The iconv library on macOS fails to correctly handle stateful
ISO/IEC 2022 encoded strings. Work it around instead of replacing
it wholesale from homebrew.
* tb/macos-iconv-workarounds:
utf8.c: enable workaround for iconv under macOS 14/15
utf8.c: prepare workaround for iconv under macOS 14/15
The split command in "git subtree" (in contrib/) has been taught to
deal better with rebased history.
* cs/rebased-subtree-split:
contrib/subtree: detect rewritten subtree commits
The previous commit introduced a workaround in utf8.c to deal
with broken iconv implementations.
It is enabled when a MacOS version is used that has a buggy
iconv library and there is no external library provided
(and linked against) from neither MacPorts nor Homebrew nor Fink.
For Homebrew, MacPorts and Fink we check if libiconv exist.
Introduce 2 new macros: HAS_GOOD_LIBICONV and NEEDS_GOOD_LIBICONV.
For Homebrew HAS_GOOD_LIBICONV is set when the libiconv directory
exist.
MacPorts can be installed with or without libiconv, so check if
libiconv.dylib exists (which is a softlink)
Fink compiles and installs libiconv by default.
Note that a fresh installation of Fink now defaults to /opt/sw.
Older versions used /sw as default, so leave the check and setting
of BASIC_CFLAGS and BASIC_LDFLAGS as is.
For the new default check for the existance of /opt/sw as well.
Add a check for /opt/sw/lib/libiconv.dylib which sets HAS_GOOD_LIBICONV
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
MacOS14 (Sonoma) has started to ship an iconv library with bugs.
The same bugs exists even in MacOS 15 (Sequoia)
A bug report running the Git test suite says:
three tests of t3900 fail on macOS 26.1 for me:
not ok 17 - ISO-2022-JP should be shown in UTF-8 now
not ok 25 - ISO-2022-JP should be shown in UTF-8 now
not ok 38 - commit --fixup into ISO-2022-JP from UTF-8
Here's the verbose output of the first one:
=================
expecting success of 3900.17 'ISO-2022-JP should be shown in UTF-8 now':
compare_with ISO-2022-JP "$TEST_DIRECTORY"/t3900/2-UTF-8.txt
--- /Users/x/src/git/t/t3900/2-UTF-8.txt 2024-10-01 19:43:24.605230684 +0000
+++ current 2025-12-08 21:52:45.786161909 +0000
@@ -1,5 +1,5 @@
はれひほふ
しているのが、いるので。
-濱浜ほれぷりぽれまびぐりろへ。
+濱浜ほれぷりぽれまび$0$j$m$X!#
not ok 17 - ISO-2022-JP should be shown in UTF-8 now
1..17
=================
compare_with runs git show to display a commit message, which in this
case here was encoded using ISO-2022-JP and is supposed to be reencoded
to UTF-8, but git show only does that half-way -- the "$0$j$m$X!#" part
is from the original ISO-2022-JP representation.
That botched conversion is done by utf8.c::reencode_string_iconv(). It
calls iconv(3) to do the actual work, initially with an output buffer of
the same size as the input. If the output needs more space the function
enlarges the buffer and calls iconv(3) again.
iconv(3) won't tell us how much space it needs, but it will report what
part it already managed to convert, so we can increase the buffer and
continue from there. ISO-2022-JP has escape codes for switching between
character sets, so it's a stateful encoding. I guess the iconv(3) on my
machine forgets the state at the end of part one and then messes up part
two.
[end of citation]
Working around the buggy iconv shipped with the OS can be done in
two ways:
a) Link Git against a different version of iconv
b) Improve the handling when iconv needs a larger output buffer
a) is already done by default when either Fink [1] or MacPorts [2]
or Homebrew [3] is installed.
b) is implemented here, in case that no fixed iconv is available:
When the output buffer is too short, increase it (as before)
and start from scratch (this is new).
This workound needs to be enabled with
'#define ICONV_RESTART_RESET'
and a makefile knob will be added in the next commit
Suggested-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
[1] https://www.finkproject.org/
[2] https://www.macports.org/
[3] https://brew.sh/
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git fsck" used inconsistent set of refs to show a confused
warning, which has been corrected.
