[FFmpeg-devel] [PATCH 2/8] libutvideodec: Replace a silly stay constant

[Reimar Döffinger]

On Mon, Nov 07, 2011 at 12:20:23PM -0500, Derek Buitenhuis wrote:
> Replace a silly '4*4' with a proper sizeof() call,
> for setting the extradata size.
> 
> Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
> ---
>  libavcodec/libutvideo.cpp |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/libavcodec/libutvideo.cpp b/libavcodec/libutvideo.cpp
> index fa1bcc5..43b5209 100644
> --- a/libavcodec/libutvideo.cpp
> +++ b/libavcodec/libutvideo.cpp
> @@ -53,7 +53,7 @@ static av_cold int utvideo_decode_init(AVCodecContext *avctx)
>      UtVideoExtra info;
>      int format;
>  
> -    if(avctx->extradata_size != 4*4)
> +    if(avctx->extradata_size != sizeof(UtVideoExtra))

That is no good, there is no guarantee how exactly the compiler
lays it out and thus sizeof(UtVideoExtra) could also be e.g.
32 (on an hypothetical architecture that can only read 8 byte
aligned ints).