Log message:
git: updated to 2.16.1

Git v2.16.1 Release Notes

Fixes since v2.16
* "git clone" segfaulted when cloning a project that happens to
  track two paths that differ only in case on a case insensitive
  filesystem.

Log message:
git: updated to 2.16.0

Git 2.16 Release Notes
Backward compatibility notes and other notable changes.
 * Use of an empty string as a pathspec element that is used for
   'everything matches' is now an error.

Updates since v2.15
UI, Workflows & Features

 * An empty string as a pathspec element that means "everything"
   i.e. 'git add ""', is now illegal.  We started this by first
   deprecating and warning a pathspec that has such an element in
   2.11 (Nov 2016).

 * A hook script that is set unexecutable is simply ignored.  Git
   notifies when such a file is ignored, unless the message is
   squelched via advice.ignoredHook configuration.

 * "git pull" has been taught to accept "--[no-]signoff" \ 
option and
   pass it down to "git merge".

 * The "--push-option=<string>" option to "git push" \ 
now defaults to a
   list of strings configured via push.pushOption variable.

 * "gitweb" checks if a directory is searchable with Perl's "-x"
   operator, which can be enhanced by using "filetest 'access'"
   pragma, which now we do.

 * "git stash save" has been deprecated in favour of "git stash \ 
push".

 * The set of paths output from "git status --ignored" was tied
   closely with its "--untracked=<mode>" option, but now it can be
   controlled more flexibly.  Most notably, a directory that is
   ignored because it is listed to be ignored in the ignore/exclude
   mechanism can be handled differently from a directory that ends up
   to be ignored only because all files in it are ignored.

 * The remote-helper for talking to MediaWiki has been updated to
   truncate an overlong pagename so that ".mw" suffix can still be
   added.

 * The remote-helper for talking to MediaWiki has been updated to
   work with mediawiki namespaces.

 * The "--format=..." option "git for-each-ref" takes \ 
learned to show
   the name of the 'remote' repository and the ref at the remote side
   that is affected for 'upstream' and 'push' via "%(push:remotename)"
   and friends.

 * Doc and message updates to teach users "bisect view" is a synonym
   for "bisect visualize".

 * "git bisect run" that did not specify any command to run used to go
   ahead and treated all commits to be tested as 'good'.  This has
   been corrected by making the command error out.

 * The SubmittingPatches document has been converted to produce an
   HTML version via AsciiDoc/Asciidoctor.

 * We learned to optionally talk to a file system monitor via new
   fsmonitor extension to speed up "git status" and other operations
   that need to see which paths have been modified.  Currently we only
   support "watchman".  See File System Monitor section of
   git-update-index(1) for more detail.

 * The "diff" family of commands learned to ignore differences in
   carriage return at the end of line.

 * Places that know about "sendemail.to", like documentation and shell
   completion (in contrib/) have been taught about "sendemail.tocmd",
   too.

 * "git add --renormalize ." is a new and safer way to record the fact
   that you are correcting the end-of-line convention and other
   "convert_to_git()" glitches in the in-repository data.

 * "git branch" and "git checkout -b" are now forbidden from \ 
creating
   a branch whose name is "HEAD".

 * "git branch --list" learned to show its output through the pager by
   default when the output is going to a terminal, which is controlled
   by the pager.branch configuration variable.  This is similar to a
   recent change to "git tag --list".

 * "git grep -W", "git diff -W" and their friends learned a \ 
heuristic
   to extend a pre-context beyond the line that matches the "function
   pattern" (aka "diff.*.xfuncname") to include a comment block, if
   exists, that immediately precedes it.

 * "git config --expiry-date gc.reflogexpire" can read \ 
"2.weeks" from
   the configuration and report it as a timestamp, just like "--int"
   would read "1k" and report 1024, to help consumption by scripts.

 * The shell completion (in contrib/) learned that "git pull" can take
   the "--autostash" option.

 * The tagnames "git log --decorate" uses to annotate the commits can
   now be limited to subset of available refs with the two additional
   options, --decorate-refs[-exclude]=<pattern>.

 * "git grep" compiled with libpcre2 sometimes triggered a segfault,
   which is being fixed.

 * "git send-email" tries to see if the sendmail program is available
   in /usr/lib and /usr/sbin; extend the list of locations to be
   checked to also include directories on $PATH.