* en/fsck-snapshot-ref-state:
fsck: snapshot default refs before object walk
Code clean-up, unifying various hand-rolled "list of commit
objects" and use the commit_stack API.
* rs/commit-stack:
commit-reach: use commit_stack
commit-graph: use commit_stack
commit: add commit_stack_grow()
shallow: use commit_stack
pack-bitmap-write: use commit_stack
commit: add commit_stack_init()
test-reach: use commit_stack
remote: use commit_stack for src_commits
remote: use commit_stack for sent_tips
remote: use commit_stack for local_commits
name-rev: use commit_stack
midx: use commit_stack
log: use commit_stack
revision: export commit_stack
Diagnose invalid bundle-URI that lack the URI entry, instead of
crashing.
* sb/bundle-uri-without-uri:
bundle-uri: validate that bundle entries have a uri
More doc style updates.
* ja/doc-synopsis-style-more:
doc: convert git-remote to synopsis style
doc: convert git stage to use synopsis block
doc: convert git-status tables to AsciiDoc format
doc: convert git-status to synopsis style
doc: fix t0450-txt-doc-vs-help to select only first synopsis block
"git patch-id" documentation updates.
* kh/doc-patch-id:
doc: patch-id: --verbatim locks in --stable
doc: patch-id: spell out the git-diff-tree(1) form
doc: patch-id: use definite article for the result
patch-id: use “patch ID” throughout
doc: patch-id: capitalize Git version
doc: patch-id: don’t use semicolon between bullet points
Update a FAQ entry on synching two separate repositories using the
"git stash export/import" recently introduced.
* bc/doc-stash-import-export:
gitfaq: document using stash import/export to sync working tree
git subtree split --prefix P
detects splits that are outside of path prefix `P` and prunes
them from history graph processing. This improves the performance
of repeated `split --rejoin` with many different prefixes.
Both before and after 83f9dad7d6 (contrib/subtree: fix split with
squashed subtrees, 2025-09-09), the pruning logic does not detect
**rebased** or **cherry-picked** git-subtree commits. If `split`
encounters any of these commits, the split output may have
incomplete history.
All commits authored by
git subtree merge [--squash] --prefix Q
have a first or second parent that has *only* subtree commits
as ancestors. When splitting a completely different path `P/`,
it is safe to ignore:
1. the merged tree
2. the subtree parent
3. *all* of that parent's ancestry, which applies only to
path `Q/` and not `P/`.
But this relationship no longer holds if the git-subtree commit
is rebased or otherwise reauthored. After a rebase, the former
git-subtree commit will have other unrelated commits as ancestors.
Ignoring these commits may exclude the history of `P/`,
leading to incomplete `subtree split` output.
The pruning logic relies solely on the `git-subtree-*:` trailers
to detect git-subtree commits, which it blindly accepts without
further validation. The split logic also takes its time about
being wrong: `cmd_split()` execs a `git show` for *every* commit
in the split range… twice. This is inefficient in a shell script.
Add a "reality check" to ignore rebased or rewritten commits:
* Rewrites of non-merge commits cannot be detected, so the new
detector no longer looks for them.
* Merges carry a `git-subtree-mainline:` trailer with the hash of
the **first parent**. If this hash differs, or if the "merge"
commit no longer has multiple parents, a rewrite has occurred.
To increase speed, package this logic in a new method,
`find_other_splits()`. Perform the check up-front by iterating
over a single `git log`. Add ignored subtrees to:
1. the `notree` cache, which excludes them from the `split` history
2. a `prune` negative refs list. The negative refs prevent
recursing into other subtrees. Since there are potentially a
*lot* of these, cache them on disk and use rev-list's
`--stdin` mode.
Reported-by: George <george@mail.dietrich.pub>
Signed-off-by: Colin Stagner <ask+git@howdoi.land>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a compiler warning (-Werror=analyzer-deref-before-check) due to
dereferencing the options pointer before NULL checking it.
