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+Git 2.8 Release Notes
+=====================
+
+Backward compatibility note
+---------------------------
+
+The rsync:// transport has been removed.
+
+
+Updates since v2.7
+------------------
+
+UI, Workflows & Features
+
+ * It turns out "git clone" over rsync transport has been broken when
+   the source repository has packed references for a long time, and
+   nobody noticed nor complained about it.
+
+ * "push" learned that its "--delete" option can be shortened to
+   "-d", just like "branch --delete" and "branch -d" are the same
+   thing.
+
+ * "git blame" learned to produce the progress eye-candy when it takes
+   too much time before emitting the first line of the result.
+
+ * "git grep" can now be configured (or told from the command line)
+   how many threads to use when searching in the working tree files.
+
+ * Some "git notes" operations, e.g. "git log --notes=<note>", should
+   be able to read notes from any tree-ish that is shaped like a notes
+   tree, but the notes infrastructure required that the argument must
+   be a ref under refs/notes/.  Loosen it to require a valid ref only
+   when the operation would update the notes (in which case we must
+   have a place to store the updated notes tree, iow, a ref).
+
+ * "git grep" by default does not fall back to its "--no-index"
+   behavior outside a directory under Git's control (otherwise the
+   user may by mistake end up running a huge recursive search); with a
+   new configuration (set in $HOME/.gitconfig--by definition this
+   cannot be set in the config file per project), this safety can be
+   disabled.
+
+ * "git pull --rebase" has been extended to allow invoking
+   "rebase -i".
+
+ * "git p4" learned to cope with the type of a file getting changed.
+
+ * "git format-patch" learned to notice format.outputDirectory
+   configuration variable.  This allows "-o <dir>" option to be
+   omitted on the command line if you always use the same directory in
+   your workflow.
+
+ * "interpret-trailers" has been taught to optionally update a file in
+   place, instead of always writing the result to the standard output.
+
+ * Many commands that read files that are expected to contain text
+   that is generated (or can be edited) by the end user to control
+   their behavior (e.g. "git grep -f <filename>") have been updated
+   to be more tolerant to lines that are terminated with CRLF (they
+   used to treat such a line to contain payload that ends with CR,
+   which is usually not what the users expect).
+
+ * "git notes merge" used to limit the source of the merged notes tree
+   to somewhere under refs/notes/ hierarchy, which was too limiting
+   when inventing a workflow to exchange notes with remote
+   repositories using remote-tracking notes trees (located in e.g.
+   refs/remote-notes/ or somesuch).
+
+ * "git ls-files" learned a new "--eol" option to help diagnose
+   end-of-line problems.
+
+ * "ls-remote" learned an option to show which branch the remote
+   repository advertises as its primary by pointing its HEAD at.
+
+ * New http.proxyAuthMethod configuration variable can be used to
+   specify what authentication method to use, as a way to work around
+   proxies that do not give error response expected by libcurl when
+   CURLAUTH_ANY is used.  Also, the codepath for proxy authentication
+   has been taught to use credential API to store the authentication
+   material in user's keyrings.
+
+ * Update the untracked cache subsystem and change its primary UI from
+   "git update-index" to "git config".
+
+ * There were a few "now I am doing this thing" progress messages in
+   the TCP connection code that can be triggered by setting a verbose
+   option internally in the code, but "git fetch -v" and friends never
+   passed the verbose option down to that codepath.
+
+ * Clean/smudge filters defined in a configuration file of lower
+   precedence can now be overridden to be a pass-through no-op by
+   setting the variable to an empty string.
+
+ * A new "<branch>^{/!-<pattern>}" notation can be used to name a
+   commit that is reachable from <branch> that does not match the
+   given <pattern>.
+
+ * The "user.useConfigOnly" configuration variable can be used to
+   force the user to always set user.email & user.name configuration
+   variables, serving as a reminder for those who work on multiple
+   projects and do not want to put these in their $HOME/.gitconfig.
+
+ * "git fetch" and friends that make network connections can now be
+   told to only use ipv4 (or ipv6).
+
+ * Some authentication methods do not need username or password, but
+   libcurl needs some hint that it needs to perform authentication.
+   Supplying an empty username and password string is a valid way to
+   do so, but you can set the http.[<url>.]emptyAuth configuration
+   variable to achieve the same, if you find it cleaner.
+
+ * You can now set http.[<url>.]pinnedpubkey to specify the pinned
+   public key when building with recent enough versions of libcURL.
+
+ * The configuration system has been taught to phrase where it found a
+   bad configuration variable in a better way in its error messages.
+   "git config" learnt a new "--show-origin" option to indicate where
+   the values come from.