 * "git diff" learned, "--anchored", a variant of the \ 
"--patience"
   algorithm, to which the user can specify which 'unique' line to be
   used as anchoring points.

 * The way "git worktree add" determines what branch to create from
   where and checkout in the new worktree has been updated a bit.

 * Ancient part of codebase still shows dots after an abbreviated
   object name just to show that it is not a full object name, but
   these ellipses are confusing to people who newly discovered Git
   who are used to seeing abbreviated object names and find them
   confusing with the range syntax.

 * With a configuration variable rebase.abbreviateCommands set,
   "git rebase -i" produces the todo list with a single-letter
   command names.

 * "git worktree add" learned to run the post-checkout hook, just like
   "git checkout" does, after the initial checkout.

 * "git svn" has been updated to strip CRs in the commit messages, as
   recent versions of Subversion rejects them.

 * "git imap-send" did not correctly quote the folder name when
   making a request to the server, which has been corrected.

 * Error messages from "git rebase" have been somewhat cleaned up.

 * Git has been taught to support an https:// URL used for http.proxy
   when using recent versions of libcurl.

 * "git merge" learned to pay attention to merge.verifySignatures
   configuration variable and pretend as if '--verify-signatures'
   option was given from the command line.

 * "git describe" was taught to dig trees deeper to find a
   <commit-ish>:<path> that refers to a given blob object.

Log message:
git: updated to 2.15.1

Git v2.15.1 Release Notes

Fixes since v2.15
-----------------

 * TravisCI build updates.

 * "auto" as a value for the columnar output configuration ought to
   judge "is the output consumed by humans?" with the same criteria as
   "auto" for coloured output configuration, i.e. either the standard
   output stream is going to tty, or a pager is in use.  We forgot the
   latter, which has been fixed.

 * The experimental "color moved lines differently in diff output"
   feature was buggy around "ignore whitespace changes" edges, which
   has been corrected.

 * Instead of using custom line comparison and hashing functions to
   implement "moved lines" coloring in the diff output, use the pair
   of these functions from lower-layer xdiff/ code.

 * Some codepaths did not check for errors when asking what branch the
   HEAD points at, which have been fixed.

 * "git commit", after making a commit, did not check for errors when
   asking on what branch it made the commit, which has been corrected.

 * "git status --ignored -u" did not stop at a working tree of a
   separate project that is embedded in an ignored directory and
   listed files in that other project, instead of just showing the
   directory itself as ignored.

 * A broken access to object databases in recent update to "git grep
   --recurse-submodules" has been fixed.

 * A recent regression in "git rebase -i" that broke execution of git
   commands from subdirectories via "exec" instruction has been fixed.

 * "git check-ref-format --branch @{-1}" bit a "BUG()" when run
   outside a repository for obvious reasons; clarify the documentation
   and make sure we do not even try to expand the at-mark magic in
   such a case, but still call the validation logic for branch names.

 * Command line completion (in contrib/) update.

 * Description of blame.{showroot,blankboundary,showemail,date}
   configuration variables have been added to "git config --help".

 * After an error from lstat(), diff_populate_filespec() function
   sometimes still went ahead and used invalid data in struct stat,
   which has been fixed.

 * UNC paths are also relevant in Cygwin builds and they are now
   tested just like Mingw builds.

 * Correct start-up sequence so that a repository could be placed
   immediately under the root directory again (which was broken at
   around Git 2.13).

 * The credential helper for libsecret (in contrib/) has been improved
   to allow possibly prompting the end user to unlock secrets that are
   currently locked (otherwise the secrets may not be loaded).

 * Updates from GfW project.

 * "git rebase -i" recently started misbehaving when a submodule that
   is configured with 'submodule.<name>.ignore' is dirty; this has
   been corrected.

 * Some error messages did not quote filenames shown in it, which have
   been fixed.

 * Building with NO_LIBPCRE1_JIT did not disable it, which has been fixed.

 * We used to add an empty alternate object database to the system
   that does not help anything; it has been corrected.

 * Error checking in "git imap-send" for empty response has been
   improved.

 * An ancient bug in "git apply --ignore-space-change" codepath has
   been fixed.

 * There was a recent semantic mismerge in the codepath to write out a
   section of a configuration section, which has been corrected.

Log message:
git: updated to 2.15.0

Git 2.15 Release Notes

Backward compatibility notes and other notable changes.

