Reduce dependency on `the_repository` in add-patch.c file.

* sp/add-patch-with-fewer-the-repository:
  add-patch: use repository instance from add_i_state instead of the_repository

The way the "git log -L<range>:<file>" feature is bolted onto the
log/diff machinery is being reworked a bit to make the feature
compatible with more diff options, like -S/G.

* mm/line-log-use-standard-diff-output:
  doc: note that -L supports patch formatting and pickaxe options
  t4211: add tests for -L with standard diff options
  line-log: route -L output through the standard diff pipeline
  line-log: fix crash when combined with pickaxe options

Handling of signed commits and tags in fast-import has been made more
configurable.

* jt/fast-import-signed-modes:
  fast-import: add 'abort-if-invalid' mode to '--signed-tags=<mode>'
  fast-import: add 'sign-if-invalid' mode to '--signed-tags=<mode>'
  fast-import: add 'strip-if-invalid' mode to '--signed-tags=<mode>'
  fast-import: add 'abort-if-invalid' mode to '--signed-commits=<mode>'
  fast-export: check for unsupported signing modes earlier

The check in "receive-pack" to prevent a checked out branch from
getting updated via updateInstead mechanism has been corrected.

* ps/receive-pack-updateinstead-in-worktree:
  receive-pack: use worktree HEAD for updateInstead
  t5516: clean up cloned and new-wt in denyCurrentBranch and worktrees test
  t5516: test updateInstead with worktree and unborn bare HEAD

Test clean-up.

* ss/t7004-unhide-git-failures:
  t7004: replace wc -l with modern test helpers

Further work to adjust the codebase for C23 that changes functions
like strchr() that discarded constness when they return a pointer into
a const string to preserve constness.

* jk/c23-const-preserving-fixes-more:
  refs/files-backend: drop const to fix strchr() warning
  http: drop const to fix strstr() warning
  range-diff: drop const to fix strstr() warnings
  pkt-line: make packet_reader.line non-const
  skip_prefix(): check const match between in and out params
  pseudo-merge: fix disk reads from find_pseudo_merge()
  find_last_dir_sep(): convert inline function to macro
  run-command: explicitly cast away constness when assigning to void
  pager: explicitly cast away strchr() constness
  transport-helper: drop const to fix strchr() warnings
  http: add const to fix strchr() warnings
  convert: add const to fix strchr() warnings

Various code clean-up around odb subsystem.

* ps/odb-cleanup:
  odb: drop unneeded headers and forward decls
  odb: rename `odb_has_object()` flags
  odb: use enum for `odb_write_object` flags
  odb: rename `odb_write_object()` flags
  treewide: use enum for `odb_for_each_object()` flags
  CodingGuidelines: document our style for flags

Code cleanup.

* jd/cache-tree-trace-wo-the-repository:
  cache-tree: use index state repository in trace2 calls

Update reftable library part with what is used in libgit2 to improve
portability to different target codebases and platforms.

* ps/reftable-portability:
  reftable/system: add abstraction to mmap files
  reftable/system: add abstraction to retrieve time in milliseconds
  reftable/fsck: use REFTABLE_UNUSED instead of UNUSED
  reftable/stack: provide fsync(3p) via system header
  reftable: introduce "reftable-system.h" header

add_files_to_cache() used diff_files() to detect only the paths that
are different between the index and the working tree and add them,
which does not need rename detection, which interfered with unnecessary
conflicts.

* ng/add-files-to-cache-wo-rename:
  read-cache: disable renames in add_files_to_cache

The way dash 0.5.13 handles non-ASCII contents in here-doc
is buggy and breaks our existing tests, which unfortunately
have been rewritten to avoid triggering the bug.

* ps/dash-buggy-0.5.13-workaround:
  t9300: work around partial read bug in Dash v0.5.13
  t: work around multibyte bug in quoted heredocs with Dash v0.5.13

The experimental `git replay` command learned the `--ref=<ref>` option
to allow specifying which ref to update, overriding the default behavior.

* tc/replay-ref:
  replay: allow to specify a ref with option --ref
  replay: use stuck form in documentation and help message
  builtin/replay: mark options as not negatable

* js/mingw-use-strftime-directly-in-ucrt-build:
  mingw: use strftime() directly in UCRT builds

* js/cmake-needs-writev-compat-too:
  cmake: use writev(3p) wrapper as needed

Further work to adjust the codebase for C23 that changes functions
like strchr() that discarded constness when they return a pointer into
a const string to preserve constness.

* jk/c23-const-preserving-fixes-more:
  git-compat-util: fix CONST_OUTPARAM typo and indentation

"git backfill" is capable of auto-detecting a sparsely checked out
working tree, which was broken.

