$ gdb pulseaudio 
GNU gdb (Gentoo 7.10.1 vanilla) 7.10.1
Copyright (C) 2015 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-pc-linux-gnux32".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.gentoo.org/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from pulseaudio...Reading symbols from /usr/lib/debug//usr/bin/pulseaudio.debug...done.
done.
(gdb) run
Starting program: /usr/bin/pulseaudio 
warning: linux_ptrace_test_ret_to_nx: Cannot PTRACE_PEEKUSER: Input/output error
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/libx32/libthread_db.so.1".
(gdb) process 2081 is executing new program: /usr/bin/pulseaudio
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/libx32/libthread_db.so.1".
W: [pulseaudio] pid.c: Stale PID file, overwriting.
[New Thread 0xee107940 (LWP 2085)]
[New Thread 0xed7a8940 (LWP 2086)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xee107940 (LWP 2085)]
0xf7fd90c0 in ?? ()
(gdb) bt
#0  0xf7fd90c0 in ?? ()
#1  0xf7ba89ea in pa_volume_s16ne_orc_2ch (d1=<optimized out>, p1=<optimized out>, n=1701)
    at pulsecore/svolume-orc-gen.c:555
#2  0xf7b71e05 in pa_volume_memchunk (c=c@entry=0xee104c30, spec=spec@entry=0x6bbba0, volume=volume@entry=0xee104c40)
    at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/mix.c:723
#3  0xf7b83f4d in pa_sink_render_into (s=s@entry=0x6bbb60, target=target@entry=0xee107020)
    at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/sink.c:1311
#4  0xf7b840e8 in pa_sink_render_into_full (s=<optimized out>, target=target@entry=0xee1070f0)
    at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/sink.c:1367
#5  0xee41e76b in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x631420)
    at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/modules/alsa/alsa-sink.c:645
#6  thread_func (userdata=<optimized out>)
    at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/modules/alsa/alsa-sink.c:1717
#7  0xf76cac56 in internal_thread_func (userdata=<optimized out>)
    at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/thread-posix.c:81
#8  0xf7059de5 in start_thread (arg=<optimized out>) at pthread_create.c:334
#9  0xf6ba18fd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109


(gdb) bt full
#0  0xf7fd90c0 in ?? ()
No symbol table info available.
#1  0xf7ba89ea in pa_volume_s16ne_orc_2ch (d1=<optimized out>, p1=<optimized out>, n=1701) at pulsecore/svolume-orc-gen.c:555
        _ex = {program = 0x0, n = 1701, counter1 = 0, counter2 = 425, counter3 = 1, arrays = {0xefa20028, 0xf7063056 <__libc_send+150>, 0x0, 0x0, 0x77, 0xee1048d0, 0x0, 0xf7ffb82a, 0x0, 0xf7062b49 <write+57>, 0x0, 0x0, 0x0, 0xed80f650, 
            0x0, 0x632f90, 0x0, 0xee104900, 0x0, 0x632f9c, 0x0, 0xee1048ff, 0x0, 0x0, 0x0, 0xf76ad431 <pa_memblock_acquire_chunk+17>, 0x0, 0x66d110, 0x0, 0xf7b6e26b <peaks_resample+587>, 0x0, 0x1, 0x0, 
            0xf76adf80 <pa_memblock_new_pool+224>, 0xef8d0028, 0x7329c8, 0x0, 0x7329d4, 0x0, 0xee104978, 0x0, 0xef8e0028, 0x2, 0x6780e0, 0x0, 0x732880, 0x0, 0x7329c8, 0x0, 0x7329d4, 0x0, 0xc, 0x0, 0x7329b8, 0x0, 0xee104a30, 0x0, 
            0xf7b6aca2 <resample+226>, 0x0, 0x732880, 0x0, 0x0, 0xdbede900, 0xf76b0a60 <list_items_flist_init>}, params = {0, -141621428, 0, -143979936, 0, -144030770, 0, 3500, 0, 0, 0, 0, 0, -143978396, 0, 0, 0, 65496, 0, 7060224, 0, 
