pkg/51954: alsa crashes firefox for me

[martin%NetBSD.org@localhost]

>Number:         51954
>Category:       pkg
>Synopsis:       alsa crashes firefox for me
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Feb 06 11:25:00 +0000 2017
>Originator:     Martin Husemann
>Release:        NetBSD 7.99.59
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD whoever-brings-the-night.aprisoft.de 7.99.59 NetBSD 7.99.59 (WHOEVER) #97: Fri Jan 27 09:13:10 CET 2017 martin%martins.aprisoft.de@localhost:/ssd/src/sys/arch/sparc64/compile/WHOEVER sparc64
Architecture: sparc64
Machine: sparc64
>Description:

I installed firefox-51.0.1 but did not configure alsa or anything
(I usually do not use audio with Firefox).

When visiting sites that try to play audio, it crashes.

Thread 6 received signal SIGTRAP, Trace/breakpoint trap.
[Switching to LWP 170]
poll (fds=0xffffffffd0305d18, nfds=<optimized out>, timeout=timeout@entry=1000)
    at /ssd/src/lib/libpthread/pthread_cancelstub.c:413
413     /ssd/src/lib/libpthread/pthread_cancelstub.c: No such file or directory.
(gdb) bt
#0  poll (fds=0xffffffffd0305d18, nfds=<optimized out>, timeout=timeout@entry=1000)
    at /ssd/src/lib/libpthread/pthread_cancelstub.c:413
#1  0xffffffffdfe13474 in alsa_run (ctx=0xffffffffbb78f000)
    at /usr/pkgobj/www/firefox/work/firefox-51.0.1/media/libcubeb/src/cubeb_alsa.c:421
#2  alsa_run_thread (context=0xffffffffbb78f000)
    at /usr/pkgobj/www/firefox/work/firefox-51.0.1/media/libcubeb/src/cubeb_alsa.c:475
#3  0xffffffffe280d8f8 in pthread__create_tramp (cookie=0xffffffffc938a000) at /ssd/src/lib/libpthread/pthread.c:576
(gdb) up
#1  0xffffffffdfe13474 in alsa_run (ctx=0xffffffffbb78f000)
    at /usr/pkgobj/www/firefox/work/firefox-51.0.1/media/libcubeb/src/cubeb_alsa.c:421
421       r = poll(ctx->fds, ctx->nfds, timeout);
(gdb) p timeout
$1 = 1000
(gdb) p *ctx
$2 = {ops = 0xffffffffe1490ee0 <alsa_ops>, thread = 0xffffffffc938a000, mutex = {ptm_magic = 858980355, 
    ptm_errorcheck = 0 '\000', ptm_pad1 = "\000\000", {ptm_ceiling = 0 '\000', ptm_unused = 0 '\000'}, ptm_pad2 = "\000\000", 
    ptm_owner = 0x0, ptm_waiters = 0x0, ptm_recursed = 0, ptm_spare2 = 0x0}, streams = {0x0 <repeats 16 times>}, 
  fds = 0xffffffffd0305d18, nfds = 1, rebuild = 0, shutdown = 0, control_fd_read = 98, control_fd_write = 101, 
  active_streams = 0, local_config = 0x0, is_pa = 0, libasound = 0xffffffffe20dd000}
(gdb) p *ctx->fds
$3 = {fd = 98, events = 9, revents = 0}


>How-To-Repeat:

Surf to https://upload.wikimedia.org/wikipedia/commons/b/b2/En-us-king.ogg
This makes it crash on my amd64 notebook too.

>Fix:
n/a