[U-Boot] [PATCH] net: Always build the string_to_enetaddr() helper

[Simon Goldschmidt]

Joe Hershberger <joe.hershberger at ni.com> schrieb am Sa., 14. Sep. 2019,
20:46:

> On Sat, Sep 14, 2019 at 1:32 PM Tom Rini <trini at konsulko.com> wrote:
> >
> > On Sat, Sep 14, 2019 at 04:05:44PM +0200, Ondřej Jirman wrote:
> > > Hi,
> > >
> > > On Fri, Sep 13, 2019 at 07:40:22PM -0500, Joe Hershberger wrote:
> > > > Part of the env cleanup moved this out of the environment code and
> into
> > > > the net code. However, this helper is sometimes needed even when the
> net
> > > > stack isn't included.
> > > >
> > > > Move the helper to lib/net_utils.c like it's similarly-purposed
> > > > string_to_ip(). Also rename the moved function to similar naming.
> > > >
> > > > Signed-off-by: Joe Hershberger <joe.hershberger at ni.com>
> > > > Reported-by: Ondrej Jirman <megous at megous.com>
> > >
> > > I've tested the patch and it works, but I'be found other related
> issue, where
> > > u-boot thinks %pM will format a MAC address string, but it does just
> > > print out the pointer due to relevant functions being gated by
> CONFIG_CMD_NET
> > > guard in lib/vsprintf.c.
> > >
> > > The gating should probably be done so that it panics/halts the u-boot
> if gated
> > > pointer flags are used by u-boot code, because that will clearly be
> incorrect,
> > > without calling code ever knowing. This way the user will know that
> something
> > > is wrong and will have to fix the code.
> >
> > I'm not in favor of panic because of calling an unimplemented print
> > format character.  I guess we'll need to see what the size increase is
> > on un-guarding these formats and go from there.
>
> I'll look into it. I'm also not in favor of a panic.
>

In lwIP, we're using macros for such format characters. Would it work to do
that here and make the compiler complain about an undefined symbol of the
macro for this extended format character isn't defined?

Regards,
Simon