Last-minute fix for a regression in "git blame --abbrev=<length>"
when insane <length> is specified; we used to correctly cap it to
the hash output length but broke it during the cycle.
* ps/build-sign-compare:
builtin/blame: fix out-of-bounds write with blank boundary commits
builtin/blame: fix out-of-bounds read with excessive `--abbrev`
When passing the `-b` flag to git-blame(1), then any blamed boundary
commits which were marked as uninteresting will not get their actual
commit ID printed, but will instead be replaced by a couple of spaces.
The flag can lead to an out-of-bounds write as though when combined with
`--abbrev=` when the abbreviation length is longer than `GIT_MAX_HEXSZ`
as we simply use memset(3p) on that array with the user-provided length
directly. The result is most likely that we segfault.
An obvious fix would be to cull `length` to `GIT_MAX_HEXSZ` many bytes.
But when the underlying object ID is SHA1, and if the abbreviated length
exceeds the SHA1 length, it would cause us to print more bytes than
desired, and the result would be misaligned.
Instead, fix the bug by computing the length via strlen(3p). This makes
us write as many bytes as the formatted object ID requires and thus
effectively limits the length of what we may end up printing to the
length of its hash. If `--abbrev=` asks us to abbreviate to something
shorter than the full length of the underlying hash function it would be
handled by the call to printf(3p) correctly.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 6411a0a896 (builtin/blame: fix type of `length` variable when
emitting object ID, 2024-12-06) we have fixed the type of the `length`
variable. In order to avoid a cast from `size_t` to `int` in the call to
printf(3p) with the "%.*s" formatter we have converted the code to
instead use fwrite(3p), which accepts the length as a `size_t`.
It was reported though that this makes us read over the end of the OID
array when the provided `--abbrev=` length exceeds the length of the
object ID. This is because fwrite(3p) of course doesn't stop when it
sees a NUL byte, whereas printf(3p) does.
Fix the bug by reverting back to printf(3p) and culling the provided
length to `GIT_MAX_HEXSZ` to keep it from overflowing when cast to an
`int`.
Reported-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As indicated by the `#undef malloc` line in `reftable/basics.h`, it is
quite common to use allocators other than the default one by defining
`malloc` constants and friends.
This pattern is used e.g. in Git for Windows, which uses the powerful
and performant `mimalloc` allocator.
Furthermore, in `reftable/basics.c` this `#undef malloc` is
_specifically_ disabled by virtue of defining the
`REFTABLE_ALLOW_BANNED_ALLOCATORS` constant before including
`reftable/basic.h`, to ensure that such a custom allocator is also used
in the reftable code.
However, in 8db127d43f (reftable: avoid leaks on realloc error,
2024-12-28) and in 2cca185e85 (reftable: fix allocation count on
realloc error, 2024-12-28), `reftable_set_alloc()` function calls were
introduced that pass `malloc`, `realloc` and `free` function pointers as
parameters _after_ `reftable/basics.h` ensured that they were no longer
`#define`d. This would override the custom allocator and re-set it to
the default allocator provided by, say, libc or MSVCRT.
This causes problems because those calls happen after the initial
allocator has already been used to initialize an array, which is
subsequently resized using the overridden default `realloc()` allocator.
You cannot mix and match allocators like that, which leads to a
`STATUS_HEAP_CORRUPTION` (C0000374) on Windows, and when running this
unit test through shell and/or `prove` (which only support 7-bit status
codes), it surfaces as exit code 127.
It is actually unnecessary to use those function pointers to
`malloc`/`realloc`/`free`, though: The `reftable` code goes out of its
way to fall back to the initial allocator when passing `NULL` parameters
instead. So let's do that instead of causing heap corruptions.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Acked-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The build procedure based on meson learned to generate HTML
documention pages.
* ps/build-meson-html:
Documentation: wire up sanity checks for Meson
t/Makefile: make "check-meson" work with Dash
meson: install static files for HTML documentation
meson: generate articles
Documentation: refactor "howto-index.sh" for out-of-tree builds
Documentation: refactor "api-index.sh" for out-of-tree builds
meson: generate user manual
Documentation: inline user-manual.conf
meson: generate HTML pages for all man page categories
meson: fix generation of merge tools
meson: properly wire up dependencies for our docs
meson: wire up support for AsciiDoctor
CI jobs that run threaded programs under LSan has been giving false
positives from time to time, which has been worked around.
