On Tue, Jul 30, 2024 at 10:56:04AM -0700, Junio C Hamano wrote:

One wrong assumption was that the function might yield NULL when
there is no interpolation.  This led to the use of an extra "check"
variable, conditionally holding either the interpolated or the
original string.  The assumption was with us since 8959555c
(setup_git_directory(): add an owner check for the top-level
directory, 2022-03-02) originally introduced the safe.directory
feature.

Another wrong assumption was that the function might yield the same
pointer as the input when there is no interpolation.  This led to a
conditional free'ing of the interpolated copy, that the conditional
never skipped, as we always received an allocated string.

Yup. Good eyes on seeing that second one. Both look correct to me from
double-checking git_config_pathname(), and the patch itself looks good.

-Peff