            6651488, 0, -300922352, 28775, 6651488, 0, -300922352, 0, 6651488, 0, -300922352, 28775, 6651488, 0, -300921648, 0, -143976453, 0, 7573120, 0, -300922192, 0, 65496, 0, -138967303, 0, 0, 0, -300922176, 0, 14901, 14901, 
            7574004, 0, 7574240, 0, -300922176, 6804, -300922208, 0, -300922160, 0, -300921648}, accumulators = {0, -141409672, 49811, 6804}}
        ex = 0xee104870
        p_inited = 1
        c = 0xed80f650
        func = <optimized out>
#2  0xf7b71e05 in pa_volume_memchunk (c=c@entry=0xee104c30, spec=spec@entry=0x6bbba0, volume=volume@entry=0xee104c40) at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/mix.c:723
        ptr = <optimized out>
        linear = {{f = 4.03223633e-41, i = 28775} <repeats 34 times>, {f = -4.75145589e+33, i = 4150936526}, {f = 0, i = 0}, {f = 0, i = 0}, {f = 0, i = 0}, {f = 8.93041906e-39, i = 6372960}, {f = 0, i = 0}, {f = 8.93041906e-39, 
            i = 6372960}, {f = 0, i = 0}, {f = -4.76196476e+33, i = 4150970482}, {f = 0, i = 0}, {f = -1.11644866e+28, i = 3994045488}, {f = 0, i = 0}, {f = -4.76379134e+33, i = 4150976384}, {f = 0, i = 0}, {f = 9.89361557e-39, 
            i = 7060320}, {f = 0, i = 0}, {f = -1.11644866e+28, i = 3994045488}, {f = 0, i = 0}, {f = 8.93041906e-39, i = 6372960}, {f = 0, i = 0}, {f = 9.53443475e-42, i = 6804}, {f = 0, i = 0}, {f = -1.11646755e+28, i = 3994045648}, {
            f = 0, i = 0}, {f = -4.76389935e+33, i = 4150976733}, {f = 0, i = 0}, {f = 0, i = 0}, {f = 0, i = 0}, {f = -1.11644866e+28, i = 3994045488}, {f = 0, i = 0}}
        do_volume = <optimized out>
        __func__ = "pa_volume_memchunk"
        __PRETTY_FUNCTION__ = "pa_volume_memchunk"
#3  0xf7b83f4d in pa_sink_render_into (s=s@entry=0x6bbb60, target=target@entry=0xee107020) at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/sink.c:1311
        vchunk = {memblock = 0xefa20000, index = 0, length = 6804}
        volume = {channels = 2 '\002', values = {49811, 49811, 0 <repeats 30 times>}}
        info = {{chunk = {memblock = 0xefa10000, index = 0, length = 6804}, volume = {channels = 2 '\002', values = {65536, 65536, 0 <repeats 30 times>}}, userdata = 0x738e80, ptr = 0x0, linear = {{i = 0, f = 0} <repeats 32 times>}}, {
            chunk = {memblock = 0x0, index = 0, length = 0}, volume = {channels = 0 '\000', values = {0 <repeats 32 times>}}, userdata = 0x0, ptr = 0x0, linear = {{i = 0, f = 0} <repeats 32 times>}} <repeats 27 times>, {chunk = {
              memblock = 0x0, index = 0, length = 0}, volume = {channels = 0 '\000', values = {0 <repeats 24 times>, 4139898794, 0, 49, 5, 80, 5, 1, 50}}, userdata = 0x0, ptr = 0x5b, linear = {{i = 0, f = 0}, {i = 0, f = 0}, {i = 0, 
                f = 0}, {i = 119, f = 1.66754517e-43}, {i = 0, f = 0}, {i = 124, f = 1.7376101e-43}, {i = 0, f = 0}, {i = 0, f = 0}, {i = -310378472, f = -4.95177432e+27}, {i = 0, f = 0}, {i = 49, f = 6.86636248e-44}, {i = 0, f = 0}, {
                i = -310378472, f = -4.95177432e+27}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = -141409672, f = -5.932996e+33}, {i = 0, f = 0}, {i = -155068502, f = -1.96579586e+33}, {i = 0, f = 0}, {i = 7574240, 