 * Use of an empty string as a pathspec element that is used for
   'everything matches' is still warned and Git asks users to use a
   more explicit '.' for that instead.  The hope is that existing
   users will not mind this change, and eventually the warning can be
   turned into a hard error, upgrading the deprecation into removal of
   this (mis)feature.  That is now scheduled to happen in Git v2.16,
   the next major release after this one.

 * Git now avoids blindly falling back to ".git" when the setup
   sequence said we are _not_ in Git repository.  A corner case that
   happens to work right now may be broken by a call to BUG().
   We've tried hard to locate such cases and fixed them, but there
   might still be cases that need to be addressed--bug reports are
   greatly appreciated.

 * "branch --set-upstream" that has been deprecated in Git 1.8 has
   finally been retired.

Updates since v2.14
-------------------

UI, Workflows & Features

 * An example that is now obsolete has been removed from a sample hook,
   and an old example in it that added a sign-off manually has been
   improved to use the interpret-trailers command.

 * The advice message given when "git rebase" stops for conflicting
   changes has been improved.

 * The "rerere-train" script (in contrib/) learned the \ 
"--overwrite"
   option to allow overwriting existing recorded resolutions.

 * "git contacts" (in contrib/) now lists the address on the
   "Reported-by:" trailer to its output, in addition to those on
   S-o-b: and other trailers, to make it easier to notify (and thank)
   the original bug reporter.

 * "git rebase", especially when it is run by mistake and ends up
   trying to replay many changes, spent long time in silence.  The
   command has been taught to show progress report when it spends
   long time preparing these many changes to replay (which would give
   the user a chance to abort with ^C).

 * "git merge" learned a "--signoff" option to add the \ 
Signed-off-by:
   trailer with the committer's name.

 * "git diff" learned to optionally paint new lines that are the same
   as deleted lines elsewhere differently from genuinely new lines.

 * "git interpret-trailers" learned to take the trailer specifications
   from the command line that overrides the configured values.

 * "git interpret-trailers" has been taught a "--parse" and a few
   other options to make it easier for scripts to grab existing
   trailer lines from a commit log message.

 * The "--format=%(trailers)" option "git log" and its \ 
friends take
   learned to take the 'unfold' and 'only' modifiers to normalize its
   output, e.g. "git log --format=%(trailers:only,unfold)".

 * "gitweb" shows a link to visit the 'raw' contents of blbos in the
   history overview page.

 * "[gc] rerereResolved = 5.days" used to be invalid, as the variable
   is defined to take an integer counting the number of days.  It now
   is allowed.

 * The code to acquire a lock on a reference (e.g. while accepting a
   push from a client) used to immediately fail when the reference is
   already locked---now it waits for a very short while and retries,
   which can make it succeed if the lock holder was holding it during
   a read-only operation.

 * "branch --set-upstream" that has been deprecated in Git 1.8 has
   finally been retired.

 * The codepath to call external process filter for smudge/clean
   operation learned to show the progress meter.

 * "git rev-parse" learned "--is-shallow-repository", that \ 
is to be
   used in a way similar to existing "--is-bare-repository" and
   friends.

 * "git describe --match <pattern>" has been taught to play well with
   the "--all" option.

 * "git branch" learned "-c/-C" to create a new branch by \ 
copying an
   existing one.

 * Some commands (most notably "git status") makes an opportunistic
   update when performing a read-only operation to help optimize later
   operations in the same repository.  The new "--no-optional-locks"
   option can be passed to Git to disable them.

 * "git for-each-ref --format=..." learned a new format element,
   %(trailers), to show only the commit log trailer part of the log
   message.

Performance, Internal Implementation, Development Support etc.

...more...

Log message:
git: updated to 2.14.3

Git v2.14.3 Release Notes

Fixes since v2.14.2

 * A helper function to read a single whole line into strbuf
   mistakenly triggered OOM error at EOF under certain conditions,
   which has been fixed.

 * In addition to "cc: <a@dd.re.ss> # cruft", "cc: \ 
a@dd.re.ss # cruft"
   was taught to "git send-email" as a valid way to tell it that it
   needs to also send a carbon copy to <a@dd.re.ss> in the trailer
   section.

 * Fix regression to "gitk --bisect" by a recent update.

 * Unlike "git commit-tree < file", "git commit-tree -F \ 
file" did not
   pass the contents of the file verbatim and instead completed an
   incomplete line at the end, if exists.  The latter has been updated
   to match the behaviour of the former.