In practice run_hooks_opt() is never called with a NULL opt struct,
so this just fixes the code to not trigger the warning anymore.
The NULL check is kept as-is because some future patches might end up
calling run_hooks_opt with a NULL opt struct, which is clearly a bug.
While at it, also fix the BUG message function name.
Reported-by: correctmost <cmlists@sent.com>
Suggested-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fsck has a race when operating on live repositories; consider the
following simple script that writes new commits as fsck runs:
#!/bin/bash
git fsck &
PID=$!
while ps -p $PID >/dev/null; do
sleep 3
git commit -q --allow-empty -m "Another commit"
done
Since fsck walks objects for connectivity and then reads the refs at the
end to check, this can cause fsck to get confused and think that the new
refs refer to missing commits and that new reflog entries are invalid.
Running the above script in a clone of git.git results in the following
(output ellipsized to remove additional errors of the same type):
$ ./fsck-while-writing.sh
Checking ref database: 100% (1/1), done.
Checking object directories: 100% (256/256), done.
warning in tag d6602ec519: missingTaggerEntry: invalid format - expected 'tagger' line
Checking objects: 100% (835091/835091), done.
error: HEAD: invalid reflog entry 2aac9f9286e2164fbf8e4f1d1df53044ace2b310
error: HEAD: invalid reflog entry 2aac9f9286e2164fbf8e4f1d1df53044ace2b310
error: HEAD: invalid reflog entry da0f5b80d61844a6f0ad2ddfd57e4fdfa246ea68
error: HEAD: invalid reflog entry da0f5b80d61844a6f0ad2ddfd57e4fdfa246ea68
[...]
error: HEAD: invalid reflog entry 87c8a5c2f6b79d9afa9e941590b9a097b6f7ac09
error: HEAD: invalid reflog entry d80887a48865e6ad165274b152cbbbed29f8a55a
error: HEAD: invalid reflog entry d80887a48865e6ad165274b152cbbbed29f8a55a
error: HEAD: invalid reflog entry 6724f2dfede88bfa9445a333e06e78536c0c6c0d
error: refs/heads/mybranch invalid reflog entry 2aac9f9286e2164fbf8e4f1d1df53044ace2b310
error: refs/heads/mybranch: invalid reflog entry 2aac9f9286e2164fbf8e4f1d1df53044ace2b310
error: refs/heads/mybranch: invalid reflog entry da0f5b80d61844a6f0ad2ddfd57e4fdfa246ea68
error: refs/heads/mybranch: invalid reflog entry da0f5b80d61844a6f0ad2ddfd57e4fdfa246ea68
[...]
error: refs/heads/mybranch: invalid reflog entry 87c8a5c2f6b79d9afa9e941590b9a097b6f7ac09
error: refs/heads/mybranch: invalid reflog entry d80887a48865e6ad165274b152cbbbed29f8a55a
error: refs/heads/mybranch: invalid reflog entry d80887a48865e6ad165274b152cbbbed29f8a55a
error: refs/heads/mybranch: invalid reflog entry 6724f2dfede88bfa9445a333e06e78536c0c6c0d
Checking connectivity: 833846, done.
missing commit 6724f2dfede88bfa9445a333e06e78536c0c6c0d
Verifying commits in commit graph: 100% (242243/242243), done.
We can minimize the race opportunities by taking a snapshot of refs at
program invocation, doing the connectivity check, and then checking the
snapshotted refs afterward. This avoids races with regular refs between
fsck and adding objects to the database, though it still leaves a race
between a gc and fsck. We are less concerned about folks simultaneously
running gc with fsck; though, if it becomes an issue, we could lock fsck
during gc. We definitely do not want to lock fsck during operations
that may add objects to the object store; that would be problematic for
forges.
Note that refs aren't the only problem, though; reflog entries and index
entries could be problematic as well. For now we punt on index entries
just leaving a TODO comment, and for reflogs we use a coarse solution of
taking the time at the beginning of the program and ignoring reflog
entries newer than that time. That may be imperfect if dealing with a
network filesystem, so we leave TODO comment for those that want to
improve that handling as well.
