Optimize code that handles large number of refs in the "git fetch"
code path.

* ps/fetch-optim:
  fetch: avoid second connectivity check if we already have all objects
  fetch: merge fetching and consuming refs
  fetch: refactor fetch refs to be more extendable
  fetch-pack: optimize loading of refs via commit graph
  connected: refactor iterator to return next object ID directly
  fetch: avoid unpacking headers in object existence check
  fetch: speed up lookup of want refs via commit-graph

The reachability bitmap file used to be generated only for a single
pack, but now we've learned to generate bitmaps for history that
span across multiple packfiles.

* tb/multi-pack-bitmaps: (27 commits)
  p5326: perf tests for MIDX bitmaps
  p5310: extract full and partial bitmap tests
  midx: respect 'GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP'
  t7700: update to work with MIDX bitmap test knob
  t5319: don't write MIDX bitmaps in t5319
  t5310: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP
  t0410: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP
  t5326: test multi-pack bitmap behavior
  t/helper/test-read-midx.c: add --checksum mode
  t5310: move some tests to lib-bitmap.sh
  pack-bitmap: write multi-pack bitmaps
  pack-bitmap: read multi-pack bitmaps
  pack-bitmap.c: avoid redundant calls to try_partial_reuse
  pack-bitmap.c: introduce 'bitmap_is_preferred_refname()'
  pack-bitmap.c: introduce 'nth_bitmap_object_oid()'
  pack-bitmap.c: introduce 'bitmap_num_objects()'
  midx: avoid opening multiple MIDXs when writing
  midx: close linked MIDXs, avoid leaking memory
  midx: infer preferred pack when not given one
  midx: reject empty `--preferred-pack`'s
  ...

Recent "diff -m" changes broke "gitk", which has been corrected.

* so/diff-index-regression-fix:
  diff-index: restore -c/--cc options handling

Regression fix.

* ab/send-email-config-fix:
  send-email: fix a "first config key wins" regression in v2.33.0

Build simplification.

* ab/no-more-check-bindir:
  Makefile: remove the check_bindir script

Docfix.

* bs/doc-bugreport-outdir:
  Documentation: fix default directory of git bugreport -o

Tie-break branches that point at the same object in the list of
branches on GitWeb to show the one pointed at by HEAD early.

* gh/gitweb-branch-sort:
  gitweb: use HEAD as secondary sort key in git_get_heads_list()

The code to make "git grep" recurse into submodules has been
updated to migrate away from the "add submodule's object store as
an alternate object store" mechanism (which is suboptimal).

* jt/grep-wo-submodule-odb-as-alternate:
  t7814: show lack of alternate ODB-adding
  submodule-config: pass repo upon blob config read
  grep: add repository to OID grep sources
  grep: allocate subrepos on heap
  grep: read submodule entry with explicit repo
  grep: typesafe versions of grep_source_init
  grep: use submodule-ODB-as-alternate lazy-addition
  submodule: lazily add submodule ODBs as alternates

The "git apply -3" code path learned not to bother the lower level
merge machinery when the three-way merge can be trivially resolved
without the content level merge.

* jc/trivial-threeway-binary-merge:
  apply: resolve trivial merge without hitting ll-merge with "--3way"

CI update.

* cb/ci-build-pedantic:
  ci: run a pedantic build as part of the GitHub workflow

The logic for auto-correction of misspelt subcommands learned to go
interactive when the help.autocorrect configuration variable is set
to 'prompt'.

* ab/help-autocorrect-prompt:
  help.c: help.autocorrect=prompt waits for user action

Teach "test_pause" and "debug" helpers to allow using the HOME and
TERM environment variables the user usually uses.

* pb/test-use-user-env:
  test-lib-functions: keep user's debugger config files and TERM in 'debug'
  test-lib-functions: optionally keep HOME, TERM and SHELL in 'test_pause'
  test-lib-functions: use 'TEST_SHELL_PATH' in 'test_pause'

"make INSTALL_STRIP=-s install" allows the installation step to use
"install -s" to strip the binaries as they get installed.

* bs/install-strip:
  make: add INSTALL_STRIP option variable

The code that optionally creates the *.rev reverse index file has
been optimized to avoid needless computation when it is not writing
the file out.

* ab/reverse-midx-optim:
  pack-write: skip *.rev work when not writing *.rev

The tracing of process ancestry information has been enhanced.

