, the master or
 the upstream might have been advanced since the test merge <tt>&#43;</tt>,
 in which case the final commit graph would look like this:</p></div>
 <div class="listingblock">
 <div class="content">
 <pre><tt> $ git checkout topic
  $ git merge master
  $ ... work on both topic and master branches
  $ git checkout master
  $ git merge topic

  o---*---o---+---o---o topic
  / / \
  o---o---o---*---o---o---o---o---+ master</tt></pre>
 </div></div>
 <div class="para"><p>When your topic branch is long-lived, however, your topic branch
 would end up having many such "Merge from master" commits on it,
 which would unnecessarily clutter the development history.
 Readers of the Linux kernel mailing list may remember that Linus
 complained about such too frequent test merges when a subsystem
 maintainer asked to pull from a branch full of "useless merges".</p></div>
 <div class="para"><p>As an alternative, to keep the topic branch clean of test
 merges, you could blow away the test merge, and keep building on
 top of the tip before the test merge:</p></div>
 <div class="listingblock">
 <div class="content">
 <pre><tt> $ git checkout topic
  $ git merge master
  $ git reset --hard HEAD^ ;# rewind the test merge
  $ ... work on both topic and master branches
  $ git checkout master
  $ git merge topic

  o---*---o-------o---o topic
  / \
  o---o---o---*---o---o---o---o---+ master</tt></pre>
 </div></div>
 <div class="para"><p>This would leave only one merge commit when your topic branch is
 finally ready and merged into the master branch. This merge
 would require you to resolve the conflict, introduced by the
 commits marked with <tt>*</tt>. However, often this conflict is the
 same conflict you resolved when you created the test merge you
 blew away. <em>git-rerere</em> command helps you to resolve this final
 conflicted merge using the information from your earlier hand
 resolve.</p></div>
 <div class="para"><p>Running the <em>git-rerere</em> command immediately after a conflicted
 automerge records the conflicted working tree files, with the
 usual conflict markers <tt>&lt;&lt;&lt;&lt;&lt;&lt;&lt;</tt>, <tt>=======</tt>, and <tt>&gt;&gt;&gt;&gt;&gt;&gt;&gt;</tt> in
 them. Later, after you are done resolving the conflicts,
 running <em>git-rerere</em> again records the resolved state of these
 files. Suppose you did this when you created the test merge of
 master into the topic branch.</p></div>
 <div class="para"><p>Next time, running <em>git-rerere</em> after seeing a conflicted
 automerge, if the conflict is the same as the earlier one
 recorded, it is noticed and a three-way merge between the
 earlier conflicted automerge, the earlier manual resolution, and
 the current conflicted automerge is performed by the command.
 If this three-way merge resolves cleanly, the result is written
 out to your working tree file, so you would not have to manually
 resolve it. Note that <em>git-rerere</em> leaves the index file alone,
 so you still need to do the final sanity checks with <tt>git diff</tt>
 (or <tt>git diff -c</tt>) and <em>git-add</em> when you are satisfied.</p></div>
 <div class="para"><p>As a convenience measure, <em>git-merge</em> automatically invokes
 <em>git-rerere</em> when it exits with a failed automerge, which
 records it if it is a new conflict, or reuses the earlier hand
 resolve when it is not. <em>git-commit</em> also invokes <em>git-rerere</em>
 when recording a merge result. What this means is that you do
 not have to do anything special yourself (Note: you still have
 to set the config variable rerere.enabled to enable this command).</p></div>
 <div class="para"><p>In our example, when you did the test merge, the manual
 resolution is recorded, and it will be reused when you do the
 actual merge later with updated master and topic branch, as long
 as the earlier resolution is still applicable.</p></div>
 <div class="para"><p>The information <em>git-rerere</em> records is also used when running
 <em>git-rebase</em>. After blowing away the test merge and continuing
 development on the topic branch:</p></div>
 <div class="listingblock">
 <div class="content">
 <pre><tt> o---*---o-------o---o topic
  /
  o---o---o---*---o---o---o---o master