This is an alternative to the jk/lsan-race-with-barrier topic with
much smaller change to the production code.
* jk/lsan-race-ignore-false-positive:
test-lib: ignore leaks in the sanitizer's thread code
test-lib: check leak logs for presence of DEDUP_TOKEN
test-lib: simplify leak-log checking
test-lib: rely on logs to detect leaks
Revert barrier-based LSan threading race workaround
Our CI jobs sometimes see false positive leaks like this:
=================================================================
==3904583==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 32 byte(s) in 1 object(s) allocated from:
#0 0x7fa790d01986 in __interceptor_realloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:98
#1 0x7fa790add769 in __pthread_getattr_np nptl/pthread_getattr_np.c:180
#2 0x7fa790d117c5 in __sanitizer::GetThreadStackTopAndBottom(bool, unsigned long*, unsigned long*) ../../../../src/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp:150
#3 0x7fa790d11957 in __sanitizer::GetThreadStackAndTls(bool, unsigned long*, unsigned long*, unsigned long*, unsigned long*) ../../../../src/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp:598
#4 0x7fa790d03fe8 in __lsan::ThreadStart(unsigned int, unsigned long long, __sanitizer::ThreadType) ../../../../src/libsanitizer/lsan/lsan_posix.cpp:51
#5 0x7fa790d013fd in __lsan_thread_start_func ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:440
#6 0x7fa790adc3eb in start_thread nptl/pthread_create.c:444
#7 0x7fa790b5ca5b in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81
This is not a leak in our code, but appears to be a race between one
thread calling exit() while another one is in LSan's stack setup code.
You can reproduce it easily by running t0003 or t5309 with --stress
(these trigger it because of the threading in git-grep and index-pack
respectively).
This may be a bug in LSan, but regardless of whether it is eventually
fixed, it is useful to work around it so that we stop seeing these false
positives.
We can recognize it by the mention of the sanitizer functions in the
DEDUP_TOKEN line. With this patch, the scripts mentioned above should
run with --stress indefinitely.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we check the leak logs, our original strategy was to check for any
non-empty log file produced by LSan. We later amended that to ignore
noisy lines in 370ef7e40d (test-lib: ignore uninteresting LSan output,
2023-08-28).
This makes it hard to ignore noise which is more than a single line;
we'd have to actually parse the file to determine the meaning of each
line.
But there's an easy line-oriented solution. Because we always pass the
dedup_token_length option, the output will contain a DEDUP_TOKEN line
for each leak that has been found. So if we invert our strategy to stop
ignoring useless lines and only look for useful ones, we can just count
the number of DEDUP_TOKEN lines. If it's non-zero, then we found at
least one leak (it would even give us a count of unique leaks, but we
really only care if it is non-zero).
This should yield the same outcome, but will help us build more false
positive detection on top.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have a function to count the number of leaks found (actually, it is
the number of processes which produced a log file). Once upon a time we
cared about seeing if this number increased between runs. But we
simplified that away in 95c679ad86 (test-lib: stop showing old leak
logs, 2024-09-24), and now we only care if it returns any results or
not.
In preparation for refactoring it further, let's drop the counting
function entirely, and roll it into the "is it empty" check. The outcome
should be the same, but we'll be free to return a boolean "did we find
anything" without worrying about somebody adding a new call to the
counting function.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we run with sanitizers, we set abort_on_error=1 so that the tests
themselves can detect problems directly (when the buggy program exits
with SIGABRT). This has one blind spot, though: we don't always check
the exit codes for all programs (e.g., helpers like upload-pack invoked
behind the scenes).
For ASan and UBSan this is mostly fine; they exit as soon as they see an
error, so the unexpected abort of the program causes the test to fail
anyway.
But for LSan, the program runs to completion, since we can only check
for leaks at the end. And in that case we could miss leak reports. And
thus we started checking LSan logs in faececa53f (test-lib: have the
"check" mode for SANITIZE=leak consider leak logs, 2022-07-28).
Originally the logs were optional, but logs are generated (and checked)
always as of 8c1d6691bc (test-lib: GIT_TEST_SANITIZE_LEAK_LOG enabled by
default, 2024-07-11). And we even check them for each test snippet, as
of cf1464331b (test-lib: check for leak logs after every test,
2024-09-24).
