From 415f012359364a77e8394436f222b74a8641a3ee Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Mon, 30 May 2022 18:26:40 +0200 Subject: [PATCH] avcodec/ffv1enc: Fix undefined left shifts of negative numbers Maybe this fixes the FPE encountered here: https://fate.ffmpeg.org/report.cgi?slot=alpha-debian-qemu-gcc-4.7&time=20220530144951 Reviewed-by: Michael Niedermayer Signed-off-by: Andreas Rheinhardt --- libavcodec/ffv1enc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/ffv1enc.c b/libavcodec/ffv1enc.c index 311f377b1e..9849082e44 100644 --- a/libavcodec/ffv1enc.c +++ b/libavcodec/ffv1enc.c @@ -143,7 +143,7 @@ static void find_best_state(uint8_t best_state[256][256], uint32_t l2tab[256]; for (i = 1; i < 256; i++) - l2tab[i] = log2(i / 256.0) * ((-1<<31) / 8); + l2tab[i] = -log2(i / 256.0) * ((1U << 31) / 8); for (i = 0; i < 256; i++) { uint64_t best_len[256];