Re: [dpdk-dev] [PATCH v2 2/2] bpf: fix convert API can be undefined

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> On Tue, 2 Nov 2021 10:54:59 +0000
> "Ananyev, Konstantin" <konstantin.ananyev@intel.com> wrote:
> 
> > > > rte_bpf_convert() implementation depends on libpcap.
> > > > Right now it is defined only when this library is installed and
> > > > RTE_PORT_PCAP is defined.
> > > > Fix that by providing for such case stub rte_bpf_convert()
> > > > implementation that will always return an error.
> > > > Also move stub for another function (rte_bpf_elf_load) into
> > > > the same place (bpf_stub.c).
> > > >
> > > > Fixes: 2eccf6afbea9 ("bpf: add function to convert classic BPF to DPDK BPF")
> > > >
> > > > Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> > >
> > > Wouldn't it be better to fail compiling a program using unimplemented calls
> > > rather than forcing the user to see a failure later?
> >
> > You mean to keep things as they are right now?
> > That way we'll have to put #ifdef RTE_PORT_PCAP around every call to bpf_convert().
> > Doesn't look like a good thing to me.
> > Also in other places we use similar approach: if HW/SW is not available provide
> > a dummy implementation that will report an error.
> 
> Is there a way to do both, return an error and report a warning in the build?

Sounds like a good idea, will add a warning to meson.build.