[MPlayer-dev-eng] gcc 2.95 compiler bug

[Diego Biurrun]

Hi!

Looks like our beloved icon of free software compiler technology is
getting blemishes ;-)

I'm 99% positive I identified a compiler bug in gcc 2.95.3/4 related
to H.261 support.  When I play one of the samples from

http://mplayerhq.hu/MPlayer/samples/h261-raw/

I get something like the following output (qcifhall28.p64):

Starting playback...
[h261 @ 0x85ca79c]Bad picture start code
[h261 @ 0x85ca79c]header damaged
Error while decoding frame!
[h261 @ 0x85ca79c]warning: first frame is no keyframe
[ffmpeg] aspect_ratio: 0.000000
VDec: vo config request - 176 x 144 (preferred csp: Planar YV12)
Trying filter chain: vo
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is nan:1 - prescaling to correct movie aspect.
VO Config (176x144->176x-2147483648,flags=0,'MPlayer',0x32315659)
VO: invalid dimensions!
FATAL: Cannot initialize video driver.

And the movie is not played.  This only happens when I compile MPlayer
with gcc 2.95.4, with gcc 3.3.4 it works fine.  Disabling processor
optimizations through --disable-mmx and "-march=pentium -mcpu=pentium"
changes nothing and the problem also happens with a self-compiled gcc
2.95.3, not only with 2.95.4 from my Debian testing system.

Further details in this bug report:

http://bugzilla.mplayerhq.hu/show_bug.cgi?id=128

Diego