So now aborting on error is superfluous for LSan! We can get everything
we need by checking the logs. And checking the logs is actually
preferable, since it gives us more control over silencing false
positives (something we do not yet do, but will soon).
So let's tell LSan to just exit normally, even if it finds leaks. We can
do so with exitcode=0, which also suppresses the abort_on_error flag.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
CI jobs that run threaded programs under LSan has been giving false
positives from time to time, which has been worked around.
* jk/lsan-race-with-barrier:
grep: work around LSan threading race with barrier
index-pack: work around LSan threading race with barrier
thread-utils: introduce optional barrier type
Revert "index-pack: spawn threads atomically"
test-lib: use individual lsan dir for --stress runs
The custom allocator code in the reftable library did not handle
failing realloc() very well, which has been addressed.
* rs/reftable-realloc-errors:
t-reftable-merged: handle realloc errors
reftable: handle realloc error in parse_names()
reftable: fix allocation count on realloc error
reftable: avoid leaks on realloc error
When storing output in test-results/, we usually give each numbered run
in a --stress set its own output file. But we don't do that for storing
LSan logs, so something like:
./t0003-attributes.sh --stress
will have many scripts simultaneously creating, writing to, and deleting
the test-results/t0003-attributes.leak directory. This can cause logs
from one run to be attributed to another, spurious failures when
creation and deletion race, and so on.
This has always been broken, but nobody noticed because it's rare to do
a --stress run with LSan (since the point is for the code to run quickly
many times in order to hit races). But if you're trying to find a race
in the leak sanitizing code, it makes sense to use these together.
We can fix it by using $TEST_RESULTS_BASE, which already incorporates
the stress job suffix.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Check reallocation errors in unit tests, like everywhere else.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When realloc(3) fails, it returns NULL and keeps the original allocation
intact. REFTABLE_ALLOC_GROW overwrites both the original pointer and
the allocation count variable in that case, simultaneously leaking the
original allocation and misrepresenting the number of storable items.
parse_names() avoids the leak by keeping the original pointer if
reallocation fails, but still increase the allocation count in such a
case as if it succeeded. That's OK, because the error handling code
just frees everything and doesn't look at names_cap anymore.
reftable_buf_add() does the same, but here it is a problem as it leaves
the reftable_buf in a broken state, with ->alloc being roughly twice as
big as the actually allocated memory, allowing out-of-bounds writes in
subsequent calls.
Reimplement REFTABLE_ALLOC_GROW to avoid leaks, keep allocation counts
in sync and still signal failures to callers while avoiding code
duplication in callers. Make it an expression that evaluates to 0 if no
reallocation is needed or it succeeded and 1 on failure while keeping
the original pointer and allocation counter values.
Adjust REFTABLE_ALLOC_GROW_OR_NULL to the new calling convention for
REFTABLE_ALLOC_GROW, but keep its support for non-size_t alloc variables
for now.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When realloc(3) fails, it returns NULL and keeps the original allocation
intact. REFTABLE_ALLOC_GROW overwrites both the original pointer and
the allocation count variable in that case, simultaneously leaking the
original allocation and misrepresenting the number of storable items.
parse_names() and reftable_buf_add() avoid leaking by restoring the
original pointer value on failure, but all other callers seem to be OK
with losing the old allocation. Add a new variant of the macro,
REFTABLE_ALLOC_GROW_OR_NULL, which plugs the leak and zeros the
allocation counter. Use it for those callers.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "check-meson" target uses process substitution to check whether
extracted contents from "meson.build" match expected contents. Process
substitution is unportable though and thus the target will fail when
using for example Dash.
Fix this by writing data into a temporary directory.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Building our "gitweb" interface is optional in our Makefile and in Meson
and not wired up at all with CMake, but disabling it causes a couple of
tests in the t950* range that pull in "t/lib-gitweb.sh". This is because
the test library knows to execute gitweb-tests based on whether or not
Perl is available, but we may have Perl available and still end up not
building gitweb e.g. with `make test NO_GITWEB=YesPlease`.
Fix this issue by wiring up a new "NO_GITWEB" build option so that we
can skip these tests in case gitweb is not built.
