[FFmpeg-devel] [PATCH v2] avcodec/tscc: fix the warning: assigning to 'Bytef *' (aka 'unsigned char *') from 'const uint8_t *

[Carl Eugen Hoyos]

Am Do., 5. Sept. 2019 um 00:45 Uhr schrieb <lance.lmwang at gmail.com>:
>
> From: Limin Wang <lance.lmwang at gmail.com>
>
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
>  libavcodec/tscc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/libavcodec/tscc.c b/libavcodec/tscc.c
> index 6d03081..b0dbef4 100644
> --- a/libavcodec/tscc.c
> +++ b/libavcodec/tscc.c
> @@ -88,7 +88,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
>          av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
>          return AVERROR_UNKNOWN;
>      }
> -    c->zstream.next_in   = buf;
> +    c->zstream.next_in   = (uint8_t*)buf;

Iirc, the warning also happens when compiling for android and the reason
is that their zlib header is different / old and therefore doesn't mark the
input as const (as the zlib header does on different systems here, both
new and old). I therefore believe this line should not be changed.

If it is changed, the commit message should first state was is done
("cast a pointer to avoid a warning") and the actual complete warning
should be part of the commit message.

Carl Eugen

(Checking Android sources seems to show that they have fixed
this issue in more recent versions.)