Possible regression in arm/io.h

[Will Deacon]

On Thu, Nov 22, 2012 at 07:57:35AM +0000, Artem Bityutskiy wrote:
> On Wed, 2012-10-24 at 16:27 +0100, Will Deacon wrote:
> > On Wed, Oct 24, 2012 at 04:04:46PM +0100, Bastian Hecht wrote:
> > > >> > Ok, I'll have a look at the impact of moving exclusively to "Q" when I get a
> > > >> > chance. Which toolchain are you using?
> > > >>
> > > >> gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
> > > >> For a more verbose info take a look at the bug report link.
> > > >
> > > > Ok, thanks. One other thing you could try while I try to find a copy of that
> > > > toolchain is changing the "+" modifier to an "=", like I proposed in this
> > > > version of the patch:
> > > 
> > > So if alter it to fit to your patch scheme the result is:
> > 
> > Sorry, the change wasn't as trivial as I thought -- you have to reorder the
> > constraints because an output becomes an input for the load accessors. I
> > tried it myself and it doesn't fix the issue (I can reproduce it now).
> 
> Any progress with this? Do we end up with gcc 4.6+ - uncompilable MTD
> drivers in 3.7?

I fixed it in 7629a9f661f7 ("ARM: 7567/1: io: avoid GCC's offsettable
addressing modes for halfword accesses").

Will