As a high level overview:
* In addition to fsck_handle_ref(), which now is only a few lines long
to process a ref, there's also a snapshot_ref() which is called
early in the program for each ref and takes all the error checking
logic.
* The iterating over refs that used to be in get_default_heads() plus
a loop over the arguments now appears in shapshot_refs().
* There's a new process_refs() as well that kind of looks like the old
get_default_heads() though it is streamlined due to the work done by
snapshot_refs().
This combination of changes modifies the output of running the script
(from the beginning of this commit message) to:
$ ./fsck-while-writing.sh
Checking ref database: 100% (1/1), done.
Checking object directories: 100% (256/256), done.
warning in tag d6602ec519: missingTaggerEntry: invalid format - expected 'tagger' line
Checking objects: 100% (835091/835091), done.
Checking connectivity: 833846, done.
Verifying commits in commit graph: 100% (242243/242243), done.
While worries about live updates while running fsck is likely of most
interest for forge operators, it may also benefit those with
automated jobs (such as git maintenance) or even casual users who want
to do other work in their clone while fsck is running.
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The documentation for the builtin API was moved from the technical
documentation and into a comment in builtin.h by ec14d4ecb5 (builtin.h: take
over documentation from api-builtin.txt, 2017-08-02). This documentation
wasn't updated as part of the major overhaul to include a repository struct
in 9b1cb5070f (builtin: add a repository parameter for builtin functions,
2024-09-13).
There was a brief update regarding the move from *.txt to *.adoc by
e8015223c7 (builtin.h: *.txt -> *.adoc fixes, 2025-03-03).
I noticed that there was quite a bit missing from the old documentation,
which is still visible on git-scm.com [1].
[1] https://github.com/git/git-scm.com/issues/2124
This change updates the documentation in the following ways:
1. Updates the cmd_foo() prototype to include a repository.
2. Adds some newlines to have uniformity in the list of flags.
3. Adds a description of the NO_PARSEOPT flag.
4. Describes the tests that perform checks on all builtins, which may trip
up a contributor working on a new builtin.
I double-checked these instructions against a toy example in my local branch
to be sure that it was complete.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace old-style `test -[df]` and `! test -[df]` assertions with
the modern `test_path_is_file`, `test_path_is_dir`, and
`test_path_is_missing` helpers.
These helpers provide more informative error messages in case of
failure (e.g., "File 'foo' is missing" instead of just exit code 1).
While at it, fix a typo and an incorrect path
reference in one of the test descriptions.
Signed-off-by: K Jayatheerth <jayatheerthkulkarni2005@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git 2.51 learned how to import and export stashes. This is a
secure and robust way to transfer working tree states across machines
and comes with almost none of the pitfalls of rsync or other tools.
Recommend this as an alternative in the FAQ.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
- Use _<placeholder>_ instead of <placeholder> in the description
- Use _underscores_ around math associated with <placeholders>
- Use `backticks` for keywords and more complex option
descriptions. The new rendering engine will apply synopsis rules to
these spans.
Signed-off-by: Michael Lyons <git@michael.lyo.nz>
Acked-by: Jean-Noël AVILA <jn.avila@free.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
- Use _<placeholder>_ instead of <placeholder> in the description
- Modify some samples to use <placeholders>
- Use `backticks` for keywords and more complex option
descriptions. The new rendering engine will apply synopsis rules to
these spans.
Signed-off-by: Michael Lyons <git@michael.lyo.nz>
Acked-by: Jean-Noël AVILA <jn.avila@free.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The default `--unstable` is a legacy format that predates `--stable`.
That’s why 2871f4d4 (builtin: patch-id: add --verbatim as a command mode,
2022-10-24) made `--verbatim` lock in[1] `--stable`:
Users of --unstable mainly care about compatibility with old git
versions, which unstripping the whitespace would break. Thus there
isn't a usecase for the combination of --verbatim and --unstable,
and we don't expose this so as to not add maintainence burden.
† 1: imply `--stable`, disallow `--unstable`
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
You specifically need `--patch` since the default output is a raw diff.
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The “Description” section decided to introduce and use the term “patch
ID” for the ID value itself. Let’s use the same term on the options as
well.
