[FFmpeg-devel] [PATCH] avutils/video_enc_params: remove unnecessary check to fix compile warning

[Anton Khirnov]

Quoting Nuo Mi (2021-02-14 07:26:56)
> This will fix following compile warning:
> 
> libavutil/video_enc_params.c: In function ‘av_video_enc_params_alloc’:                                                                                                                                                                     libavutil/video_enc_params.c:36:19: warning: comparison is always false due to limited range of data type [-Wtype-limits]                                                                                                                       36 |     if (nb_blocks > SIZE_MAX / sizeof(AVVideoBlockParams) ||                                                                                                                                                                               |                   ^
> 
> Suppose a is "nb_blocks > SIZE_MAX / sizeof(AVVideoBlockParams))"
> b is "nb_blocks * sizeof(AVVideoBlockParams) > SIZE_MAX - sizw"
> If a is true, b is true.
> If a is false, the expression depends on b.
> No matter a is true or not, it we only need check b.

Check a is needed to prevent overflow in b.

IMO the warning is bogus and we should consider disabling it.

-- 
Anton Khirnov