 * "git archive", especially when used with pathspec, stored an empty
   directory in its output, even though Git itself never does so.
   This has been fixed.

 * API error-proofing which happens to also squelch warnings from GCC.

 * "git gc" tries to avoid running two instances at the same time by
   reading and writing pid/host from and to a lock file; it used to
   use an incorrect fscanf() format when reading, which has been
   corrected.

 * The test linter has been taught that we do not like "echo -e".

 * Code cmp.std.c nitpick.

 * "git describe --match" learned to take multiple patterns in v2.13
   series, but the feature ignored the patterns after the first one
   and did not work at all.  This has been fixed.

 * "git cat-file --textconv" started segfaulting recently, which
   has been corrected.

 * The built-in pattern to detect the "function header" for HTML did
   not match <H1>..<H6> elements without any attributes, which has
   been fixed.

 * "git mailinfo" was loose in decoding quoted printable and produced
   garbage when the two letters after the equal sign are not
   hexadecimal.  This has been fixed.

 * The documentation for '-X<option>' for merges was misleadingly
   written to suggest that "-s theirs" exists, which is not the case.

 * Spell the name of our system as "Git" in the output from
   request-pull script.

 * Fixes for a handful memory access issues identified by valgrind.

 * Backports a moral equivalent of 2015 fix to the poll emulation from
   the upstream gnulib to fix occasional breakages on HPE NonStop.

 * In the "--format=..." option of the "git for-each-ref" \ 
command (and
   its friends, i.e. the listing mode of "git branch/tag"), \ 
"%(atom:)"
   (e.g. "%(refname:)", "%(body:)" used to error out.  \ 
Instead, treat
   them as if the colon and an empty string that follows it were not
   there.

 * Users with "color.ui = always" in their configuration were broken
   by a recent change that made plumbing commands to pay attention to
   them as the patch created internally by "git add -p" were colored
   (heh) and made unusable.  This has been fixed.

 * "git branch -M a b" while on a branch that is completely unrelated
   to either branch a or branch b misbehaved when multiple worktree
   was in use.  This has been fixed.

 * "git fast-export" with -M/-C option issued "copy" \ 
instruction on a
   path that is simultaneously modified, which was incorrect.

 * The checkpoint command "git fast-import" did not flush updates to
   refs and marks unless at least one object was created since the
   last checkpoint, which has been corrected, as these things can
   happen without any new object getting created.

 * The scripts to drive TravisCI has been reorganized and then an
   optimization to avoid spending cycles on a branch whose tip is
   tagged has been implemented.

 * "git fetch <there> <src>:<dst>" allows an object \ 
name on the <src>
   side when the other side accepts such a request since Git v2.5, but
   the documentation was left stale.

 * A regression in 2.11 that made the code to read the list of
   alternate object stores overrun the end of the string has been
   fixed.

Also contains various documentation updates and code clean-ups.

Log message:
git: update to 2.14.2

Fixes since v2.14.1

 * Because recent Git for Windows do come with a real msgfmt, the
   build procedure for git-gui has been updated to use it instead of a
   hand-rolled substitute.

 * "%C(color name)" in the pretty print format always produced ANSI
   color escape codes, which was an early design mistake.  They now
   honor the configuration (e.g. "color.ui = never") and also tty-ness
   of the output medium.

 * The http.{sslkey,sslCert} configuration variables are to be
   interpreted as a pathname that honors "~[username]/" prefix, but
   weren't, which has been fixed.

 * Numerous bugs in walking of reflogs via "log -g" and friends have
   been fixed.

 * "git commit" when seeing an totally empty message said "you did not
   edit the message", which is clearly wrong.  The message has been
   corrected.

 * When a directory is not readable, "gitweb" fails to build the
   project list.  Work this around by skipping such a directory.

 * A recently added test for the "credential-cache" helper revealed
   that EOF detection done around the time the connection to the cache
   daemon is torn down were flaky.  This was fixed by reacting to
   ECONNRESET and behaving as if we got an EOF.

 * Some versions of GnuPG fail to kill gpg-agent it auto-spawned
   and such a left-over agent can interfere with a test.  Work it
   around by attempting to kill one before starting a new test.

 * "git log --tag=no-such-tag" showed log starting from HEAD, which
   has been fixed---it now shows nothing.

