Re: pandaboard/omap4 support

[Denys Dmytriyenko <denys@ti.com>]

On Wed, Feb 12, 2014 at 03:15:38PM +0100, Richard Röjfors wrote:
> On Wed, Feb 12, 2014 at 3:07 PM, Khem Raj <raj.khem@gmail.com> wrote:
> 
> >
> > On Feb 12, 2014, at 6:03 AM, Richard Röjfors <richard.rojfors@gmail.com>
> > wrote:
> >
> > On Wed, Feb 12, 2014 at 2:52 PM, Khem Raj <raj.khem@gmail.com> wrote:
> >
> >>
> >> what incompatibilities do you see between 4.7 and 4.8 ?
> >>
> >
> > I saw this in the gcc 4.8 changelog:
> > "On ARM, a bug has been fixed in GCC's implementation of the AAPCS rules
> > for the layout of vectors that could lead to wrong code being generated.
> > Vectors larger than 8 bytes in size are now by default aligned to an 8-byte
> > boundary. This is an ABI change: code that makes explicit use of vector
> > types may be incompatible with binary objects built with older versions of
> > GCC. Auto-vectorized code is not affected by this change.”
> >
> >
> > OK. are you seeing this use case here ?
> >
> 
> Nope I've not hit it nor gone through the calls between the blobs and the
> surrounding code.
> 
> I just think it makes sense to compile the blobs with a compiler similar to
> the one provided by oe-core, to avoid the risk...

The biggest problem is not 4.7 vs. 4.8, but rather incompatibilities in ABIs 
and call conventions. E.g. we have switched to hardfp for our products and 
some of our components distributed in binary form are only available in hardfp 
format. And oe-core doesn't use hardfp by default yet...

-- 
Denys