No, this is not about a quiz on regexp compatibility between Perl
and sed.

Back when cdbdc6b (t: refactor tests depending on Perl substitution
operator, 2025-04-03) rewrote many uses of perl with sed, the general
pattern of the original scripts were

    chmod +w some_read_only_file &&
    perl -p -e "regexp to munge" some_read_only_file >some_tmp &&
    mv some_tmp some_read_only_file

persumably because the author knew that replacing some_read_only_file
with "mv" at the last step would not work without "mv -f" in some
environments (GNU seems to succeed without giving any prompt when
not running interactively, which is what happens when running t/
scripts).  Replacing perl with sed would be fine as long as sed with
updated regexp does the equivalent munging.

But one place used to use a different construct in the original:

    perl -i.bak -p -e "regexp to munge" some_read_only_file

With _no_ temporary file or "mv", "perl -i" allows you to replace a
read-only file in place.

When we replaced the use of "perl" with "sed" in the said commit,
however, because "sed -i" is not portable, we rewrote that in-place
replacement to

    sed "regexp to munge" some_read_only_file >some_tmp &&
    mv some_tmp some_read_only_file

Again, unfortunately that does not work in some environment, without
"mv -f".

We could run "mv -f" here, but we would then need to remove "chmod
+w" and have them use "mv -f" instead at all places that were
touched cdbdc6b (t: refactor tests depending on Perl substitution
operator, 2025-04-03) to be consistent (and more concise).

For now, let's make it consistent in the other direction by mimick
the other places that made the target read-write before moving.

Speaking of portability, the outcome of using "sed" on non-text
files is unspecified, so the entire exercise of cdbdc6b may have
needed to be reverted if people still used ancient version of
"standard compliant" sed that barfs on non-text files, but these
days we may be able to get away with "BSDs and GNU seem OK with it"
;-)  But one fix at a time.

Reported-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Compiling/linking 82e79c6 on an older MacOs machine (like Xcode
14.3.1, the last version of 14.x series) leads to this:

    Undefined symbols for architecture x86_64:
      "_false_but_the_compiler_does_not_know_it_", referenced from:
	  _start_command in libgit.a(run-command.o)

The linker fails to pick up compiler-tricks/not-constant.o that
defines the needed false_but_the_compiler_does_not_know_it_ symbol,
which is the only thing defined in that object file, from the
libgit.a archive.

Initializing the variable explicitly to 0 works around the linker
bug; the symbol type changes from 'C' to 'S' and is picked up by the
linker.

Xcode 15 introduces a new linker, which seems to fix the bug, making
the workaround here unnecessary, and Apple requires to build with
Xcode 16 or later in order to upload to their App Store Connect
since April 24, 2025, but not everybody is expected to upgrade their
toolchain immediately.

Helped-by: Koji Nakamaru <koji.nakamaru@gree.net>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The parameters of `cmd_gc()` aren't indented properly. Fix this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

We use a couple of global variables to assemble command line arguments
for subprocesses we execute in git-gc(1). All of these variables except
the one for git-repack(1) are only used in a single place though, so
they don't really add anything but confusion.

Remove those variables.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

In a subsequent commit we will introduce a new "worktree-prune" task for
git-maintenance(1). To prepare for this, refactor the code that spawns
`git worktree prune` into a separate function.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

While git-gc(1) knows to prune stale worktrees, git-maintenance(1) does
not yet have a task for this cleanup. Introduce a new "worktree-prune"
task to plug this gap.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

In a subsequent commit we are going to introduce a new "rerere-gc" task
for git-maintenance(1). To prepare for this, refactor the code that
spawns `git rerere gc` into a separate function.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

While git-gc(1) knows to garbage collect the rerere cache,
git-maintenance(1) does not yet have a task for this cleanup. Introduce
a new "rerere-gc" task to plug this gap.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Some distros, notably Fedora, want to install non-core Perl libraries
into specific directory, namely /usr/share/perl5/vendor_perl.

The Makefile build system allows this by overriding perllibdir variable,
let's make meson works on par with our Makefile.

Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The fallback implementation of open_nofollow() depended on
open("symlink", O_NOFOLLOW) to set errno to ELOOP, but a few BSD
derived systems use different errno, which has been worked around.

* cf/wrapper-bsd-eloop:
  wrapper: NetBSD gives EFTYPE and FreeBSD gives EMFILE where POSIX uses ELOOP

Make repository clean-up tasks "gc" can do available to "git
maintenance" front-end.

* ps/maintenance-missing-tasks:
  builtin/maintenance: introduce "rerere-gc" task
  builtin/gc: move rerere garbage collection into separate function
  builtin/maintenance: introduce "worktree-prune" task
  builtin/gc: move pruning of worktrees into a separate function
  builtin/gc: remove global variables where it is trivial to do
  builtin/gc: fix indentation of `cmd_gc()` parameters

Meson-based build framework update.

* dd/meson-perl-custom-path:
  meson: allow customize perl installation path

Test fix.

* jc/t6011-mv-ro-fix:
  t6011: fix misconversion from perl to sed

Workaround for older macOS ld.

* tb/macos-false-but-the-compiler-does-not-know-it-fix:
  intialize false_but_the_compiler_does_not_know_it_

Signed-off-by: Junio C Hamano <gitster@pobox.com>