 * The "tag.pager" configuration variable was useless for those who
   actually create tag objects, as it interfered with the use of an
   editor.  A new mechanism has been introduced for commands to enable
   pager depending on what operation is being carried out to fix this,
   and then "git tag -l" is made to run pager by default.

 * "git push --recurse-submodules $there HEAD:$target" was not
   propagated down to the submodules, but now it is.

 * Commands like "git rebase" accepted the --rerere-autoupdate option
   from the command line, but did not always use it.  This has been
   fixed.

 * "git clone --recurse-submodules --quiet" did not pass the quiet
   option down to submodules.

 * "git am -s" has been taught that some input may end with a trailer
   block that is not Signed-off-by: and it should refrain from adding
   an extra blank line before adding a new sign-off in such a case.

 * "git svn" used with "--localtime" option did not compute \ 
the tz
   offset for the timestamp in question and instead always used the
   current time, which has been corrected.

 * Memory leaks in a few error codepaths have been plugged.

 * bash 4.4 or newer gave a warning on NUL byte in command
   substitution done in "git stash"; this has been squelched.

 * "git grep -L" and "git grep --quiet -L" reported \ 
different exit
   codes; this has been corrected.

 * When handshake with a subprocess filter notices that the process
   asked for an unknown capability, Git did not report what program
   the offending subprocess was running.  This has been corrected.

 * "git apply" that is used as a better "patch -p1" failed \ 
to apply a
   taken from a file with CRLF line endings to a file with CRLF line
   endings.  The root cause was because it misused convert_to_git()
   that tried to do "safe-crlf" processing by looking at the index
   entry at the same path, which is a nonsense---in that mode, "apply"
   is not working on the data in (or derived from) the index at all.
   This has been fixed.

 * Killing "git merge --edit" before the editor returns control left
   the repository in a state with MERGE_MSG but without MERGE_HEAD,
   which incorrectly tells the subsequent "git commit" that there was
   a squash merge in progress.  This has been fixed.

 * "git archive" did not work well with pathspecs and the
   export-ignore attribute.

 * "git cvsserver" no longer is invoked by "git daemon" by \ 
default,
   as it is old and largely unmaintained.

 * Various Perl scripts did not use safe_pipe_capture() instead of
   backticks, leaving them susceptible to end-user input.  They have
   been corrected.

Log message:
Follow some http redirects.

Log message:
Git v2.14.1:
This release forward-ports the fix for "ssh://..." URL from Git v2.7.6

Log message:
Git 2.14 Release Notes
======================

Backward compatibility notes and other notable changes.

 * Use of an empty string as a pathspec element that is used for
   'everything matches' is still warned and Git asks users to use a
   more explicit '.' for that instead.  The hope is that existing
   users will not mind this change, and eventually the warning can be
   turned into a hard error, upgrading the deprecation into removal of
   this (mis)feature.  That is not scheduled to happen in the upcoming
   release (yet).

 * Git now avoids blindly falling back to ".git" when the setup
   sequence said we are _not_ in Git repository.  A corner case that
   happens to work right now may be broken by a call to die("BUG").
   We've tried hard to locate such cases and fixed them, but there
   might still be cases that need to be addressed--bug reports are
   greatly appreciated.

 * The experiment to improve the hunk-boundary selection of textual
   diff output has finished, and the "indent heuristics" has now
   become the default.

 * Git can now be built with PCRE v2 instead of v1 of the PCRE
   library. Replace USE_LIBPCRE=YesPlease with USE_LIBPCRE2=YesPlease
   in existing build scripts to build against the new version.  As the
   upstream PCRE maintainer has abandoned v1 maintenance for all but
   the most critical bug fixes, use of v2 is recommended.

Updates since v2.13
-------------------

UI, Workflows & Features

 * The colors in which "git status --short --branch" showed the names
   of the current branch and its remote-tracking branch are now
   configurable.

 * "git clone" learned the "--no-tags" option not to fetch \ 
all tags
   initially, and also set up the tagopt not to follow any tags in
   subsequent fetches.

 * "git archive --format=zip" learned to use zip64 extension when
   necessary to go beyond the 4GB limit.

 * "git reset" learned "--recurse-submodules" option.

 * "git diff --submodule=diff" now recurses into nested submodules.

 * "git repack" learned to accept the --threads=<n> option and \ 
pass it
   to pack-objects.

