[FFmpeg-cvslog] dca: fix signed overflow in shift

[Mans Rullgard]

ffmpeg | branch: release/0.8 | Mans Rullgard <mans at mansr.com> | Sat Oct  8 13:49:42 2011 +0100| [58afe6061adf61c17a876ce22b4dae03d0c0299a] | committer: Reinhard Tartler

dca: fix signed overflow in shift

Signed-off-by: Mans Rullgard <mans at mansr.com>
(cherry picked from commit 559c244d42be7a02c23976216b47fd63b80d6c7f)

Signed-off-by: Anton Khirnov <anton at khirnov.net>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=58afe6061adf61c17a876ce22b4dae03d0c0299a
---

 libavcodec/dca.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/libavcodec/dca.c b/libavcodec/dca.c
index fad6bce..19d24c5 100644
--- a/libavcodec/dca.c
+++ b/libavcodec/dca.c
@@ -902,7 +902,8 @@ static void qmf_32_subbands(DCAContext * s, int chans,
     for (subindex = 0; subindex < 8; subindex++) {
         /* Load in one sample from each subband and clear inactive subbands */
         for (i = 0; i < sb_act; i++){
-            uint32_t v = AV_RN32A(&samples_in[i][subindex]) ^ ((i-1)&2)<<30;
+            unsigned sign = (i - 1) & 2;
+            uint32_t v = AV_RN32A(&samples_in[i][subindex]) ^ sign << 30;
             AV_WN32A(&s->raXin[i], v);
         }
         for (; i < 32; i++)