Re: [PATCH v2] libbpf bpf_helpers: Use __builtin_offsetof for offsetof

From: Alexei Starovoitov
Date: Tue Jul 21 2020 - 15:26:56 EST


On Sun, Jul 19, 2020 at 11:21 PM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Sun, Jul 19, 2020 at 11:18 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
> >
> > The non-builtin route for offsetof has a dependency on size_t from
> > stdlib.h/stdint.h that is undeclared and may break targets.
> > The offsetof macro in bpf_helpers may disable the same macro in other
> > headers that have a #ifdef offsetof guard. Rather than add additional
> > dependencies improve the offsetof macro declared here to use the
> > builtin that is available since llvm 3.7 (the first with a BPF backend).
> >
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > ---
>
> Acked-by: Andrii Nakryiko <andriin@xxxxxx>

Applied. Thanks