[U-Boot] [PATCH v3 2/3] dfu: ram support
Afzal Mohammed
afzal.mohd.ma at gmail.com
Fri Sep 13 19:05:45 CEST 2013
Hi Gerhard, Marek,
On Fri, Sep 13, 2013 at 05:37:36PM +0200, Gerhard Sittig wrote:
> On Fri, Sep 13, 2013 at 15:51 +0200, Marek Vasut wrote:
> > > + dfu->data.ram.size = simple_strtoul(++s, &s, 16);
> >
> > This ++s, &s is quite crazy ;-)
> Actually it's not just a neat trick, but instead it's not
> guaranteed to work. It's an inviation for problems that you
> don't need.
>
> The order in which arguments for the call get evaluated isn't
> specified, so behaviour is uncertain here. Read: the
> construction happens to work by coincidence for individual
> setups, but isn't correct and need not work elsewhere, and may
> break in arbitrary ways at any occasion, and then is hard to
> track down since things may "seem to work" often enough or the
> bug won't show up when you are diagnosing the problem.
>
> The code needs to get fixed before getting picked up. Doing the
> increment in a separate instruction is cheap and simple, the
> terse form is wrong.
Yes wrong me, I realize that result is compiler dependent and not
guaranteed to work always, v4 posted taking care of the above.
Regards
Afzal
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