ALSA return code being incorrectly checked

[danw-volley]

mpv version and platform

Git master HEAD 2b6ac86

Reproduction steps

Code Review

Expected behavior

Check the correct ALSA return value

Actual behavior

Check the wrong ALSA return value

Log file

In audio/out/ao_alsa.c starting on line 1123 there is this code:

        unsigned short revents;
        snd_pcm_poll_descriptors_revents(p->alsa, fds, num_fds, &revents);
        CHECK_ALSA_ERROR("cannot read poll events");

The results of snd_pcm_poll_descriptors_revents is not being stored in the err variable, so the macro is not checking the correct return value. I believe it should be:

        unsigned short revents;
        err = snd_pcm_poll_descriptors_revents(p->alsa, fds, num_fds, &revents);
        CHECK_ALSA_ERROR("cannot read poll events");

[ghost]

That's probably right.