Note that this new build option requires us to move the configuration of
GIT-BUILD-OPTIONS to a later point in our Meson build instructions. But
as that file is only consumed by our tests at runtime this change does
not cause any issues.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace `test -f` and `test ! -f` with `test_path_is_file` and
`test_path_is_missing` for better debuggability.
While `test -f` ensures that the file exists and is a regular file,
`test_path_is_file` provides clearer error messages on failure.
On the other hand, `test ! -f` checks either the absence of a regular
file or the presence of any other filesystem object, but looking at
them in the test individually, all of them should've said `test ! -e`,
i.e. "there shouldn't be anything at given path on filesystem."
Replace these cases with `test_path_is_missing` for better
debuggability.
Helped-by: karthik nayak <karthik.188@gmail.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Meet Soni <meetsoni3017@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git refs migrate" learned to also migrate the reflog data across
backends.
* kn/reflog-migration:
refs: mark invalid refname message for translation
refs: add support for migrating reflogs
refs: allow multiple reflog entries for the same refname
refs: introduce the `ref_transaction_update_reflog` function
refs: add `committer_info` to `ref_transaction_add_update()`
refs: extract out refname verification in transactions
refs/files: add count field to ref_lock
refs: add `index` field to `struct ref_udpate`
refs: include committer info in `ref_update` struct
The meson-build procedure is integrated into CI to catch and
prevent bitrotting.
* ps/ci-meson:
ci: wire up Meson builds
t: introduce compatibility options to clar-based tests
t: fix out-of-tree tests for some git-p4 tests
Makefile: detect missing Meson tests
meson: detect missing tests at configure time
t/unit-tests: rename clar-based unit tests to have a common prefix
Makefile: drop -DSUPPRESS_ANNOTATED_LEAKS
ci/lib: support custom output directories when creating test artifacts
"git range-diff" learned to optionally show and compare merge
commits in the ranges being compared, with the --diff-merges
option.
* js/range-diff-diff-merges:
range-diff: introduce the convenience option `--remerge-diff`
range-diff: optionally include merge commits' diffs in the analysis
Regression fix for 'show-index' when run outside of a repository.
* as/show-index-uninitialized-hash:
t5300: add test for 'show-index --object-format'
show-index: fix uninitialized hash function
Start working to make the codebase buildable with -Wsign-compare.
* ps/build-sign-compare:
t/helper: don't depend on implicit wraparound
scalar: address -Wsign-compare warnings
builtin/patch-id: fix type of `get_one_patchid()`
builtin/blame: fix type of `length` variable when emitting object ID
gpg-interface: address -Wsign-comparison warnings
daemon: fix type of `max_connections`
daemon: fix loops that have mismatching integer types
global: trivial conversions to fix `-Wsign-compare` warnings
pkt-line: fix -Wsign-compare warning on 32 bit platform
csum-file: fix -Wsign-compare warning on 32-bit platform
diff.h: fix index used to loop through unsigned integer
config.mak.dev: drop `-Wno-sign-compare`
global: mark code units that generate warnings with `-Wsign-compare`
compat/win32: fix -Wsign-compare warning in "wWinMain()"
compat/regex: explicitly ignore "-Wsign-compare" warnings
git-compat-util: introduce macros to disable "-Wsign-compare" warnings
Reftable backend adds check for upper limit of log's update_index.
* kn/reftable-writer-log-write-verify:
reftable/writer: ensure valid range for log's update_index
"git bundle create" with an annotated tag on the positive end of
the revision range had a workaround code for older limitation in
the revision walker, which has become unnecessary.
* tc/bundle-with-tag-remove-workaround:
bundle: remove unneeded code
"git fetch" honors "remote.<remote>.followRemoteHEAD" settings to
tweak the remote-tracking HEAD in "refs/remotes/<remote>/HEAD".
* bf/fetch-set-head-config:
remote set-head: set followRemoteHEAD to "warn" if "always"
fetch set_head: add warn-if-not-$branch option
fetch set_head: move warn advice into advise_if_enabled
fetch: add configuration for set_head behaviour
"git fetch" from a configured remote learned to update a missing
remote-tracking HEAD but it asked the remote about their HEAD even
when it did not need to, which has been corrected. Incidentally,
this also corrects "git fetch --tags $URL" which was broken by the
new feature in an unspecified way.
