/usr/include/alsa/pcm.h contains:
#define snd_pcm_sw_params_alloca(ptr) do { assert(ptr); *ptr = (snd_pcm_sw_params_t *) alloca(snd_pcm_sw_params_sizeof()); memset(*ptr, 0, snd_pcm_sw_params_sizeof()); } while (0)
The assert generates: "error: the address of 'sw_params' will always
evaluate as 'true'" which combined with -Werror prevents alsaaudio.o
from being built with certain versions of GCC.
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