[MPlayer-dev-eng] MPlayer interrupted by signal 4 in module: decode_video

[Siarhei Siamashka]

On Friday 08 June 2007 01:19, Shapiro, Alex (OTTAWA) wrote:

> My svn MPlayer crushed with the following debugger message: Signal
> received(SIGILL) in Thread mplayer at
> mplayer-checkout-2007-06-01/libavcodec/armv4l/simple_idct_armv6.S:288
> illegal instruction.

Yes, it is indeed illegal instruction for your processor. You got ARMv6
optimizations compiled in while your cpu supports ARMv5TE only.

> / # cat /proc/cpuinfo
> Processor       : ARM926EJ-Sid(wb) rev 3 (v5l)
> BogoMIPS        : 125.76
> Features        : swp half thumb fastmult edsp java

[...]

> MPlayer interrupted by signal 4 in module: decode_video
> - MPlayer crashed by an 'Illegal Instruction'.
>   It usually happens when you run it on a CPU different than the one it
> was
>   compiled/optimized for.
>   Verify this!

So MPlayer already provides a reasonable error message which explains how 
to solve the problem.

Most likely you can fix this issue by adding extra '--disable-armv6' configure
option. But it is interesting to know why cpu features autodetection fails.
Can you provide a part of 'configure.log' which contains information related
to ARMv6 check (and optionally also ARMv5TE and IWMMXT checks if they 
contain anything interesting too)?

Normally you should have something like this in it (unless -mcpu or -march is
set to cpu which can support ARMv6 instructions):

##########################################

============ Checking for ARMv6 (SIMD instructions) ============

int main(void) { __asm__ __volatile__ ("sadd16 r0, r0, r0"); }

cc -Wall -Wno-switch -O4 -pipe -ffast-math -fomit-frame-pointer      -o /var/tmp/mplayer-conf-17897-31363.o /var/tmp/mplayer-conf-10297-31363.c
/var/tmp/mplayer-conf-10297-31363.c: In function `main':
/var/tmp/mplayer-conf-10297-31363.c:1: warning: control reaches end of 
non-void function
{standard input}: Assembler messages:
{standard input}:14: Error: selected processor does not support `sadd16 
r0,r0,r0'


Result is: no
##########################################