According to git bisect, this got broken in the following commit: commit 1819ad327b7a1f19540a819813b70a0e8a7f798f Author: Diomidis Spinellis <dds@xxxxxxx> Date: Fri Aug 26 11:58:15 2022 +0300 grep: fix multibyte regex handling under macOS The commit 29de20504e (Makefile: fix default regex settings on Darwin, 2013-05-11) fixed t0070-fundamental.sh under Darwin (macOS) by adopting Git's regex library. However, this library is compiled with NO_MBSUPPORT, which causes git-grep to work incorrectly on multibyte (e.g. UTF-8) files. Current macOS versions pass t0070-fundamental.sh with the native macOS regex library, which also supports multibyte characters. Adjust the Makefile to use the native regex library, and call setlocale(3) to set CTYPE according to the user's preference. The setlocale call is required on all platforms, but in platforms supporting gettext(3), setlocale was called as a side-effect of initializing gettext. Therefore, move the CTYPE setlocale call from gettext.c to common-main.c and the corresponding locale.h include into git-compat-util.h. Thanks to the global initialization of CTYPE setlocale, the test-tool regex command now works correctly with supported multibyte regexes, and is used to set the MB_REGEX test prerequisite by assessing a platform's support for them. Signed-off-by: Diomidis Spinellis <dds@xxxxxxx> Signed-off-by: Junio C Hamano <gitster@xxxxxxxxx> Makefile | 2 +- common-main.c | 1 + gettext.c | 2 -- git-compat-util.h | 1 + t/t7810-grep.sh | 15 +++++++++++++++ 5 files changed, 18 insertions(+), 3 deletions(-)