                f = 1.06137709e-38}, {i = 0, f = 0}, {i = 7573872, f = 1.06132552e-38}, {i = 0, f = 0}, {i = -141409480, f = -5.93311484e+33}, {i = 0, f = 0}, {i = 7060320, f = 9.89361557e-39}, {i = 0, f = 0}, {i = 7573120, 
                f = 1.06122014e-38}, {i = 0, f = 0}, {i = 7573872, f = 1.06132552e-38}, {i = 0, f = 0}}}, {chunk = {memblock = 0xf7b8e151 <pa_sink_process_msg+337>, index = 0, length = 0}, volume = {channels = 116 't', values = {
                3984588824, 0, 120, 0, 3984588824, 0, 273, 0, 4138560716, 0, 4139898591, 0, 4294967295, 3689801984, 3994053856, 0, 7060320, 0, 0, 0, 0, 0, 0, 0, 6493216, 0, 4, 0, 3997291604, 0, 0, 0}}, userdata = 0x0, ptr = 0x0, 
            linear = {{i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 1229800520, f = 840772.5}, {i = 12320, f = 1.72639971e-41}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {
                i = -605165312, f = -1.33931511e+17}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 7060320, f = 9.89361557e-39}, {i = 0, f = 0}, {i = -297676064, f = -1.49963848e+28}, {i = 0, f = 0}, {i = -138735798, f = -7.58804384e+33}, {
                i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 6493216, f = 9.09893361e-39}, {i = 0, f = 0}, {i = 3, f = 4.20389539e-45}, {i = 0, f = 0}, {i = -138932879, f = -7.46605661e+33}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, 
                f = 0}, {i = -1, f = -nan(0x7fffff)}, {i = -605165312, f = -1.33931511e+17}}}, {chunk = {memblock = 0x6bbb60, index = 0, length = 0}, volume = {channels = 0 '\000', values = {3, 0, 4156091304, 0, 0, 0, 4153557624, 0, 0, 
                0, 7306980, 0, 7306628, 0, 4153557816, 0, 6551520, 0, 7305888, 3689801984, 7306980, 0, 7060320, 0, 0, 0, 0, 0, 0, 0, 6493216, 0}}, userdata = 0x3, ptr = 0x0, linear = {{i = -297675692, f = -1.4996824e+28}, {i = 0, f = 0}, 
              {i = -155068502, f = -1.96579586e+33}, {i = 0, f = 0}, {i = -1, f = -nan(0x7fffff)}, {i = -605165312, f = -1.33931511e+17}, {i = -138779956, f = -7.56071136e+33}, {i = 0, f = 0}, {i = -138944249, f = -7.45901892e+33}, {
                i = 0, f = 0}, {i = -144030272, f = -4.75161001e+33}, {i = 0, f = 0}, {i = -141467668, f = -5.89709821e+33}, {i = 0, f = 0}, {i = 7060384, f = 9.89370526e-39}, {i = 0, f = 0}, {i = -141467378, f = -5.89727771e+33}, {
                i = -605165312, f = -1.33931511e+17}, {i = 7056, f = 9.88756196e-42}, {i = 0, f = 0}, {i = 7060320, f = 9.89361557e-39}, {i = 0, f = 0}, {i = 7573120, f = 1.06122014e-38}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {
                i = 0, f = 0}, {i = 0, f = 0}, {i = 6493216, f = 9.09893361e-39}, {i = -605165312, f = -1.33931511e+17}, {i = 0, f = 0}, {i = 0, f = 0}}}, {chunk = {memblock = 0x0, index = 0, length = 6551520}, volume = {
              channels = 0 '\000', values = {5620, 0, 3994054696, 0, 6361152, 0, 3994054896, 0, 4150962796, 0, 40, 48, 3994054608, 3994054416, 7060320, 0, 5620, 3689801984, 3997372992, 0, 6493216, 0, 3994054896, 0, 4150962796, 0, 40, 48, 
                3994054448, 0, 3994054604, 0}}, userdata = 0xf7b51ac4 <pa_asyncq_pop+68>, ptr = 0xdbede900, linear = {{i = 7068576, f = 9.90518469e-39}, {i = 0, f = 0}, {i = 5620, f = 7.87529737e-42}, {i = 0, f = 0}, {i = -297588175, 
