[Ffmpeg-devel] [PATCH]: Too much alignment assumed by H264 decoder

Mike Melanson mike
Thu Dec 22 17:44:58 CET 2005

David S. Miller wrote:
> These uint64_t cast memory operations cause unaligned accesses on
> platforms such as Sparc, there really isn't anything in the
> datastructures to ensure this level of alignment.
> But uint32_t seems to work fine, as the following patch against
> current CVS implements.

	Wait... run that by me again: 8-byte alignment causes crashes but 
4-byte alignment is okay? I hope I don't have to point out that this 
doesn't make much sense. Or are you saying that the compiler you are 
using on Sparc does not support 8-byte alignment and so the data 
structure is being aligned on a random boundary?

	I must contend that if something in FFmpeg is aligned on an 8-byte 
boundary, it it probably that way for a good reason. One such reason is 
SIMD operations.

	-Mike Melanson

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