git/Documentation/RelNotes/2.39.0.txt

Git v2.39 Release Notes
=======================

UI, Workflows & Features
------------------------

 * "git grep" learned to expand the sparse-index more lazily and on
   demand in a sparse checkout.

 * By default, use of fsmonitor on a repository on networked
   filesystem is disabled. Add knobs to make it workable on macOS.

 * After checking out a "branch" that is a symbolic-ref that points at
   another branch, "git symbolic-ref HEAD" reports the underlying
   branch, not the symbolic-ref the user gave checkout as argument.
   The command learned the "--no-recurse" option to stop after
   dereferencing a symbolic-ref only once.

 * "git branch --edit-description @{-1}" is now a way to edit branch
   description of the branch you were on before switching to the
   current branch.


Performance, Internal Implementation, Development Support etc.
--------------------------------------------------------------

 * With a bit of header twiddling, use the native regexp library on
   macOS instead of the compat/ one.

 * Prepare for GNU [ef]grep that throw warning of their uses.

 * Sources related to fuzz testing have been moved down to their own
   directory.

 * Most credential helpers ignored unknown entries in a credential
   description, but a few died upon seeing them.  The latter were
   taught to ignore them, too

 * "scalar unregister" in a repository that is already been
   unregistered reported an error.

 * Remove error detection from a function that fetches from promisor
   remotes, and make it die when such a fetch fails to bring all the
   requested objects, to give an early failure to various operations.

 * Update CodingGuidelines to clarify what features to use and avoid
   in C99.

 * Avoid false-positive from LSan whose assumption may be broken with
   higher optimization levels.

 * Enable address and undefined sanitizer tasks at GitHub Actions CI.

 * More UNUSED annotation to help using -Wunused option with the
   compiler.
   (merge 4b992f0a24 jk/unused-anno-more later to maint).


Fixes since v2.38
-----------------

 * The codepath that reads from the index v4 had unaligned memory
   accesses, which has been corrected.

 * Fix messages incorrectly marked for translation.

 * "git fsck" failed to release contents of tree objects already used
   from the memory, which has been fixed.

 * "git clone" did not like to see the "--bare" and the "--origin"
   options used together without a good reason.

 * "git remote rename" failed to rename a remote without fetch
   refspec, which has been corrected.

 * Documentation on various Boolean GIT_* environment variables have
   been clarified.

 * "git rebase -i" can mistakenly attempt to apply a fixup to a commit
   itself, which has been corrected.

 * "git multi-pack-index repack/expire" used to repack unreachable
   cruft into a new pack, which have been corrected.

 * In read-only repositories, "git merge-tree" tried to come up with a
   merge result tree object, which it failed (which is not wrong) and
   led to a segfault (which is bad), which has been corrected.

 * Force C locale while running tests around httpd to make sure we can
   find expected error messages in the log.

 * Fix a logic in "mailinfo -b" that miscomputed the length of a
   substring, which lead to an out-of-bounds access.

 * The codepath to sign learned to report errors when it fails to read
   from "ssh-keygen".

 * Code clean-up that results in plugging a leak.

 * "GIT_EDITOR=: git branch --edit-description" resulted in failure,
   which has been corrected.

 * The code to clean temporary object directories (used for
   quarantine) tried to remove them inside its signal handler, which
   was a no-no.

 * Update comment in the Makefile about the RUNTIME_PREFIX config knob.

 * Clarify that "the sentence after <area>: prefix does not begin with
   a capital letter" rule applies only to the commit title.

 * "git branch --edit-description" on an unborh branch misleadingly
   said that no such branch exists, which has been corrected.

 * Work around older clang that warns against C99 zero initialization
   syntax for struct.

 * Giving "--invert-grep" and "--all-match" without "--grep" to the
   "git log" command resulted in an attempt to access grep pattern
   expression structure that has not been allocated, which has been
   corrected.
   (merge db84376f98 ab/grep-simplify-extended-expression later to maint).

 * "git diff rev^!" did not show combined diff to go to the rev from
   its parents.
   (merge a79c6b6081 rs/diff-caret-bang-with-parents later to maint).

 * Allow configuration files in "protected" scopes to include other
   configuration files.
   (merge ecec57b3c9 gc/bare-repo-discovery later to maint).

 * Give a bit more diversity to macOS CI by using sha1dc in one of the
   jobs (the other one tests Apple Common Crypto).
   (merge 1ad5c3df35 jc/ci-osx-with-sha1dc later to maint).

 * A bugfix with tracing support in midx codepath
   (merge e9c3839944 tb/midx-bitmap-selection-fix later to maint).

 * When geometric repacking feature is in use together with the
   --pack-kept-objects option, we lost packs marked with .keep files.
   (merge 197443e80a tb/save-keep-pack-during-geometric-repack later to maint).

 * Move a global variable added as a hack during regression fixes to
   its proper place in the API.
   (merge 0b0ab95f17 ab/run-hook-api-cleanup later to maint).

 * Update to build procedure with VS using CMake/CTest.
   (merge c858750b41 js/cmake-updates later to maint).

 * The short-help text shown by "git cmd -h" and the synopsis text
   shown at the beginning of "git help cmd" have been made more
   consistent.

 * When creating a multi-pack bitmap, remove per-pack bitmap files
   unconditionally as they will never be consulted.
   (merge 55d902cd61 tb/remove-unused-pack-bitmap later to maint).

 * Fix a longstanding syntax error in Git.pm error codepath.

 * "git diff --stat" etc. were invented back when everything was ASCII
   and strlen() was a way to measure the display width of a string;
   adjust them to compute the display width assuming UTF-8 pathnames.
   (merge ce8529b2bb tb/diffstat-with-utf8-strwidth later to maint).

 * Other code cleanup, docfix, build fix, etc.
   (merge 413bc6d20a ds/cmd-main-reorder later to maint).
   (merge 8d2863e4ed nw/t1002-cleanup later to maint).