                f = -1.51001458e+28}, {i = 0, f = 0}, {i = 347148, f = 4.86457959e-40}, {i = 0, f = 0}, {i = -297594304, f = -1.509291e+28}, {i = 0, f = 0}, {i = -141467668, f = -5.89709821e+33}, {i = 0, f = 0}, {i = 6551584, 
                f = 9.1807246e-39}, {i = 0, f = 0}, {i = -141467378, f = -5.89727771e+33}, {i = 0, f = 0}, {i = 5620, f = 7.87529737e-42}, {i = 0, f = 0}, {i = -143934448, f = -4.7812661e+33}, {i = 0, f = 0}, {i = 7305888, 
                f = 1.02377296e-38}, {i = 0, f = 0}, {i = -300560013, f = -1.15916188e+28}, {i = 0, f = 0}, {i = 7247968, f = 1.01565664e-38}, {i = 0, f = 0}, {i = 7047920, f = 9.87623947e-39}, {i = 0, f = 0}, {i = 7047920, 
                f = 9.87623947e-39}, {i = 0, f = 0}, {i = 352768, f = 4.94333257e-40}, {i = 0, f = 0}}}}
        n = 1
        length = 6804
        block_size_max = <optimized out>
        __func__ = "pa_sink_render_into"
        __PRETTY_FUNCTION__ = "pa_sink_render_into"
#4  0xf7b840e8 in pa_sink_render_into_full (s=<optimized out>, target=target@entry=0xee1070f0) at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/sink.c:1367
        chunk = {memblock = 0xed80be20, index = 0, length = 6804}
        l = 6804
        d = 0
        __func__ = "pa_sink_render_into_full"
        __PRETTY_FUNCTION__ = "pa_sink_render_into_full"
#5  0xee41e76b in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x631420) at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/modules/alsa/alsa-sink.c:645
        chunk = {memblock = 0xed80be20, index = 0, length = 6804}
        err = <optimized out>
        frames = 1701
        sframes = <optimized out>
        written = 6804
        p = <optimized out>
        areas = 0x62dd40
---Type <return> to continue, or q <return> to quit---
        offset = 71322
        n = <optimized out>
        n_bytes = 6804
        r = <optimized out>
        after_avail = false
        process_usec = 20000
        left_to_play = <optimized out>
        input_underrun = <optimized out>
        work_done = false
        max_sleep_usec = 20000
        j = 1
#6  thread_func (userdata=<optimized out>) at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/modules/alsa/alsa-sink.c:1717
        work_done = <optimized out>
        sleep_usec = 0
        on_timeout = <optimized out>
        ret = <optimized out>
        rtpoll_sleep = 0
        real_sleep = <optimized out>
        u = <optimized out>
        revents = 0
        __func__ = "thread_func"
        __PRETTY_FUNCTION__ = "thread_func"
#7  0xf76cac56 in internal_thread_func (userdata=<optimized out>) at /var/tmp/portage/media-sound/pulseaudio-9.0/work/pulseaudio-9.0/src/pulsecore/thread-posix.c:81
        t = 0x63b090
#8  0xf7059de5 in start_thread (arg=<optimized out>) at pthread_create.c:334
        __res = <optimized out>
        pd = <optimized out>
        now = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {3994057024, 2449522143, 0, 4294950767, 3994057024, 1, 3001187331, 2570839601}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, 
              canceltype = 0}}}
        not_first_call = <optimized out>
        pagesize_m1 = <optimized out>
        sp = <optimized out>
        freesize = <optimized out>
        __PRETTY_FUNCTION__ = "start_thread"
#9  0xf6ba18fd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
No locals.