  $ git rebase master topic

  o---*---o-------o---o topic
  /
  o---o---o---*---o---o---o---o master</tt></pre>
 </div></div>
 <div class="para"><p>you could run <tt>git rebase master topic</tt>, to keep yourself
 up-to-date even before your topic is ready to be sent upstream.
 This would result in falling back to three-way merge, and it
 would conflict the same way the test merge you resolved earlier.
 <em>git-rerere</em> is run by <em>git-rebase</em> to help you resolve this
 conflict.</p></div>
 </div>
 <h2 id="_author">Author</h2>
 <div class="sectionbody">
 <div class="para"><p>Written by Junio C Hamano &lt;gitster@pobox.com&gt;</p></div>
 </div>
 <h2 id="_git">GIT</h2>
 <div class="sectionbody">
 <div class="para"><p>Part of the <a href="git.html">git(1)</a> suite</p></div>
 </div>
 <div id="footer">
 <div id="footer-text">
 Last updated 2008-08-10 03:55:20 UTC
 </div>
 </div>
 </body>
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	<title>git-rerere(1)</title>
	</head>
	<body>
	<div id="header">
	<h1>
	git-rerere(1) Manual Page
	</h1>
	<h2>NAME</h2>
	<div class="sectionbody">
	<p>git-rerere -
	Reuse recorded resolution of conflicted merges
	</p>
	</div>
	</div>
	<h2>SYNOPSIS</h2>
	<div class="sectionbody">
	<div class="para"><p><em>git rerere</em> [<em>clear</em>\|<em>diff</em>\|<em>status</em>\|<em>gc</em>]</p></div>
	</div>
	<h2 id="_description">DESCRIPTION</h2>
	<div class="sectionbody">
	<div class="para"><p>In a workflow that employs relatively long lived topic branches,
	the developer sometimes needs to resolve the same conflict over
	and over again until the topic branches are done (either merged
	to the "release" branch, or sent out and accepted upstream).</p></div>
	<div class="para"><p>This command helps this process by recording conflicted
	automerge results and corresponding hand-resolve results on the
	initial manual merge, and later by noticing the same automerge
	results and applying the previously recorded hand resolution.</p></div>
	<div class="admonitionblock">
	<table><tr>
	<td class="icon">
	<div class="title">Note</div>
	</td>
	<td class="content">You need to set the configuration variable rerere.enabled to
	enable this command.</td>
	</tr></table>
	</div>
	</div>
	<h2 id="_commands">COMMANDS</h2>
	<div class="sectionbody">
	<div class="para"><p>Normally, <em>git-rerere</em> is run without arguments or user-intervention.
	However, it has several commands that allow it to interact with
	its working state.</p></div>
	<div class="vlist"><dl>
	<dt>
	<em>clear</em>
	</dt>
	<dd>
	<p>
	This resets the metadata used by rerere if a merge resolution is to be
	aborted. Calling <em>git-am [--skip\|--abort]</em> or <em>git-rebase [--skip\|--abort]</em>
	will automatically invoke this command.
	</p>
	</dd>
	<dt>
	<em>diff</em>
	</dt>
	<dd>
	<p>
	This displays diffs for the current state of the resolution. It is
	useful for tracking what has changed while the user is resolving
	conflicts. Additional arguments are passed directly to the system
	<em>diff</em> command installed in PATH.
	</p>
	</dd>
	<dt>
	<em>status</em>
	</dt>
	<dd>
	<p>
	Like <em>diff</em>, but this only prints the filenames that will be tracked
	for resolutions.
	</p>
	</dd>
	<dt>
	<em>gc</em>
	</dt>
	<dd>
	<p>
	This command is used to prune records of conflicted merge that
	occurred long time ago. By default, conflicts older than 15
	days that you have not recorded their resolution, and conflicts
	older than 60 days, are pruned. These are controlled with
	<tt>gc.rerereunresolved</tt> and <tt>gc.rerereresolved</tt> configuration
	variables.
	</p>
	</dd>
	</dl></div>
	</div>
	<h2 id="_discussion">DISCUSSION</h2>
	<div class="sectionbody">
	<div class="para"><p>When your topic branch modifies overlapping area that your
	master branch (or upstream) touched since your topic branch
	forked from it, you may want to test it with the latest master,
	even before your topic branch is ready to be pushed upstream:</p></div>
	<div class="listingblock">
	<div class="content">
	<pre><tt> o---*---o topic
	/
	o---o---o---*---o---o master</tt></pre>
	</div></div>
	<div class="para"><p>For such a test, you need to merge master and topic somehow.
	One way to do it is to pull master into the topic branch:</p></div>
	<div class="listingblock">
	<div class="content">
	<pre><tt> $ git checkout topic
	$ git merge master

	o---*---o---+ topic
	/ /
	o---o---o---*---o---o master</tt></pre>
	</div></div>
	<div class="para"><p>The commits marked with <tt>*</tt> touch the same area in the same
	file; you need to resolve the conflicts when creating the commit
	marked with <tt>+</tt>. Then you can test the result to make sure your
	work-in-progress still works with what is in the latest master.</p></div>
	<div class="para"><p>After this test merge, there are two ways to continue your work
	on the topic. The easiest is to build on top of the test merge
	commit <tt>+</tt>, and when your work in the topic branch is finally
	ready, pull the topic branch into master, and/or ask the
	upstream to pull from you. By that time, however, the master or
	the upstream might have been advanced since the test merge <tt>+</tt>,
	in which case the final commit graph would look like this:</p></div>
	<div class="listingblock">
	<div class="content">
	<pre><tt> $ git checkout topic
	$ git merge master
	$ ... work on both topic and master branches
	$ git checkout master
	$ git merge topic