* th/backfill-auto-detect-sparseness-fix:
  backfill: auto-detect sparse-checkout from config

Glitches in "git history -h" have been corrected.

* rs/history-short-help-fix:
  history: fix short help for argument of --update-refs

"git config list" is the official way to spell "git config -l" and
"git config --list".  Use it to update the documentation.

* kh/doc-config-list:
  doc: gitcvs-migration: rephrase “man page”
  doc: replace git config --list/-l with `list`

"git rev-list --maximal-only" has been optimized by borrowing the
logic used by "git show-branch --independent", which computes the
same kind of information much more efficiently.

* ds/rev-list-maximal-only-optim:
  rev-list: use reduce_heads() for --maximal-only
  p6011: add perf test for rev-list --maximal-only
  t6600: test --maximal-only and --independent

* jt/index-fd-wo-repo-regression-fix:
  object-file: avoid ODB transaction when not writing objects

index.skipHash (Scalar default) and split-index are incompatible:
the shared index gets a null OID when skipHash skips computing the
hash, and the null OID causes the shared index to not be loaded on
re-read.  This triggers a BUG assertion in fsmonitor when the
fsmonitor_dirty bitmap references more entries than the (now empty)
index has.

Disable GIT_TEST_SPLIT_INDEX in the scalar clone tests that hit
this: tests 12, 13, and 22 in t9210 (matching the existing
workaround in test 16), and all of t9211 (every test does scalar
clone).

Signed-off-by: Paul Tarjan <github@paulisageek.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

`git ls-files --modified` and `git ls-files --deleted` have been
optimized to filter with pathspec before calling lstat() when there is
only a single pathspec item, avoiding unnecessary filesystem access
for entries that will not be shown.

* td/ls-files-pathspec-prefilter:
  ls-files: filter pathspec before lstat

The UNUSED macro in 'compat/posix.h' has been updated to use a
newly introduced GIT_CLANG_PREREQ macro for compiler version
checks, and the existing GIT_GNUC_PREREQ macro has been modernized
to use explicit major/minor comparisons rather than bit-shifting.

* dl/posix-unused-warning-clang:
  compat/posix.h: simplify GIT_GNUC_PREREQ() comparison
  compat/posix.h: clean up GIT_GNUC_PREREQ() and UNUSED
  compat/posix.h: enable UNUSED warning messages for Clang

compute_reachable_generation_numbers() in commit-graph used a 32-bit
integer to accumulate parent generations, which is OK for generation
number v1 (topological levels), but with generation number v2
(adjusted committer timestamps), it truncated timestamps beyond
2106.  Fixed by widening the accumulator to timestamp_t.

* en/commit-graph-timestamp-fix:
  commit-graph: use timestamp_t for max parent generation accumulator

* js/osxkeychain-build-wo-rust:
  osxkeychain: fix build with Rust

Project-specific configuration for b4 has been introduced, and the
documentation has been updated to recommend using it as a
streamlined method for submitting patches.

* ps/doc-recommend-b4:
  b4: introduce configuration for the Git project
  MyFirstContribution: recommend the use of b4
  MyFirstContribution: recommend shallow threading of cover letters

* rs/cat-file-default-format-optim:
  cat-file: speed up default format

* kw/gitattributes-typofix:
  gitattributes: fix eol attribute for Perl scripts

A regression in the error diagnosis code for invalid .git files has
been fixed, avoiding a potential NULL-pointer crash when reporting
that a .git file does not point to a valid repository.

* jk/setup-gitfile-diag-fix:
  read_gitfile(): simplify NOT_A_REPO error message

"ort" merge backend handles merging corrupt trees better by
aborting when it should.

* en/ort-harden-against-corrupt-trees:
  cache-tree: fix verify_cache() to catch non-adjacent D/F conflicts
  merge-ort: abort merge when trees have duplicate entries
  merge-ort: free diff pairs queue in clear_or_reinit_internal_opts()
  merge-ort: drop unnecessary show_all_errors from collect_merge_info()
  merge-ort: propagate callback errors from traverse_trees_wrapper()

A hotfix to an earlier attempt to update code paths that assumed
"unsigned long" was long enough for "size_t".

* js/objects-larger-than-4gb-on-windows:
  zlib: properly clamp to uLong

* js/objects-larger-than-4gb-on-windows-more:
  odb: use size_t for object_info.sizep and the size APIs
  packfile,delta: drop the `cast_size_t_to_ulong()` wrappers
  pack-objects: use size_t for in-core object sizes
  packfile: widen unpack_entry()'s size out-parameter to size_t
  pack-objects(check_pack_inflate()): use size_t instead of unsigned long
  patch-delta: use size_t for sizes
  compat/msvc: use _chsize_s for ftruncate

Commands that list branches and tags (like git branch and git tag)
have been optimized to pass the namespace prefix when initializing
their ref iterator, avoiding a loose-ref scaling regression in
repositories with many unrelated loose references.

