sarnex@pc ~ $ LIBGL_DEBUG=verbose gdb glxgears
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Reading symbols from glxgears...(no debugging symbols found)...done.
(gdb)  b radeon_bomgr_create_bo if size == 0
Function "radeon_bomgr_create_bo" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y

Breakpoint 1 (radeon_bomgr_create_bo if size == 0) pending.
(gdb) run
Starting program: /usr/bin/glxgears
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
libGL: screen 0 does not appear to be DRI3 capable
libGL: pci id for fd 4: 1002:679a, driver radeonsi
libGL: OpenDriver: trying /usr/lib/x86_64-linux-gnu/dri/tls/radeonsi_dri.so
libGL: OpenDriver: trying /usr/lib/x86_64-linux-gnu/dri/radeonsi_dri.so
[New Thread 0x7fffefd0f700 (LWP 4804)]
libGL: Can't open configuration file /home/sarnex/.drirc: No such file or directory.
libGL: Can't open configuration file /home/sarnex/.drirc: No such file or directory.
Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.

Breakpoint 1, radeon_bomgr_create_bo (_mgr=0x640fe0, size=0,
    desc=0x7fffffffdcc0)
    at ../../../../../../../src/gallium/winsys/radeon/drm/radeon_drm_bo.c:487
487	../../../../../../../src/gallium/winsys/radeon/drm/radeon_drm_bo.c: No such file or directory.
(gdb) bt full
#0  radeon_bomgr_create_bo (_mgr=0x640fe0, size=0, desc=0x7fffffffdcc0)
    at ../../../../../../../src/gallium/winsys/radeon/drm/radeon_drm_bo.c:487
        rws = <optimized out>
        bo = <optimized out>
        args = {size = 7752720, alignment = 140737342637920, handle = 536800,
          initial_domain = 0, flags = 72}
        rdesc = <optimized out>
        r = <optimized out>
#1  0x00007ffff3470a02 in pb_cache_manager_create_buffer (_mgr=0x641120,
    size=0, desc=0x7fffffffdcc0)
    at ../../../../../src/gallium/auxiliary/pipebuffer/pb_bufmgr_cache.c:331
        buf = 0x792250
        curr_buf = <optimized out>
        curr = <optimized out>
        next = <optimized out>
        ret = <optimized out>
#2  0x00007ffff36b6631 in radeon_winsys_bo_create (rws=<optimized out>,
    size=<optimized out>, alignment=<optimized out>,
    use_reusable_pool=<optimized out>, domain=<optimized out>,
    flags=<optimized out>)
    at ../../../../../../../src/gallium/winsys/radeon/drm/radeon_drm_bo.c:829
        desc = {base = {alignment = 4096, usage = 4}, initial_domains = 4,
          flags = 1}
---Type <return> to continue, or q <return> to quit---
        provider = <optimized out>
        buffer = <optimized out>
#3  0x00007ffff36c15b0 in r600_init_resource (rscreen=rscreen@entry=0x642330,
    res=res@entry=0x7921c0, size=<optimized out>,
    alignment=alignment@entry=4096,
    use_reusable_pool=use_reusable_pool@entry=true)
    at ../../../../../../src/gallium/drivers/radeon/r600_buffer_common.c:157
        rtex = 0x7921c0
        old_buf = <optimized out>
        new_buf = <optimized out>
        flags = <optimized out>
#4  0x00007ffff36c17b7 in r600_buffer_create (screen=0x642330,
    templ=0x7fffffffdda0, alignment=4096)
    at ../../../../../../src/gallium/drivers/radeon/r600_buffer_common.c:394
        rscreen = 0x642330
        rbuffer = 0x7921c0
#5  0x00007ffff36c7f46 in pipe_buffer_create (bind=131072, usage=0,
    size=<optimized out>, screen=0x642330)
    at ../../../../../../src/gallium/auxiliary/util/u_inlines.h:253
        buffer = {reference = {count = 0}, screen = 0x0, target = PIPE_BUFFER,
          format = PIPE_FORMAT_R8_UNORM, width0 = 0, height0 = 1, depth0 = 1,
          array_size = 1, last_level = 0, nr_samples = 0, usage = 0,
          bind = 131072, flags = 0}
---Type <return> to continue, or q <return> to quit---
#6  r600_texture_alloc_cmask_separate (rtex=0x720880, rscreen=<optimized out>)
    at ../../../../../../src/gallium/drivers/radeon/r600_texture.c:468
No locals.
#7  evergreen_do_fast_color_clear (rctx=rctx@entry=0x6a0e10,
    fb=fb@entry=0x6a14d8, fb_state=fb_state@entry=0x6a14c8,
    buffers=buffers@entry=0x7fffffffde3c, color=color@entry=0x76f99c)
    at ../../../../../../src/gallium/drivers/radeon/r600_texture.c:1294
        tex = 0x720880
        clear_bit = 4
        i = 0
#8  0x00007ffff376db2f in si_clear (ctx=0x6a0e10, buffers=5, color=0x76f99c,
    depth=1, stencil=0)
    at ../../../../../../src/gallium/drivers/radeonsi/si_blit.c:326
        sctx = 0x6a0e10
        fb = 0x6a14d8
#9  0x00007ffff33644f5 in st_Clear (ctx=0x76e1c0, mask=18)
    at ../../../../src/mesa/state_tracker/st_cb_clear.c:518
        depthRb = <optimized out>
        stencilRb = <optimized out>
        quad_buffers = <optimized out>
        clear_buffers = 5
        i = <optimized out>
#10 0x00000000004025ae in ?? ()
---Type <return> to continue, or q <return> to quit---
No symbol table info available.
#11 0x0000000000401dc4 in ?? ()
No symbol table info available.
#12 0x00007ffff716aec5 in __libc_start_main (main=0x401940, argc=1,
    argv=0x7fffffffe1a8, init=<optimized out>, fini=<optimized out>,
    rtld_fini=<optimized out>, stack_end=0x7fffffffe198) at libc-start.c:287
        result = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {0, 4979810275811823671,
                4203397, 140737488347552, 0, 0, -4979810276519276489,
                -4979792467250343881}, mask_was_saved = 0}}, priv = {pad = {
              0x0, 0x0, 0x403970, 0x7fffffffe1a8}, data = {prev = 0x0,
              cleanup = 0x0, canceltype = 4209008}}}
        not_first_call = <optimized out>
#13 0x00000000004023ae in ?? ()
No symbol table info available.