On Thu, 2007-05-10 at 13:29 +0200, Michel Benoit wrote:
I put this problem aside for a while but I have now managed to narrow it down a little
I'm trying to build alsa-lib 1.0.13 for a at91sam9260 target (arm926ej-s). I'm using gcc 4.1.2 built with buildroot (uclibc). I seem to be having a problem passing in arguments to some libasound functions.
Iirc, the compiler bug also showed up on the dummy alsa device. Does the same thing happen when playing to the ALSA dummy device on AT91 ?
I have added some printfs to the following lib function (src/pcm.c):
int snd_pcm_hw_params_get_period_size(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir) { unsigned long _val;
printf("get_period_size() %lu %lu %08x %08x %08x \n", _val,*val, val, dir, params );
int err = snd_pcm_hw_param_get(params, SND_PCM_HW_PARAM_PERIOD_SIZE,&_val, NULL); if (err >= 0) *val = _val;
printf("get_period_size() %lu %lu %08x %08x %08x %d\n", _val,*val, val, dir, params, err );
return err;}
as well as to the program that calls the lib function (test/pcm.c):
printf("period_size=%lu %08x dir=%d %08x params %08x \n",size, &size, dir, &dir, params); err = snd_pcm_hw_params_get_period_size(params, &size, NULL); if (err < 0) { printf("Unable to get period size for playback: %s\n", snd_strerror(err)); return err; } period_size = size; printf("period_size=%lu %08x dir=%d %08x params %08x \n", size, &size, dir, &dir, params);
When I run the program I get the following output
# pcm Playback device is plughw:0,0
It's best to change this to hw:0,0 to help rule out any AT91 driver issues.
Stream parameters are 44100Hz, S16_LE, 1 channels Sine wave rate is 440.0000Hz Using transfer method: write period_size=49572 bec48954 dir=0 bec48950 params bec489e4 get_period_size() 1073758756 3200551252 bec48924 bec48954 bec489e4 get_period_size() 1248 1248 bec48924 bec48954 bec489e4 0 period_size=49572 bec48954 dir=0 bec48950 params bec489e4
which shows that the pointers to 'params' is ok but that the pointer to 'val' is incorrect (bec48924 instead of bec48954) and the pointer to 'dir' is also wrong (bec48954 instead of bec48950 = the pointer to val).
What could be the cause of this kind of error? Somehow the arguments passed to snd_pcm_hw_params_get_period_size() are getting mangled.
I have tried removing all optimisations, using other versions of gcc (4.0.4 and 3.4.6) and using EABI instead of OABI. I always get the same result.
Any tips on how I can proceed in debugging this problem?
Are there any compiler or linker flags that could be responsible ?
Did you build any of the toolchains with OE ? I've not had any audio gcc problems on ARM with OE toolchains since the cse bug.
Liam