+
+ * The "credential-cache" daemon process used to run in whatever
+   directory it happened to start in, but this made umount(2)ing the
+   filesystem that houses the repository harder; now the process
+   chdir()s to the directory that house its own socket on startup.
+
+ * When "git submodule update" did not result in fetching the commit
+   object in the submodule that is referenced by the superproject, the
+   command learned to retry another fetch, specifically asking for
+   that commit that may not be connected to the refs it usually
+   fetches.
+
+ * "git merge-recursive" learned "--no-renames" option to disable its
+   rename detection logic.
+
+ * Across the transition at around Git version 2.0, the user used to
+   get a pretty loud warning when running "git push" without setting
+   push.default configuration variable.  We no longer warn because the
+   transition was completed a long time ago.
+
+ * README has been renamed to README.md and its contents got tweaked
+   slightly to make it easier on the eyes.
+
+
+Performance, Internal Implementation, Development Support etc.
+
+ * Add a framework to spawn a group of processes in parallel, and use
+   it to run "git fetch --recurse-submodules" in parallel.
+
+ * A slight update to the Makefile to mark ".PHONY" targets as such
+   correctly.
+
+ * In-core storage of the reverse index for .pack files (which lets
+   you go from a pack offset to an object name) has been streamlined.
+
+ * d95138e6 (setup: set env $GIT_WORK_TREE when work tree is set, like
+   $GIT_DIR, 2015-06-26) attempted to work around a glitch in alias
+   handling by overwriting GIT_WORK_TREE environment variable to
+   affect subprocesses when set_git_work_tree() gets called, which
+   resulted in a rather unpleasant regression to "clone" and "init".
+   Try to address the same issue by always restoring the environment
+   and respawning the real underlying command when handling alias.
+
+ * The low-level code that is used to create symbolic references has
+   been updated to share more code with the code that deals with
+   normal references.
+
+ * strbuf_getline() and friends have been redefined to make it easier
+   to identify which callsite of (new) strbuf_getline_lf() should
+   allow and silently ignore carriage-return at the end of the line to
+   help users on DOSsy systems.
+
+ * "git shortlog" used to accumulate various pieces of information
+   regardless of what was asked to be shown in the final output.  It
+   has been optimized by noticing what need not to be collected
+   (e.g. there is no need to collect the log messages when showing
+   only the number of changes).
+
+ * "git checkout $branch" (and other operations that share the same
+   underlying machinery) has been optimized.
+
+ * Automated tests in Travis CI environment has been optimized by
+   persisting runtime statistics of previous "prove" run, executing
+   tests that take longer before other ones; this reduces the total
+   wallclock time.
+
+ * Test scripts have been updated to remove assumptions that are not
+   portable between Git for POSIX and Git for Windows, or to skip ones
+   with expectations that are not satisfiable on Git for Windows.
+
+ * Some calls to strcpy(3) triggers a false warning from static
+   analyzers that are less intelligent than humans, and reducing the
+   number of these false hits helps us notice real issues.  A few
+   calls to strcpy(3) in a couple of protrams that are already safe
+   has been rewritten to avoid false warnings.
+
+ * The "name_path" API was an attempt to reduce the need to construct
+   the full path out of a series of path components while walking a
+   tree hierarchy, but over time made less efficient because the path
+   needs to be flattened, e.g. to be compared with another path that
+   is already flat.  The API has been removed and its users have been
+   rewritten to simplify the overall code complexity.
+
+ * Help those who debug http(s) part of the system.
+   (merge 0054045 sp/remote-curl-ssl-strerror later to maint).
+
+ * The internal API to interact with "remote.*" configuration
+   variables has been streamlined.
+
+ * The ref-filter's format-parsing code has been refactored, in
+   preparation for "branch --format" and friends.
+
+ * Traditionally, the tests that try commands that work on the
+   contents in the working tree were named with "worktree" in their
+   filenames, but with the recent addition of "git worktree"
+   subcommand, whose tests are also named similarly, it has become
+   harder to tell them apart.  The traditional tests have been renamed
+   to use "work-tree" instead in an attempt to differentiate them.
+   (merge 5549029 mg/work-tree-tests later to maint).
+
+ * Many codepaths forget to check return value from git_config_set();
+   the function is made to die() to make sure we do not proceed when
+   setting a configuration variable failed.
+   (merge 3d18064 ps/config-error later to maint).
+
+ * Handling of errors while writing into our internal asynchronous
+   process has been made more robust, which reduces flakiness in our
+   tests.
+   (merge 43f3afc jk/epipe-in-async later to maint).
