In ed32b788 (version --build-options: report commit, too, if
possible, 2017-12-15), we introduced code to let `git version
--build-options` report the current commit from which the binaries were
built, if any.

To prevent erroneous commits from being reported (e.g. when unpacking
Git's source code from a .tar.gz file into a subdirectory of a different
Git project, as e.g. git_osx_installer does), we painstakingly set
GIT_CEILING_DIRECTORIES when trying to determine the current commit.

Except that we got the quoting wrong, and that variable therefore does
not have the desired effect.

The issue is that the $(shell) is resolved before the output is stuffed
into the command-line with -DGIT_BUILT_FROM_COMMIT, and therefore is
*not* inside quotes. And thus backslashing the quotes is wrong, as the
quote gets literally inserted into the CEILING_DIRECTORIES variable.

Let's fix that quoting, and while at it, also suppress the unhelpful
message

fatal: not a git repository (or any of the parent directories): .git

that gets printed to stderr if no current commit could be determined,
and might scare the occasional developer who simply tries to build Git
from scratch.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Helped-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In particular when local tags are used (or tags that are pushed to some
fork) to build Git, it is very hard to figure out from which particular
revision a particular Git executable was built. It gets worse when those
tags are deleted, or even updated.

Let's just report an exact, unabbreviated commit name in our build
options.

We need to be careful, though, to report when the current commit cannot
be determined, e.g. when building from a tarball without any associated
Git repository. This could be the case also when extracting Git's source
code into an unrelated Git worktree.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It can be helpful for bug reports to include information about the
environment in which the bug occurs. "git version --build-options" can
help to supplement this information. In addition to the size of 'long'
already reported by --build-options, also report the host's CPU type.
Example output:

   $ git version --build-options
   git version 2.9.3.windows.2.826.g06c0f2f
   cpu: x86_64
   sizeof-long: 4

New Makefile variable HOST_CPU supports cross-compiling.
Suggested-by: NAdric Norris <landstander668@gmail.com>
Signed-off-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NTodd Zullinger <tmz@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Code comment update.

* js/hashmap-update-sample:
  hashmap: adjust documentation to reflect reality

An internal function that was left for backward compatibility has
been removed, as there is no remaining callers.

* en/remove-stripspace:
  strbuf: remove unused stripspace function alias

Doc update for a feature available in Git v2.14 and upwards.

* jk/no-optional-locks:
  git-status.txt: mention --no-optional-locks

The code to iterate over loose object files got optimized.

* ds/for-each-file-in-obj-micro-optim:
  sha1_file: use strbuf_add() instead of strbuf_addf()

A regression in the progress eye-candy was fixed.

* jk/progress-delay-fix:
  progress: drop delay-threshold code
  progress: set default delay threshold to 100%, not 0%

@{-N} in "git checkout @{-N}" may refer to a detached HEAD state,
but the documentation was not clear about it, which has been fixed.

* ks/doc-checkout-previous:
  Doc/checkout: checking out using @{-N} can lead to detached state

"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.

* fk/sendmail-from-path:
  git-send-email: honor $PATH for sendmail binary

Developer doc updates.

* tg/t-readme-updates:
  t/README: document test_cmp_rev
  t/README: remove mention of adding copyright notices

A message fix.

* pc/submodule-helper:
  submodule--helper.c: i18n: add a missing space in message

Doc update.

* jc/receive-pack-hook-doc:
  hooks doc: clarify when receive-pack invokes its hooks

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

* ab/pcre2-grep:
  grep: fix segfault under -P + PCRE2 <=10.30 + (*NO_JIT)
  test-lib: add LIBPCRE1 & LIBPCRE2 prerequisites

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>.

* ra/decorate-limit-refs:
  log: add option to choose which refs to decorate

An infrastructure to define what hash function is used in Git is
introduced, and an effort to plumb that throughout various
codepaths has been started.

* bc/hash-algo:
  repository: fix a sparse 'using integer as NULL pointer' warning
  Switch empty tree and blob lookups to use hash abstraction
  Integrate hash algorithm support with repo setup
  Add structure representing hash algorithm
  setup: expose enumerated repo info

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The ssh-variant 'simple' introduced earlier broke existing
installations by not passing --port/-4/-6 and not diagnosing an
attempt to pass these as an error.  Instead, default to
automatically detect how compatible the GIT_SSH/GIT_SSH_COMMAND is
to OpenSSH convention and then error out an invocation to make it
easier to diagnose connection errors.