* td/ref-filter-restore-prefix-iteration:
  ref-filter: restore prefix-scoped iteration

The packed object source has been refactored into a proper struct
odb_source.

* ps/odb-source-packed:
  odb/source-packed: drop pointer to "files" parent source
  midx: refactor interfaces to work on "packed" source
  odb/source-packed: stub out remaining functions
  odb/source-packed: wire up `freshen_object()` callback
  odb/source-packed: wire up `find_abbrev_len()` callback
  odb/source-packed: wire up `count_objects()` callback
  odb/source-packed: wire up `for_each_object()` callback
  odb/source-packed: wire up `read_object_stream()` callback
  odb/source-packed: wire up `read_object_info()` callback
  packfile: use higher-level interface to implement `has_object_pack()`
  odb/source-packed: wire up `reprepare()` callback
  odb/source-packed: wire up `close()` callback
  odb/source-packed: start converting to a proper `struct odb_source`
  odb/source-packed: store pointer to "files" instead of generic source
  packfile: move packed source into "odb/" subsystem
  packfile: split out packfile list logic
  packfile: rename `struct packfile_store` to `odb_source_packed`

The global configuration variables protect_hfs and protect_ntfs have
been migrated into struct repo_config_values to tie them to
per-repository configuration state.

* ty/move-protect-hfs-ntfs:
  environment: use 'repo->initialized' for repo_protect_hfs() and repo_protect_ntfs()

Support for hashing loose or packed objects larger than 4GB on Windows
and other LLP64 platforms has been improved by converting object header
buffers and data-handling functions from 'unsigned long' to 'size_t'.

* po/hash-object-size-t:
  hash-object: add a >4GB/LLP64 test case using filtered input
  hash-object: add another >4GB/LLP64 test case
  hash-object --stdin: verify that it works with >4GB/LLP64
  hash algorithms: use size_t for section lengths
  object-file.c: use size_t for header lengths
  hash-object: demonstrate a >4GB/LLP64 problem

Wean the Windows builds in GitLab CI procedure away from
(unfortunately unreliable) Chocolatey to install dependencies.

* ps/gitlab-ci-windows:
  gitlab-ci: migrate Windows builds away from Chocolatey

* js/win32-localtime-r:
  win32: ensure that `localtime_r()` is declared even in i686 builds

The `fetch.followRemoteHEAD` configuration variable has been added to
provide a default for the per-remote `remote.<name>.followRemoteHEAD`
setting.

* mh/fetch-follow-remote-head-config:
  fetch: fixup a misaligned comment
  fetch: add configuration variable fetch.followRemoteHEAD
  fetch: refactor do_fetch handling of followRemoteHEAD
  fetch: return 0 on known git_fetch_config
  fetch: rename function report_set_head
  t5510: cleanup remote in followRemoteHEAD dangling ref test
  doc: explain fetchRemoteHEADWarn advice
  fetch: fixup set_head advice for warn-if-not-branch

The trailer sections in SubmittingPatches have been updated to
encourage use of standard trailers.

* kh/submittingpatches-trailers:
  SubmittingPatches: note that trailer order matters
  SubmittingPatches: be consistent with trailer markup
  SubmittingPatches: document Based-on-patch-by trailer
  SubmittingPatches: discourage common Linux trailers
  SubmittingPatches: encourage trailer use for substantial help

Xcode 15 and later has a linker set to complain when the same library
archive is listed twice on the command line.  Squelch the annoyance.

* hn/macos-linker-warning:
  config.mak.uname: avoid macOS dup-library warning

When building Git with Clang on Linux with DEVELOPER=1, the build fails
because Clang treats C11 features used in glibc headers as extensions
and raises errors due to -std=gnu99, -pedantic, and -Werror.

Specifically, glibc's string.h uses _Generic (a C11 feature) in macros
like strchr. When these macros are expanded in Git's C files, Clang
warns about them being C11 extensions.

GCC does not exhibit this behavior because it suppresses pedantic
warnings for macros defined in system headers.

To fix this, add -Wno-c11-extensions to DEVELOPER_CFLAGS when using
Clang, but restrict it to Linux (uname_S == Linux). This suppresses
the warning for glibc headers while keeping the build strict on other
platforms (like macOS) to catch accidental C11 usage in Git's own code.

Signed-off-by: Shnatu <snatu@google.com>