Hi Nguyễn, On Wed, Apr 18, 2018 at 7:53 AM, Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx> wrote: > The function compute_rev_name() can return NULL sometimes (e.g. right > after 'submodule init'). The current code makes 'submodule status' > print this: > > 19d97bf5af05312267c2e874ee6bcf584d9e9681 sha1collisiondetection ((null)) > > This ugly 'null' adds no value to the user using this command. More > importantly printf() on some platform can't handle NULL as a string > and will crash instead of printing '(null)'. > > Check for this and skip printing this part (the alternative is > printing '(n/a)' or something but I think that is just noise). This patch restores the behavior from before a9f8a37584 (submodule: port submodule subcommand 'status' from shell to C, 2017-10-06), so this is the right way to go instead of the alternatives you considered. Thanks! Reviewed-by: Stefan Beller <sbeller@xxxxxxxxxx> > Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx> > --- > builtin/submodule--helper.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c > index a404df3ea4..4dc7d7d29f 100644 > --- a/builtin/submodule--helper.c > +++ b/builtin/submodule--helper.c > @@ -596,8 +596,12 @@ static void print_status(unsigned int flags, char state, const char *path, > > printf("%c%s %s", state, oid_to_hex(oid), displaypath); > > - if (state == ' ' || state == '+') > - printf(" (%s)", compute_rev_name(path, oid_to_hex(oid))); > + if (state == ' ' || state == '+') { > + const char *name = compute_rev_name(path, oid_to_hex(oid)); > + > + if (name) > + printf(" (%s)", name); > + } > > printf("\n"); > } > -- > 2.17.0.367.g5dd2e386c3 >