[U-Boot] [PATCH v3 5/6] omap4+: Avoid using __attribute__ ((__packed__))

Mike Frysinger vapier at gentoo.org
Thu Feb 23 16:03:34 CET 2012


On Thursday 23 February 2012 09:56:24 Aneesh V wrote:
> On Thursday 23 February 2012 07:51 PM, Tom Rini wrote:
> > On Thu, Feb 23, 2012 at 7:06 AM, Aneesh V<aneesh at ti.com>  wrote:
> >> Avoid using __attribute__ ((__packed__)) unless it's
> >> absolutely necessary. "packed" will remove alignment
> >> requirements for the respective objects and may cause
> >> alignment issues unless alignment is also enforced
> >> using a pragma.
> >> 
> >> Here, these packed attributes were causing alignment
> >> faults in Thumb build.
> > 
> > Why did we pack these to start with?  Otherwise seems fine (and I see
> > the rest of the TI parts don't have this particular packing).
> 
> I think that was to save some space - to make sure that the compiler
> didn't pad the structure to have the u16 fields at word boundary. But
> even without "packed" the complier is not padding it. I checked that
> today, the size of the mux arrays remain the same even after removing
> the "packed". So, I guess the "packed" didn't have any impact.

i don't think so.  see my other reply.
-mike
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