	o---*---o---+---o---o topic
	/ / \
	o---o---o---*---o---o---o---o---+ master</tt></pre>
	</div></div>
	<div class="para"><p>When your topic branch is long-lived, however, your topic branch
	would end up having many such "Merge from master" commits on it,
	which would unnecessarily clutter the development history.
	Readers of the Linux kernel mailing list may remember that Linus
	complained about such too frequent test merges when a subsystem
	maintainer asked to pull from a branch full of "useless merges".</p></div>
	<div class="para"><p>As an alternative, to keep the topic branch clean of test
	merges, you could blow away the test merge, and keep building on
	top of the tip before the test merge:</p></div>
	<div class="listingblock">
	<div class="content">
	<pre><tt> $ git checkout topic
	$ git merge master
	$ git reset --hard HEAD^ ;# rewind the test merge
	$ ... work on both topic and master branches
	$ git checkout master
	$ git merge topic

	o---*---o-------o---o topic
	/ \
	o---o---o---*---o---o---o---o---+ master</tt></pre>
	</div></div>
	<div class="para"><p>This would leave only one merge commit when your topic branch is
	finally ready and merged into the master branch. This merge
	would require you to resolve the conflict, introduced by the
	commits marked with <tt>*</tt>. However, often this conflict is the
	same conflict you resolved when you created the test merge you
	blew away. <em>git-rerere</em> command helps you to resolve this final
	conflicted merge using the information from your earlier hand
	resolve.</p></div>
	<div class="para"><p>Running the <em>git-rerere</em> command immediately after a conflicted
	automerge records the conflicted working tree files, with the
	usual conflict markers <tt><<<<<<<</tt>, <tt>=======</tt>, and <tt>>>>>>>></tt> in
	them. Later, after you are done resolving the conflicts,
	running <em>git-rerere</em> again records the resolved state of these
	files. Suppose you did this when you created the test merge of
	master into the topic branch.</p></div>
	<div class="para"><p>Next time, running <em>git-rerere</em> after seeing a conflicted
	automerge, if the conflict is the same as the earlier one
	recorded, it is noticed and a three-way merge between the
	earlier conflicted automerge, the earlier manual resolution, and
	the current conflicted automerge is performed by the command.
	If this three-way merge resolves cleanly, the result is written
	out to your working tree file, so you would not have to manually
	resolve it. Note that <em>git-rerere</em> leaves the index file alone,
	so you still need to do the final sanity checks with <tt>git diff</tt>
	(or <tt>git diff -c</tt>) and <em>git-add</em> when you are satisfied.</p></div>
	<div class="para"><p>As a convenience measure, <em>git-merge</em> automatically invokes
	<em>git-rerere</em> when it exits with a failed automerge, which
	records it if it is a new conflict, or reuses the earlier hand
	resolve when it is not. <em>git-commit</em> also invokes <em>git-rerere</em>
	when recording a merge result. What this means is that you do
	not have to do anything special yourself (Note: you still have
	to set the config variable rerere.enabled to enable this command).</p></div>
	<div class="para"><p>In our example, when you did the test merge, the manual
	resolution is recorded, and it will be reused when you do the
	actual merge later with updated master and topic branch, as long
	as the earlier resolution is still applicable.</p></div>
	<div class="para"><p>The information <em>git-rerere</em> records is also used when running
	<em>git-rebase</em>. After blowing away the test merge and continuing
	development on the topic branch:</p></div>
	<div class="listingblock">
	<div class="content">
	<pre><tt> o---*---o-------o---o topic
	/
	o---o---o---*---o---o---o---o master

	$ git rebase master topic

	o---*---o-------o---o topic
	/
	o---o---o---*---o---o---o---o master</tt></pre>
	</div></div>
	<div class="para"><p>you could run <tt>git rebase master topic</tt>, to keep yourself
	up-to-date even before your topic is ready to be sent upstream.
	This would result in falling back to three-way merge, and it
	would conflict the same way the test merge you resolved earlier.
	<em>git-rerere</em> is run by <em>git-rebase</em> to help you resolve this
	conflict.</p></div>
	</div>
	<h2 id="_author">Author</h2>
	<div class="sectionbody">
	<div class="para"><p>Written by Junio C Hamano <gitster@pobox.com></p></div>
	</div>
	<h2 id="_git">GIT</h2>
	<div class="sectionbody">
	<div class="para"><p>Part of the <a href="git.html">git(1)</a> suite</p></div>
	</div>
	<div id="footer">
	<div id="footer-text">
	Last updated 2008-08-10 03:55:20 UTC
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