From: SZEDER Gábor Date: Fri, 20 Sep 2019 15:40:49 GMT Subject: Re: [PATCH 05/15] name-rev: use sizeof(*ptr) instead of sizeof(type) in allocation Message-ID: <20190920154049.GA32332@szeder.dev> In-Reply-To: On Fri, Sep 20, 2019 at 11:11:02AM -0400, Derrick Stolee wrote: > On 9/19/2019 5:47 PM, SZEDER Gábor wrote: > > Signed-off-by: SZEDER Gábor > > --- > > builtin/name-rev.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/builtin/name-rev.c b/builtin/name-rev.c > > index e406ff8e17..dec2228cc7 100644 > > --- a/builtin/name-rev.c > > +++ b/builtin/name-rev.c > > @@ -98,7 +98,7 @@ static void name_rev(struct commit *commit, > > } > > > > if (name == NULL) { > > - name = xmalloc(sizeof(rev_name)); > > + name = xmalloc(sizeof(*name)); > > Is this our preferred way to use xmalloc()? If so, then > I've been doing it wrong and will correct myself in the > future. I seem to remember that Peff mentioned in a commit message that this is the preferred way, but can't find it at the moment. Anyway, when using 'sizeof(*ptr)' the type is inferred by the compiler, but when using 'sizeof(type)' then we have to make sure that 'type' is indeed the right type. Besides, that 'rev_name' should have been spelled as 'struct rev_name' to begin with.