Also make to sure to use bare “ID” instead of “id”.
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These bullet points are full-fledged paragraphs with sentences. It’s
best to restrict semicolon-termination to the case when the bullet list
amounts to a list of items.[1]
† 1: Like “List: ... • first; ... • second; and ... • third.”
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Import newer version of "clar", unit testing framework.
* ps/clar-integers:
gitattributes: disable blank-at-eof errors for clar test expectations
t/unit-tests: demonstrate use of integer comparison assertions
t/unit-tests: update clar to 39f11fe
Test coverage of "git replay" has been improved.
* kh/replay-invalid-onto-advance:
t3650: add more regression tests for failure conditions
replay: die if we cannot parse object
replay: improve code comment and die message
replay: die descriptively when invalid commit-ish is given
replay: find *onto only after testing for ref name
replay: remove dead code and rearrange
Miscellaneous fixes on object database layer.
* ps/odb-misc-fixes:
odb: properly close sources before freeing them
builtin/gc: fix condition for whether to write commit graphs
The ort merge machinery hit an assertion failure in a history with
criss-cross merges renamed a directory and a non-directory, which
has been corrected.
* en/ort-recursive-d-f-conflict-fix:
merge-ort: fix corner case recursive submodule/directory conflict handling
Running "git diff" with "--name-only" and other options that allows
us not to look at the blob contents, while objects that are lazily
fetched from a promisor remote, caused use-after-free, which has
been corrected.
* ds/diff-lazy-fetch-with-name-only-fix:
diff: avoid segfault with freed entries
Code clean-up.
* rs/tag-wo-the-repository:
tag: stop using the_repository
tag: support arbitrary repositories in parse_tag()
tag: support arbitrary repositories in gpg_verify_tag()
tag: use algo of repo parameter in parse_tag_buffer()
This test indirectly checks that the lost-found folder has 2 files in it
and then checks that the expected two files exist. Make this more
deliberate by removing the old test -f and compare the actual ls of the
lost-found directory with the expected files.
Signed-off-by: Andrew Chitester <andchi@fastmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is possible to hit a memory leak when reading data from a submodule
via git-grep(1):
Direct leak of 192 byte(s) in 1 object(s) allocated from:
#0 0x55555562e726 in calloc (git+0xda726)
#1 0x555555964734 in xcalloc ../wrapper.c:154:8
#2 0x555555835136 in load_multi_pack_index_one ../midx.c:135:2
#3 0x555555834fd6 in load_multi_pack_index ../midx.c:382:6
#4 0x5555558365b6 in prepare_multi_pack_index_one ../midx.c:716:17
#5 0x55555586c605 in packfile_store_prepare ../packfile.c:1103:3
#6 0x55555586c90c in packfile_store_reprepare ../packfile.c:1118:2
#7 0x5555558546b3 in odb_reprepare ../odb.c:1106:2
#8 0x5555558539e4 in do_oid_object_info_extended ../odb.c:715:4
#9 0x5555558533d1 in odb_read_object_info_extended ../odb.c:862:8
#10 0x5555558540bd in odb_read_object ../odb.c:920:6
#11 0x55555580a330 in grep_source_load_oid ../grep.c:1934:12
#12 0x55555580a13a in grep_source_load ../grep.c:1986:10
#13 0x555555809103 in grep_source_is_binary ../grep.c:2014:7
#14 0x555555807574 in grep_source_1 ../grep.c:1625:8
#15 0x555555807322 in grep_source ../grep.c:1837:10
#16 0x5555556a5c58 in run ../builtin/grep.c:208:10
#17 0x55555562bb42 in void* ThreadStartFunc<false>(void*) lsan_interceptors.cpp.o
#18 0x7ffff7a9a979 in start_thread (/nix/store/xx7cm72qy2c0643cm1ipngd87aqwkcdp-glibc-2.40-66/lib/libc.so.6+0x9a979) (BuildId: cddea92d6cba8333be952b5a02fd47d61054c5ab)
#19 0x7ffff7b22d2b in __GI___clone3 (/nix/store/xx7cm72qy2c0643cm1ipngd87aqwkcdp-glibc-2.40-66/lib/libc.so.6+0x122d2b) (BuildId: cddea92d6cba8333be952b5a02fd47d61054c5ab)
The root caues of this leak is the way we set up and release the
submodule:
1. We use `repo_submodule_init()` to initialize a new repository. This
repository is stored in `repos_to_free`.