 * "git send-email" learned to run sendemail-validate hook to inspect
   and reject a message before sending it out.

 * There is no good reason why "git fetch $there $sha1" should fail
   when the $sha1 names an object at the tip of an advertised ref,
   even when the other side hasn't enabled allowTipSHA1InWant.

 * The "[includeIf "gitdir:$dir"] path=..." mechanism \ 
introduced in
   2.13.0 would canonicalize the path of the gitdir being matched,
   and did not match e.g. "gitdir:~/work/*" against a repo in
   "~/work/main" if "~/work" was a symlink to \ 
"/mnt/storage/work".
   Now we match both the resolved canonical path and what "pwd" would
   show. The include will happen if either one matches.

 * The "indent" heuristics is now the default in "diff". The
   diff.indentHeuristic configuration variable can be set to "false"
   for those who do not want it.

 * Many commands learned to pay attention to submodule.recurse
   configuration.

 * The convention for a command line is to follow "git cmdname
   --options" with revisions followed by an optional "--"
   disambiguator and then finally pathspecs.  When "--" is not there,
   we make sure early ones are all interpretable as revs (and do not
   look like paths) and later ones are the other way around.  A
   pathspec with "magic" (e.g. ":/p/a/t/h" that matches \ 
p/a/t/h from
   the top-level of the working tree, no matter what subdirectory you
   are working from) are conservatively judged as "not a path", which
   required disambiguation more often.  The command line parser
   learned to say "it's a pathspec" a bit more often when the syntax
   looks like so.

 * Update "perl-compatible regular expression" support to enable JIT
   and also allow linking with the newer PCRE v2 library.

 * "filter-branch" learned a pseudo filter "--setup" that \ 
can be used
   to define common functions/variables that can be used by other
   filters.

 * Using "git add d/i/r" when d/i/r is the top of the working tree of
   a separate repository would create a gitlink in the index, which
   would appear as a not-quite-initialized submodule to others.  We
   learned to give warnings when this happens.

 * "git status" learned to optionally give how many stash entries there
   are in its output.

 * "git status" has long shown essentially the same message as "git
   commit"; the message it gives while preparing for the root commit,
   i.e. "Initial commit", was hard to understand for some new users.
   Now it says "No commits yet" to stress more on the current status
   (rather than the commit the user is preparing for, which is more in
   line with the focus of "git commit").

 * "git send-email" now has --batch-size and --relogin-delay options
    which can be used to overcome limitations on SMTP servers that
    restrict on how many of e-mails can be sent in a single session.

 * An old message shown in the commit log template was removed, as it
   has outlived its usefulness.

 * "git pull --rebase --recurse-submodules" learns to rebase the
   branch in the submodules to an updated base.

 * "git log" learned -P as a synonym for --perl-regexp, "git \ 
grep"
   already had such a synonym.

 * "git log" didn't understand --regexp-ignore-case when combined with
   --perl-regexp. This has been fixed.

Performance, Internal Implementation, Development Support etc.

 * The default packed-git limit value has been raised on larger
   platforms to save "git fetch" from a (recoverable) failure while
   "gc" is running in parallel.

 * Code to update the cache-tree has been tightened so that we won't
   accidentally write out any 0{40} entry in the tree object.

 * Attempt to allow us notice "fishy" situation where we fail to
   remove the temporary directory used during the test.

 * Travis CI gained a task to format the documentation with both
   AsciiDoc and AsciiDoctor.

 * Some platforms have ulong that is smaller than time_t, and our
   historical use of ulong for timestamp would mean they cannot
   represent some timestamp that the platform allows.  Invent a
   separate and dedicated timestamp_t (so that we can distingiuish
   timestamps and a vanilla ulongs, which along is already a good
   move), and then declare uintmax_t is the type to be used as the
   timestamp_t.

 * We can trigger Windows auto-build tester (credits: Dscho &
   Microsoft) from our existing Travis CI tester now.

 * Conversion from uchar[20] to struct object_id continues.

 * Simplify parse_pathspec() codepath and stop it from looking at the
   default in-core index.

 * Add perf-test for wildmatch.

 * Code from "conversion using external process" codepath has been
   extracted to a separate sub-process.[ch] module.

 * When "git checkout", "git merge", etc. manipulates the in-core
   index, various pieces of information in the index extensions are
   discarded from the original state, as it is usually not the case
   that they are kept up-to-date and in-sync with the operation on the
   main index.  The untracked cache extension is copied across these
   operations now, which would speed up "git status" (as long as the
   cache is properly invalidated).

