[FFmpeg-cvslog] arm: fix use of uninitialised value in ff_fft_fixed_init_arm()

[Mans Rullgard]

ffmpeg | branch: master | Mans Rullgard <mans at mansr.com> | Thu Dec  6 23:51:01 2012 +0000| [92dad6687f59a6e599834218626e524eb8a5bdae] | committer: Mans Rullgard

arm: fix use of uninitialised value in ff_fft_fixed_init_arm()

When initialising an FFTContext for a plain FFT, mdct_bits is not set
and can contain a garbage value.  Since nbits is always valid and for
MDCT operation is mdct_bits - 2 checking this instead avoids using an
uninitialised value while having the same effect.

Signed-off-by: Mans Rullgard <mans at mansr.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=92dad6687f59a6e599834218626e524eb8a5bdae
---

 libavcodec/arm/fft_fixed_init_arm.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/arm/fft_fixed_init_arm.c b/libavcodec/arm/fft_fixed_init_arm.c
index 5601ba1..50532f2 100644
--- a/libavcodec/arm/fft_fixed_init_arm.c
+++ b/libavcodec/arm/fft_fixed_init_arm.c
@@ -36,7 +36,7 @@ av_cold void ff_fft_fixed_init_arm(FFTContext *s)
         s->fft_calc        = ff_fft_fixed_calc_neon;
 
 #if CONFIG_MDCT
-        if (!s->inverse && s->mdct_bits >= 5) {
+        if (!s->inverse && s->nbits >= 3) {
             s->mdct_permutation = FF_MDCT_PERM_INTERLEAVE;
             s->mdct_calc        = ff_mdct_fixed_calc_neon;
             s->mdct_calcw       = ff_mdct_fixed_calcw_neon;