* jc/set-head-symref-fix:
fetch: do not ask for HEAD unnecessarily
When "git fetch $remote" notices that refs/remotes/$remote/HEAD is
missing and discovers what branch the other side points with its
HEAD, refs/remotes/$remote/HEAD is updated to point to it.
* bf/set-head-symref:
fetch set_head: handle mirrored bare repositories
fetch: set remote/HEAD if it does not exist
refs: add create_only option to refs_update_symref_extended
refs: add TRANSACTION_CREATE_EXISTS error
remote set-head: better output for --auto
remote set-head: refactor for readability
refs: atomically record overwritten ref in update_symref
refs: standardize output of refs_read_symbolic_ref
t/t5505-remote: test failure of set-head
t/t5505-remote: set default branch to main
The `git refs migrate` command was introduced in
25a0023f28 (builtin/refs: new command to migrate ref storage formats,
2024-06-06) to support migrating from one reference backend to another.
One limitation of the command was that it didn't support migrating
repositories which contained reflogs. A previous commit, added support
for adding reflog updates in ref transactions. Using the added
functionality bake in reflog support for `git refs migrate`.
To ensure that the order of the reflogs is maintained during the
migration, we add the index for each reflog update as we iterate over
the reflogs from the old reference backend. This is to ensure that the
order is maintained in the new backend.
Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `git log` command already offers support for including diffs for
merges, via the `--diff-merges=<format>` option.
Let's add corresponding support for `git range-diff`, too. This makes it
more convenient to spot differences between commit ranges that contain
merges.
This is especially true in scenarios with non-trivial merges, i.e.
merges introducing changes other than, or in addition to, what merge ORT
would have produced. Merging a topic branch that changes a function
signature into a branch that added a caller of that function, for
example, would require the merge commit itself to adjust that caller to
the modified signature.
In my code reviews, I found the `--diff-merges=remerge` option
particularly useful.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Build procedure update plus introduction of Meson based builds.
* ps/build: (24 commits)
Introduce support for the Meson build system
Documentation: add comparison of build systems
t: allow overriding build dir
t: better support for out-of-tree builds
Documentation: extract script to generate a list of mergetools
Documentation: teach "cmd-list.perl" about out-of-tree builds
Documentation: allow sourcing generated includes from separate dir
Makefile: simplify building of templates
Makefile: write absolute program path into bin-wrappers
Makefile: allow "bin-wrappers/" directory to exist
Makefile: refactor generators to be PWD-independent
Makefile: extract script to generate gitweb.js
Makefile: extract script to generate gitweb.cgi
Makefile: extract script to massage Python scripts
Makefile: extract script to massage Shell scripts
Makefile: use "generate-perl.sh" to massage Perl library
Makefile: extract script to massage Perl scripts
Makefile: consistently use PERL_PATH
Makefile: generate doc versions via GIT-VERSION-GEN
Makefile: generate "git.rc" via GIT-VERSION-GEN
...
The syntax ":/<text>" to name the latest commit with the matching
text was broken with a recent change, which has been corrected.
* ps/commit-with-message-syntax-fix:
object-name: fix reversed ordering with ":/<text>" revisions
The advice messages now tell the newer 'git config set' command to
set the advice.token configuration variable to squelch a message.
* bf/explicit-config-set-in-advice-messages:
advice: suggest using subcommand "git config set"
"git tag" has been taught to refuse to create refs/tags/HEAD
as such a tag will be confusing in the context of UI provided by
the Git Porcelain commands.
* jc/forbid-head-as-tagname:
tag: "git tag" refuses to use HEAD as a tagname
t5604: do not expect that HEAD can be a valid tagname
refs: drop strbuf_ prefix from helpers
refs: move ref name helpers around
"git describe" optimization.
* jk/describe-perf:
describe: split "found all tags" and max_candidates logic
describe: stop traversing when we run out of names
describe: stop digging for max_candidates+1
t/perf: add tests for git-describe
t6120: demonstrate weakness in disjoint-root handling
Yet another "pass the repository through the callchain" topic.
