On Monday 20 April 2015 12:17, Alan Horstmann wrote:
On Saturday 18 April 2015 09:08, Alan Horstmann wrote:
The following assert is being hit in pcm_params.c:
"pcm_params.c:2249: snd1_pcm_hw_params_slave: Assertion `err >= 0' failed."
This is from a developer using Portaudio in his own application; I have yet to ascertain full details, but it is trying successive sample rates to see which are valid.
Further info: this occurs with an Intel motherboard/soundcard, attempting to open and config the stream at 44100 using front, surround or hdmi pcm, having previously opened and tried at a lower, not-supported samplerate, and closed. AFAIK other pcms work OK.
The assert is hit with all current Debian and Ubuntu distros, for example Debian 8 (jessie) 32 bit: kernel 3.16.0-4-686-pae (Alsa 1.0.28) but is not seen with Fedora 20 or OpenSuse 12.1 (do they have asserts off?).
Does this point to a flaw in the configuration or possibly a bug in Alsa-lib or can it occur just as a result of misuse of the Alsa API?
I will try to conceive some more tests. How can we debug this further?
A minimal self-contained demo program ('test-format') has been developed and is attached, that demonstrates the issue 100% on the reporters machine (HDA-Intel, 6-ch I believe). The output is:
root@Xeon:/home/patest# ./test-format Testing device front Num channels 6 Testing rate: 22050 Result:...Invalid Sample Rate Testing rate: 32000 Result:...Invalid Sample Rate test-format: pcm_params.c:2249: snd1_pcm_hw_params_slave: Assertion `err >= 0' failed. Testing rate: 44100 Aborted
Alsa-info is at:
http://www.alsa-project.org/db/?f=19dfeee29f73007e61a00a8fabe3c958f7cb8e87
This apparently happens with or without Pulseaudio running, with just the single 44100 rate, and also with surround devices. Also, on all current Debian and Ubuntu - we have focused on Jessie.
I do not have a machine with similar hardware, so cannot duplicate the results.
Any comments, ideas etc would be appreciated.
Regards
Alan