+
+ * There is a new DEVELOPER knob that enables many compiler warning
+   options in the Makefile.
+
+ * The way the test scripts configure the Apache web server has been
+   updated to work also for Apache 2.4 running on RedHat derived
+   distros.
+
+ * Out of maintenance gcc on OSX 10.6 fails to compile the code in
+   'master'; work it around by using clang by default on the platform.
+
+ * The "name_path" API was an attempt to reduce the need to construct
+   the full path out of a series of path components while walking a
+   tree hierarchy, but over time made less efficient because the path
+   needs to be flattened, e.g. to be compared with another path that
+   is already flat, in many cases.  The API has been removed and its
+   users have been rewritten to simplify the overall code complexity.
+   This incidentally also closes some heap-corruption holes.
+
+ * Recent versions of GNU grep is pickier than before to decide if a
+   file is "binary" and refuse to give line-oriented hits when we
+   expect it to, unless explicitly told with "-a" option.  As our
+   scripted Porcelains use sane_grep wrapper for line-oriented data,
+   even when the line may contain non-ASCII payload we took from
+   end-user data, use "grep -a" to implement sane_grep wrapper when
+   using an implementation of "grep" that takes the "-a" option.
+
+
+
+Also contains various documentation updates and code clean-ups.
+
+
+Fixes since v2.7
+----------------
+
+Unless otherwise noted, all the fixes since v2.7 in the maintenance
+track are contained in this release (see the maintenance releases'
+notes for details).
+
+ * An earlier change in 2.5.x-era broke users' hooks and aliases by
+   exporting GIT_WORK_TREE to point at the root of the working tree,
+   interfering when they tried to use a different working tree without
+   setting GIT_WORK_TREE environment themselves.
+
+ * The "exclude_list" structure has the usual "alloc, nr" pair of
+   fields to be used by ALLOC_GROW(), but clear_exclude_list() forgot
+   to reset 'alloc' to 0 when it cleared 'nr' to discard the managed
+   array.
+
+ * Paths that have been told the index about with "add -N" are not
+   quite yet in the index, but a few commands behaved as if they
+   already are in a harmful way.
+
+ * "git send-email" was confused by escaped quotes stored in the alias
+   files saved by "mutt", which has been corrected.
+
+ * A few non-portable C construct have been spotted by clang compiler
+   and have been fixed.
+
+ * The documentation has been updated to hint the connection between
+   the '--signoff' option and DCO.
+
+ * "git reflog" incorrectly assumed that all objects that used to be
+   at the tip of a ref must be commits, which caused it to segfault.
+
+ * The ignore mechanism saw a few regressions around untracked file
+   listing and sparse checkout selection areas in 2.7.0; the change
+   that is responsible for the regression has been reverted.
+
+ * Some codepaths used fopen(3) when opening a fixed path in $GIT_DIR
+   (e.g. COMMIT_EDITMSG) that is meant to be left after the command is
+   done.  This however did not work well if the repository is set to
+   be shared with core.sharedRepository and the umask of the previous
+   user is tighter.  They have been made to work better by calling
+   unlink(2) and retrying after fopen(3) fails with EPERM.
+
+ * Asking gitweb for a nonexistent commit left a warning in the server
+   log.
+
+   Somebody may want to follow this up with an additional test, perhaps?
+   IIRC, we do test that no Perl warnings are given to the server log,
+   so this should have been caught if our test coverage were good.
+
+ * "git rebase", unlike all other callers of "gc --auto", did not
+   ignore the exit code from "gc --auto".
+
+ * Many codepaths that run "gc --auto" before exiting kept packfiles
+   mapped and left the file descriptors to them open, which was not
+   friendly to systems that cannot remove files that are open.  They
+   now close the packs before doing so.
+
+ * A recent optimization to filter-branch in v2.7.0 introduced a
+   regression when --prune-empty filter is used, which has been
+   corrected.
+
+ * The description for SANITY prerequisite the test suite uses has
+   been clarified both in the comment and in the implementation.
+
+ * "git tag" started listing a tag "foo" as "tags/foo" when a branch
+   named "foo" exists in the same repository; remove this unnecessary
+   disambiguation, which is a regression introduced in v2.7.0.
+
+ * The way "git svn" uses auth parameter was broken by Subversion
+   1.9.0 and later.
+
+ * The "split" subcommand of "git subtree" (in contrib/) incorrectly
+   skipped merges when it shouldn't, which was corrected.
+
+ * A few options of "git diff" did not work well when the command was
+   run from a subdirectory.
+
+ * The command line completion learned a handful of additional options
+   and command specific syntax.