 * The internal implementation of "git grep" has seen some clean-up.

 * Update the C style recommendation for notes for translators, as
   recent versions of gettext tools can work with our style of
   multi-line comments.

 * The implementation of "ref" API around the "packed refs" \ 
have been
   cleaned up, in preparation for further changes.

 * The internal logic used in "git blame" has been libified to make it
   easier to use by cgit.

 * Our code often opens a path to an optional file, to work on its
   contents when we can successfully open it.  We can ignore a failure
   to open if such an optional file does not exist, but we do want to
   report a failure in opening for other reasons (e.g. we got an I/O
   error, or the file is there, but we lack the permission to open).

   The exact errors we need to ignore are ENOENT (obviously) and
   ENOTDIR (less obvious).  Instead of repeating comparison of errno
   with these two constants, introduce a helper function to do so.

 * We often try to open a file for reading whose existence is
   optional, and silently ignore errors from open/fopen; report such
   errors if they are not due to missing files.

 * When an existing repository is used for t/perf testing, we first
   create bit-for-bit copy of it, which may grab a transient state of
   the repository and freeze it into the repository used for testing,
   which then may cause Git operations to fail.  Single out "the index
   being locked" case and forcibly drop the lock from the copy.

 * Three instances of the same helper function have been consolidated
   to one.

 * "fast-import" uses a default pack chain depth that is consistent
   with other parts of the system.

 * A new test to show the interaction between the pattern [^a-z]
   (which matches '/') and a slash in a path has been added.  The
   pattern should not match the slash with "pathmatch", but should
   with "wildmatch".

 * The 'diff-highlight' program (in contrib/) has been restructured
   for easier reuse by an external project 'diff-so-fancy'.

 * A common pattern to free a piece of memory and assign NULL to the
   pointer that used to point at it has been replaced with a new
   FREE_AND_NULL() macro.

 * Traditionally, the default die() routine had a code to prevent it
   from getting called multiple times, which interacted badly when a
   threaded program used it (one downside is that the real error may
   be hidden and instead the only error message given to the user may
   end up being "die recursion detected", which is not very useful).

 * Introduce a "repository" object to eventually make it easier to
   work in multiple repositories (the primary focus is to work with
   the superproject and its submodules) in a single process.

 * Optimize "what are the object names already taken in an alternate
   object database?" query that is used to derive the length of prefix
   an object name is uniquely abbreviated to.

 * The hashmap API has been updated so that data to customize the
   behaviour of the comparison function can be specified at the time a
   hashmap is initialized.

 * The "collision detecting" SHA-1 implementation shipped with 2.13 is
   now integrated into git.git as a submodule (the first submodule to
   ship with git.git). Clone git.git with --recurse-submodules to get
   it. For now a non-submodule copy of the same code is also shipped
   as part of the tree.

 * A recent update made it easier to use "-fsanitize=" option while
   compiling but supported only one sanitize option.  Allow more than
   one to be combined, joined with a comma, like "make SANITIZE=foo,bar".

 * Use "p4 -G" to make "p4 changes" output more Python-friendly
   to parse.

 * We started using "%" PRItime, imitating "%" PRIuMAX and \ 
friends, as
   a way to format the internal timestamp value, but this does not
   play well with gettext(1) i18n framework, and causes "make pot"
   that is run by the l10n coordinator to create a broken po/git.pot
   file.  This is a possible workaround for that problem.

 * It turns out that Cygwin also needs the fopen() wrapper that
   returns failure when a directory is opened for reading.

Log message:
Git v2.13.4:

* Update the character width tables.

* A recent update broke an alias that contained an uppercase letter,
  which has been fixed.

* On Cygwin, similar to Windows, "git push //server/share/repository"
  ought to mean a repository on a network share that can be accessed
  locally, but this did not work correctly due to stripping the double
  slashes at the beginning.

* The progress meter did not give a useful output when we haven't had
  0.5 seconds to measure the throughput during the interval.  Instead
  show the overall throughput rate at the end, which is a much more
  useful number.

* We run an early part of "git gc" that deals with refs before
  daemonising (and not under lock) even when running a background
  auto-gc, which caused multiple gc processes attempting to run the
  early part at the same time.  This is now prevented by running the
  early part also under the GC lock.