2. We now read data from the submodule repository.
3. We then call `repo_clear()` on the submodule repositories.
4. `repo_clear()` calls `odb_free()`.
5. `odb_free()` calls `odb_free_sources()` followed by `odb_close()`.
The issue here is the 5th step: we call `odb_free_sources()` _before_ we
call `odb_close()`. But `odb_free_sources()` already frees all sources,
so the logic that closes them in `odb_close()` now becomes a no-op. As a
consequence, we never explicitly close sources at all.
Fix the leak by closing the store before we free the sources.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When performing auto-maintenance we check whether commit graphs need to
be generated by counting the number of commits that are reachable by any
reference, but not covered by a commit graph. This search is performed
by iterating through all references and then doing a depth-first search
until we have found enough commits that are not present in the commit
graph.
This logic has a memory leak though:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x55555562e433 in malloc (git+0xda433)
#1 0x555555964322 in do_xmalloc ../wrapper.c:55:8
#2 0x5555559642e6 in xmalloc ../wrapper.c:76:9
#3 0x55555579bf29 in commit_list_append ../commit.c:1872:35
#4 0x55555569f160 in dfs_on_ref ../builtin/gc.c:1165:4
#5 0x5555558c33fd in do_for_each_ref_iterator ../refs/iterator.c:431:12
#6 0x5555558af520 in do_for_each_ref ../refs.c:1828:9
#7 0x5555558ac317 in refs_for_each_ref ../refs.c:1833:9
#8 0x55555569e207 in should_write_commit_graph ../builtin/gc.c:1188:11
#9 0x55555569c915 in maintenance_is_needed ../builtin/gc.c:3492:8
#10 0x55555569b76a in cmd_maintenance ../builtin/gc.c:3542:9
#11 0x55555575166a in run_builtin ../git.c:506:11
#12 0x5555557502f0 in handle_builtin ../git.c:779:9
#13 0x555555751127 in run_argv ../git.c:862:4
#14 0x55555575007b in cmd_main ../git.c:984:19
#15 0x5555557523aa in main ../common-main.c:9:11
#16 0x7ffff7a2a4d7 in __libc_start_call_main (/nix/store/xx7cm72qy2c0643cm1ipngd87aqwkcdp-glibc-2.40-66/lib/libc.so.6+0x2a4d7) (BuildId: cddea92d6cba8333be952b5a02fd47d61054c5ab)
#17 0x7ffff7a2a59a in __libc_start_main@GLIBC_2.2.5 (/nix/store/xx7cm72qy2c0643cm1ipngd87aqwkcdp-glibc-2.40-66/lib/libc.so.6+0x2a59a) (BuildId: cddea92d6cba8333be952b5a02fd47d61054c5ab)
#18 0x5555555f0934 in _start (git+0x9c934)
The root cause of this memory leak is our use of `commit_list_append()`.
This function expects as parameters the item to append and the _tail_ of
the list to append. This tail will then be overwritten with the new tail
of the list so that it can be used in subsequent calls. But we call it
with `commit_list_append(parent->item, &stack)`, so we end up losing
everything but the new item.
This issue only surfaces when counting merge commits. Next to being a
memory leak, it also shows that we're in fact miscounting as we only
respect children of the last parent. All previous parents are discarded,
so their children will be disregarded unless they are hit via another
reference.
While crafting a test case for the issue I was puzzled that I couldn't
establish the proper border at which the auto-condition would be
fulfilled. As it turns out, there's another bug: if an object is at the
tip of any reference we don't mark it as seen. Consequently, if it is
the tip of or reachable via another ref, we'd count that object multiple
times.
Fix both of these bugs so that we properly count objects without leaking
any memory.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>