* jn/ssh-wrappers:
  connect: correct style of C-style comment
  ssh: 'simple' variant does not support --port
  ssh: 'simple' variant does not support -4/-6
  ssh: 'auto' variant to select between 'ssh' and 'simple'
  connect: split ssh option computation to its own function
  connect: split ssh command line options into separate function
  connect: split git:// setup into a separate function
  connect: move no_fork fallback to git_tcp_connect
  ssh test: make copy_ssh_wrapper_as clean up after itself

A new mechanism to upgrade the wire protocol in place is proposed
and demonstrated that it works with the older versions of Git
without harming them.

* bw/protocol-v1:
  Documentation: document Extra Parameters
  ssh: introduce a 'simple' ssh variant
  i5700: add interop test for protocol transition
  http: tell server that the client understands v1
  connect: tell server that the client understands v1
  connect: teach client to recognize v1 server response
  upload-pack, receive-pack: introduce protocol version 1
  daemon: recognize hidden request arguments
  protocol: introduce protocol extension mechanisms
  pkt-line: add packet_write function
  connect: in ref advertisement, shallows are last

Doc update.

* sp/doc-info-attributes:
  doc: Mention info/attributes in gitrepository-layout

In addition to "git stash -m message", the command learned to
accept "git stash -mmessage" form.

* ph/stash-save-m-option-fix:
  stash: learn to parse -m/--message like commit does

Internaly we use 0{40} as a placeholder object name to signal the
codepath that there is no such object (e.g. the fast-forward check
while "git fetch" stores a new remote-tracking ref says "we know
there is no 'old' thing pointed at by the ref, as we are creating
it anew" by passing 0{40} for the 'old' side), and expect that a
codepath to locate an in-core object to return NULL as a sign that
the object does not exist.  A look-up for an object that does not
exist however is quite costly with a repository with large number
of packfiles.  This access pattern has been optimized.

* jk/fewer-pack-rescan:
  sha1_file: fast-path null sha1 as a missing object
  everything_local: use "quick" object existence check
  p5551: add a script to test fetch pack-dir rescans
  t/perf/lib-pack: use fast-import checkpoint to create packs
  p5550: factor out nonsense-pack creation

Doc update.

* tg/deprecate-stash-save:
  doc: prefer 'stash push' over 'stash save'

Doc update.

* rd/doc-notes-prune-fix:
  notes: correct 'git notes prune' options to '[-n] [-v]'

Doc update.

* rd/man-reflog-add-n:
  doc: add missing "-n" (dry-run) option to reflog man page

Doc update.

* rd/man-prune-progress:
  prune: add "--progress" to man page and usage msg

Further test clean-up.

* jt/submodule-tests-cleanup:
  Tests: clean up submodule recursive helpers

The build procedure has been taught to avoid some unnecessary
instability in the build products.

* jn/reproducible-build:
  generate-cmdlist: avoid non-deterministic output
  git-gui: sort entries in optimized tclIndex

Code clean-up.

* cc/git-packet-pm:
  Git/Packet.pm: use 'if' instead of 'unless'
  Git/Packet: clarify that packet_required_key_val_read allows EOF

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

* ac/complete-pull-autostash:
  completion: add --autostash and --no-autostash to pull

"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.

* hm/config-parse-expiry-date:
  config: add --expiry-date

"git branch --set-upstream" has been deprecated and (sort of)
removed, as "--set-upstream-to" is the preferred one these days.
The documentation still had "--set-upstream" listed on its
synopsys section, which has been corrected.

* tz/branch-doc-remove-set-upstream:
  branch doc: remove --set-upstream from synopsis

* cc/perf-run-config:
  perf: store subsection results in "test-results/$GIT_PERF_SUBSECTION/"
  perf/run: show name of rev being built
  perf/run: add run_subsection()
  perf/run: update get_var_from_env_or_config() for subsections
  perf/run: add get_subsections()
  perf/run: add calls to get_var_from_env_or_config()
  perf/run: add GIT_PERF_DIRS_OR_REVS
  perf/run: add get_var_from_env_or_config()
  perf/run: add '--config' option to the 'run' script

"git checkout --recursive" may overwrite and rewind the history of
the branch that happens to be checked out in submodule
repositories, which might not be desirable.  Detach the HEAD but
still allow the recursive checkout to succeed in such a case.

* sb/submodule-recursive-checkout-detach-head:
  Documentation/checkout: clarify submodule HEADs to be detached
  recursive submodules: detach HEAD from new state

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Clarify and enhance documentation for "merge-base --fork-point", as
it was clear what it computed but not why/what for.

* jc/merge-base-fork-point-doc:
  merge-base --fork-point doc: clarify the example and failure modes

A few scripts (both in production and tests) incorrectly redirected
their error output.  These have been corrected.

* tz/redirect-fix:
  rebase: fix stderr redirect in apply_autostash()
  t/lib-gpg: fix gpgconf stderr redirect to /dev/null