It's a false positive. We use -1 to index an array, but it's not actually used. This patch will make the "GCC UndefinedBehaviorSanitizer" happy.
Found by: checkasm-hevc_pel in https://fate.ffmpeg.org/report.cgi?time=20240211011905&slot=x86_64-archlinux-gcc-ubsan Reported-by: James Almer <jamr...@gmail.com> --- libavcodec/hevcdsp_template.c | 6 +++--- libavcodec/x86/hevcdsp_init.c | 6 +++--- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/libavcodec/hevcdsp_template.c b/libavcodec/hevcdsp_template.c index 9b48bdf08e..a4b8901e5d 100644 --- a/libavcodec/hevcdsp_template.c +++ b/libavcodec/hevcdsp_template.c @@ -301,9 +301,9 @@ IDCT_DC(32) // //////////////////////////////////////////////////////////////////////////////// #define ff_hevc_pel_filters ff_hevc_qpel_filters -#define DECL_HV_FILTER(f) \ - const uint8_t *hf = ff_hevc_ ## f ## _filters[mx - 1]; \ - const uint8_t *vf = ff_hevc_ ## f ## _filters[my - 1]; +#define DECL_HV_FILTER(f) \ + const uint8_t *hf = mx ? ff_hevc_ ## f ## _filters[mx - 1] : NULL; \ + const uint8_t *vf = my ? ff_hevc_ ## f ## _filters[my - 1] : NULL; #define FW_PUT(p, f, t) \ static void FUNC(put_hevc_## f)(int16_t *dst, const uint8_t *src, ptrdiff_t srcstride, int height, \ diff --git a/libavcodec/x86/hevcdsp_init.c b/libavcodec/x86/hevcdsp_init.c index 31e81eb11f..e0f65177c4 100644 --- a/libavcodec/x86/hevcdsp_init.c +++ b/libavcodec/x86/hevcdsp_init.c @@ -87,9 +87,9 @@ IDCT_FUNCS(avx) #define ff_hevc_pel_filters ff_hevc_qpel_filters -#define DECL_HV_FILTER(f) \ - const uint8_t *hf = ff_hevc_ ## f ## _filters[mx - 1]; \ - const uint8_t *vf = ff_hevc_ ## f ## _filters[my - 1]; +#define DECL_HV_FILTER(f) \ + const uint8_t *hf = mx ? ff_hevc_ ## f ## _filters[mx - 1] : NULL; \ + const uint8_t *vf = my ? ff_hevc_ ## f ## _filters[my - 1] : NULL; \ #define FW_PUT(p, a, b, depth, opt) \ void ff_hevc_put_hevc_ ## a ## _ ## depth ## _##opt(int16_t *dst, const uint8_t *src, ptrdiff_t srcstride, \ -- 2.25.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