* ab/tr2-leaks-and-fixes:
  tr2: log N parent process names on Linux
  tr2: do compiler enum check in trace2_collect_process_info()
  tr2: leave the parent list empty upon failure & don't leak memory
  tr2: stop leaking "thread_name" memory
  tr2: clarify TRACE2_PROCESS_INFO_EXIT comment under Linux
  tr2: remove NEEDSWORK comment for "non-procfs" implementations

"git maintenance" scheduler learned to use systemd timers as a
possible backend.

* lh/systemd-timers:
  maintenance: add support for systemd timers on Linux
  maintenance: `git maintenance run` learned `--scheduler=<scheduler>`
  cache.h: Introduce a generic "xdg_config_home_for(…)" function

Reduce number of write(2) system calls while sending the
ref advertisement.

* jv/pkt-line-batch:
  upload-pack: use stdio in send_ref callbacks
  pkt-line: add stdio packet write functions

"git diff --submodule=diff" showed failure from run_command() when
trying to run diff inside a submodule, when the user manually
removes the submodule directory.

* dt/submodule-diff-fixes:
  diff --submodule=diff: don't print failure message twice
  diff --submodule=diff: do not fail on ever-initialied deleted submodules
  t4060: remove unused variable

The code to show progress indicator in a few codepaths did not
cover between 0-100%, which has been corrected.

* ab/progress-users-adjust-counters:
  entry: show finer-grained counter in "Filtering content" progress line
  commit-graph: fix bogus counter in "Scanning merged commits" progress line

"git update-ref --stdin" failed to flush its output as needed,
which potentially led the conversation to a deadlock.

* ps/update-ref-batch-flush:
  update-ref: fix streaming of status updates

Update the build procedure to use the "-pedantic" build when
DEVELOPER makefile macro is in effect.

* cb/pedantic-build-for-developers:
  developer: enable pedantic by default
  win32: allow building with pedantic mode enabled
  gettext: remove optional non-standard parens in N_() definition

"git range-diff -I... <range> <range>" segfaulted, which has been
corrected.

* rs/range-diff-avoid-segfault-with-I:
  range-diff: avoid segfault with -I

Leakfix.

* jc/prefix-filename-allocates:
  hash-object: prefix_filename() returns allocated memory these days

The "--preserve-merges" option of "git rebase" has been removed.

* js/retire-preserve-merges:
  sequencer: restrict scope of a formerly public function
  rebase: remove a no-longer-used function
  rebase: stop mentioning the -p option in comments
  rebase: remove obsolete code comment
  rebase: drop the internal `rebase--interactive` command
  git-svn: drop support for `--preserve-merges`
  rebase: drop support for `--preserve-merges`
  pull: remove support for `--rebase=preserve`
  tests: stop testing `git rebase --preserve-merges`
  remote: warn about unhandled branch.<name>.rebase values
  t5520: do not use `pull.rebase=preserve`

The order in which various files that make up a single (conceptual)
packfile has been reevaluated and straightened up.  This matters in
correctness, as an incomplete set of files must not be shown to a
running Git.

* tb/pack-finalize-ordering:
  pack-objects: rename .idx files into place after .bitmap files
  pack-write: split up finish_tmp_packfile() function
  builtin/index-pack.c: move `.idx` files into place last
  index-pack: refactor renaming in final()
  builtin/repack.c: move `.idx` files into place last
  pack-write.c: rename `.idx` files after `*.rev`
  pack-write: refactor renaming in finish_tmp_packfile()
  bulk-checkin.c: store checksum directly
  pack.h: line-wrap the definition of finish_tmp_packfile()

The reachability bitmap file used to be generated only for a single
pack, but now we've learned to generate bitmaps for history that
span across multiple packfiles.

* tb/multi-pack-bitmaps:
  pack-bitmap: drop bitmap_index argument from try_partial_reuse()
  pack-bitmap: drop repository argument from prepare_midx_bitmap_git()

This reverts commit eed4e81, reversing
changes made to 348fe07, so that we
can eventually replace it with a newer iteration.  As it stands, the
topic just makes it segfault when used with OpenSSH 8.7 (the latest).

Add progress display to "git bundle unbundle".

* ab/unbundle-progress:
  bundle: show progress on "unbundle"
  index-pack: add --progress-title option
  bundle API: change "flags" to be "extra_index_pack_args"
  bundle API: start writing API documentation

The command line complation for "git send-email" options have been
tweaked to make it easier to keep it in sync with the command itself.

* tp/send-email-completion:
  send-email docs: add format-patch options
  send-email: programmatically generate bash completions

Leakfix.