+
+ * dirname() emulation has been added, as Msys2 lacks it.
+
+ * The underlying machinery used by "ls-files -o" and other commands
+   has been taught not to create empty submodule ref cache for a
+   directory that is not a submodule.  This removes a ton of wasted
+   CPU cycles.
+
+ * "git worktree" had a broken code that attempted to auto-fix
+   possible inconsistency that results from end-users moving a
+   worktree to different places without telling Git (the original
+   repository needs to maintain back-pointers to its worktrees,
+   but "mv" run by end-users who are not familiar with that fact
+   will obviously not adjust them), which actually made things
+   worse when triggered.
+
+ * The low-level merge machinery has been taught to use CRLF line
+   termination when inserting conflict markers to merged contents that
+   are themselves CRLF line-terminated.
+
+ * "git push --force-with-lease" has been taught to report if the push
+   needed to force (or fast-forwarded).
+
+ * The emulated "yes" command used in our test scripts has been
+   tweaked not to spend too much time generating unnecessary output
+   that is not used, to help those who test on Windows where it would
+   not stop until it fills the pipe buffer due to lack of SIGPIPE.
+
+ * The documentation for "git clean" has been corrected; it mentioned
+   that .git/modules/* are removed by giving two "-f", which has never
+   been the case.
+
+ * The vimdiff backend for "git mergetool" has been tweaked to arrange
+   and number buffers in the order that would match the expectation of
+   majority of people who read left to right, then top down and assign
+   buffers 1 2 3 4 "mentally" to local base remote merge windows based
+   on that order.
+
+ * "git show 'HEAD:Foo[BAR]Baz'" did not interpret the argument as a
+   rev, i.e. the object named by the the pathname with wildcard
+   characters in a tree object.
+   (merge aac4fac nd/dwim-wildcards-as-pathspecs later to maint).
+
+ * "git rev-parse --git-common-dir" used in the worktree feature
+   misbehaved when run from a subdirectory.
+   (merge 17f1365 nd/git-common-dir-fix later to maint).
+
+ * "git worktree add -B <branchname>" did not work.
+
+ * The "v(iew)" subcommand of the interactive "git am -i" command was
+   broken in 2.6.0 timeframe when the command was rewritten in C.
+   (merge 708b8cc jc/am-i-v-fix later to maint).
+
+ * "git merge-tree" used to mishandle "both sides added" conflict with
+   its own "create a fake ancestor file that has the common parts of
+   what both sides have added and do a 3-way merge" logic; this has
+   been updated to use the usual "3-way merge with an empty blob as
+   the fake common ancestor file" approach used in the rest of the
+   system.
+   (merge 907681e jk/no-diff-emit-common later to maint).
+
+ * The memory ownership rule of fill_textconv() API, which was a bit
+   tricky, has been documented a bit better.
+   (merge a64e6a4 jk/more-comments-on-textconv later to maint).
+
+ * Update various codepaths to avoid manually-counted malloc().
+   (merge 08c95df jk/tighten-alloc later to maint).
+
+ * The documentation did not clearly state that the 'simple' mode is
+   now the default for "git push" when push.default configuration is
+   not set.
+   (merge f6b1fb3 mm/push-simple-doc later to maint).
+
+ * Recent versions of GNU grep are pickier when their input contains
+   arbitrary binary data, which some of our tests uses.  Rewrite the
+   tests to sidestep the problem.
+   (merge 3b1442d jk/grep-binary-workaround-in-test later to maint).
+
+ * A helper function "git submodule" uses since v2.7.0 to list the
+   modules that match the pathspec argument given to its subcommands
+   (e.g. "submodule add <repo> <path>") has been fixed.
+   (merge 2b56bb7 sb/submodule-module-list-fix later to maint).
+
+ * "git config section.var value" to set a value in per-repository
+   configuration file failed when it was run outside any repository,
+   but didn't say the reason correctly.
+   (merge 638fa62 js/config-set-in-non-repository later to maint).
+
+ * The code to read the pack data using the offsets stored in the pack
+   idx file has been made more carefully check the validity of the
+   data in the idx.
+   (merge 7465feb jk/pack-idx-corruption-safety later to maint).
+
+ * Other minor clean-ups and documentation updates
+   (merge f459823 ak/extract-argv0-last-dir-sep later to maint).
+   (merge 63ca1c0 ak/git-strip-extension-from-dashed-command later to maint).
+   (merge 4867f11 ps/plug-xdl-merge-leak later to maint).
+   (merge 4938686 dt/initial-ref-xn-commit-doc later to maint).
+   (merge 9537f21 ma/update-hooks-sample-typofix later to maint).