* kn/midx-wo-the-repository:
midx: inline the `MIDX_MIN_SIZE` definition
midx: pass down `hash_algo` to functions using global variables
midx: pass `repository` to `load_multi_pack_index`
midx: cleanup internal usage of `the_repository` and `the_hash_algo`
midx-write: pass down repository to `write_midx_file[_only]`
write-midx: add repository field to `write_midx_context`
midx-write: use `revs->repo` inside `read_refs_snapshot`
midx-write: pass down repository to static functions
packfile.c: remove unnecessary prepare_packed_git() call
midx: add repository to `multi_pack_index` struct
config: make `packed_git_(limit|window_size)` non-global variables
config: make `delta_base_cache_limit` a non-global variable
packfile: pass down repository to `for_each_packed_object`
packfile: pass down repository to `has_object[_kept]_pack`
packfile: pass down repository to `odb_pack_name`
packfile: pass `repository` to static function in the file
packfile: use `repository` from `packed_git` directly
packfile: add repository to struct `packed_git`
"git fast-import" learned to reject paths with ".." and "." as
their components to avoid creating invalid tree objects.
* en/fast-import-verify-path:
t9300: test verification of renamed paths
fast-import: disallow more path components
fast-import: disallow "." and ".." path components
"git bundle --unbundle" and "git clone" running on a bundle file
both learned to trigger fsck over the new objects with configurable
fck check levels.
* jt/bundle-fsck:
transport: propagate fsck configuration during bundle fetch
fetch-pack: split out fsck config parsing
bundle: support fsck message configuration
bundle: add bundle verification options type
To show a remerge diff, the merge needs to be recreated. For that to
work, the merge base(s) need to be found, which means that the commits'
parents have to be traversed until common ancestors are found (if any).
However, one optimization that hails all the way back to cb115748ec
(Some more memory leak avoidance, 2006-06-17) is to release the commit's
list of parents immediately after showing it _and to set that parent
list to `NULL`_. This can break the merge base computation.
This problem is most obvious when traversing the commits in reverse: In
that instance, if a parent of a merge commit has been shown as part of
the `git log` command, by the time the merge commit's diff needs to be
computed, that parent commit's list of parent commits will have been set
to `NULL` and as a result no merge base will be found (even if one
should be found).
Traversing commits in reverse is far from the only circumstance in which
this problem occurs, though. There are many avenues to traversing at
least one commit in the revision walk that will later be part of a merge
base computation, for example when not even walking any revisions in
`git show <merge1> <merge2>` where `<merge1>` is part of the commit
graph between the parents of `<merge2>`.
Another way to force a scenario where a commit is traversed before it
has to be traversed again as part of a merge base computation is to
start with two revisions (where the first one is reachable from the
second but not in a first-parent ancestry) and show the commit log with
`--topo-order` and `--first-parent`.
Let's fix this by special-casing the `remerge_diff` mode, similar to
what we did with reflogs in f35650dff6 (log: do not free parents when
walking reflog, 2017-07-07).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our unit tests that don't yet use the clar unit testing framework ignore
any option that they do not understand. It is thus fine to just pass
test options we set up globally to those unit tests as they are simply
ignored. This makes our life easier because we don't have to special
case those options with Meson, where test options are set up globally
via `meson test --test-args=`.
But our clar-based unit testing framework is way stricter here and will
fail in case it is passed an unknown option. Stub out these options with
no-ops to make our life a bit easier.
Note that this also requires us to remove the `-x` short option for
`--exclude`. This is because `-x` has another meaning in our integration
tests, as it enables shell tracing. I doubt there are a lot of people
out there using it as we only got a small hand full of clar tests in the
first place. So better change it now so that we can in the long run
improve compatibility between the two different test drivers.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Both t9835 and t9836 exercise git-p4, but one exercises Python 2 whereas
the other one uses Python 3. These tests do not exercise "git p4", but
instead they use "git p4.py". This calls the unbuilt version of
"git-p4.py" that still has the "#!/usr/bin/env python" shebang, which
allows the test to modify which Python version comes first in $PATH,
making it possible to force a Python version.
But "git-p4.py" is not in our PATH during out-of-tree builds, and thus
we cannot locate "git-p4.py". The tests thus break with CMake and Meson.
Fix this by instead manually setting up script wrappers that invoke the
respective Python interpreter directly.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the preceding commit, we have introduced consistency checks to Meson
to detect any discrepancies with missing or extraneous tests in its
build instructions. These checks only get executed in Meson though, so
any users of our Makefiles wouldn't be alerted of the fact that they
have to modify the Meson build instructions in case they add or remove
any tests.
Add a comparable test target to our Makefile to plug this gap.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