* tb/plug-pack-bitmap-leaks:
  pack-bitmap.c: more aggressively free in free_bitmap_index()
  pack-bitmap.c: don't leak type-level bitmaps
  midx.c: write MIDX filenames to strbuf
  builtin/multi-pack-index.c: don't leak concatenated options
  builtin/repack.c: avoid leaking child arguments
  builtin/pack-objects.c: don't leak memory via arguments
  t/helper/test-read-midx.c: free MIDX within read_midx_file()
  midx.c: don't leak MIDX from verify_midx_file
  midx.c: clean up chunkfile after reading the MIDX

Code simplification.

* rd/http-backend-code-simplification:
  http-backend: remove a duplicated code branch

"git add", "git mv", and "git rm" have been adjusted to avoid
updating paths outside of the sparse-checkout definition unless
the user specifies a "--sparse" option.

* ds/add-rm-with-sparse-index:
  dir: fix directory-matching bug

Various bugs in "git rebase -r" have been fixed.

* pw/rebase-r-fixes:
  rebase -i: fix rewording with --committer-date-is-author-date

Git 2.34-rc1

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# gpg: Signature made Wed 03 Nov 2021 01:39:28 PM PDT
# gpg:                using RSA key E1F036B1FEE7221FC778ECEFB0B5E88696AFE6CB
# gpg: Good signature from "Junio C Hamano <[email protected]>" [ultimate]
# gpg:                 aka "Junio C Hamano <[email protected]>" [ultimate]
# gpg:                 aka "Junio C Hamano <[email protected]>" [ultimate]

* tag 'v2.34.0-rc1':
  Git 2.34-rc1

* vd/pthread-setspecific-g11-fix:
  async_die_is_recursing: work around GCC v11.x issue on Fedora

Make a few helper functions unused and then lose them.

* ab/sh-retire-helper-functions:
  git-sh-setup: remove "sane_grep", it's not needed anymore
  git-sh-setup: remove unused sane_egrep() function
  git-instaweb: unconditionally assume that gitweb is mod_perl capable
  Makefile: remove $(NO_CURL) from $(SCRIPT_DEFINES)
  Makefile: remove $(GIT_VERSION) from $(SCRIPT_DEFINES)
  Makefile: move git-SCRIPT-DEFINES adjacent to $(SCRIPT_DEFINES)

The clean/smudge conversion code path has been prepared to better
work on platforms where ulong is narrower than size_t.

* mc/clean-smudge-with-llp64:
  clean/smudge: allow clean filters to process extremely large files
  odb: guard against data loss checking out a huge file
  git-compat-util: introduce more size_t helpers
  odb: teach read_blob_entry to use size_t
  t1051: introduce a smudge filter test for extremely large files
  test-lib: add prerequisite for 64-bit platforms
  test-tool genzeros: generate large amounts of data more efficiently
  test-genzeros: allow more than 2G zeros in Windows

Fix ssh-signing test to work on a platform where the default ACL is
overly loose to upset OpenSSH (reported on an installation of Cygwin).

* ad/ssh-signing-testfix:
  t/lib-git.sh: fix ACL-related permissions failure

Random changes to parse-options implementation.

* ab/parse-options-cleanup:
  parse-options.[ch]: revert use of "enum" for parse_options()

* ds/no-usable-cron-on-macos:
  maintenance: disable cron on macOS

* js/simple-ipc-cygwin-socket-fix:
  simple-ipc: work around issues with Cygwin's Unix socket emulation

* jk/ssh-signing-fix:
  t/lib-gpg: avoid broken versions of ssh-keygen

The revision traversal API has been optimized by taking advantage
of the commit-graph, when available, to determine if a commit is
reachable from any of the existing refs.

* ps/connectivity-optim:
  Revert "connected: do not sort input revisions"

"git fsck" has been taught to report mismatch between expected and
actual types of an object better.

* ab/fsck-unexpected-type:
  object-file: free(*contents) only in read_loose_object() caller
  object-file: fix SEGV on free() regression in v2.34.0-rc2

* js/trace2-raise-format-version:
  trace2: increment event format version

"git grep" looking in a blob that has non-UTF8 payload was
completely broken when linked with certain versions of PCREv2
library in the latest release.

* hm/paint-hits-in-log-grep:
  Revert "grep/pcre2: fix an edge case concerning ascii patterns and UTF-8 data"

"git pull" with any strategy when the other side is behind us
should succeed as it is a no-op, but doesn't.

* ev/pull-already-up-to-date-is-noop:
  pull: should be noop when already-up-to-date

Doc fix.

* ab/update-submitting-patches:
  SubmittingPatches: fix Asciidoc syntax in "GitHub CI" section

* master:
  0th batch for early fixes