Comment 16 for bug 1378627

It doesn't crash with LIBGL_DRI3_DISABLE=1.

mesa-dri-drivers-10.2.5-1.20140806.fc21.x86_64
xorg-x11-drv-intel-2.99.914-1.fc21.x86_64
libdrm-2.4.56-1.fc21.x86_64
xorg-x11-server-Xorg-1.16.0-1.fc21.x86_64
kernel-3.16.1-300.fc21.x86_64
google-chrome-unstable-38.0.2125.0-1.x86_64

I've tried Mesa master (76f687d5a5be9d3bce8d05bcfef97a3d74ca1f18) and xf86-video-intel master (f5469681b620d9d6ccaf53e92ed31f931cb03b0d), but it's the same.

Core was generated by `/opt/google/chrome-unstable/chrome --type=gpu-process --channel=2180.0.73132887'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 get_stencil_miptree (irb=<optimized out>) at brw_misc_state.c:225
225 if (irb->mt->stencil_mt)
(gdb) bt
#0 0x00007f80fb33a51f in brw_workaround_depthstencil_alignment (irb=<optimized out>) at brw_misc_state.c:225
#1 0x00007f80fb33a51f in brw_workaround_depthstencil_alignment (brw=0x3f6385fa2028, clear_mask=clear_mask@entry=50) at brw_misc_state.c:241
#2 0x00007f80fb2f09d0 in brw_clear (ctx=0x3f6385fa2028, mask=50) at brw_clear.c:235
#3 0x00007f8114982816 in ()
#4 0x0000000000000000 in ()
(gdb) up
#1 brw_workaround_depthstencil_alignment (brw=0x1fca0ea81028, clear_mask=clear_mask@entry=50) at brw_misc_state.c:241
241 struct intel_mipmap_tree *stencil_mt = get_stencil_miptree(stencil_irb);
(gdb) p *(struct intel_renderbuffer *)(brw->ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer)
$11 = {Base = {Base = {Mutex = {__data = {__lock = 0, __count = 0, __owner = 0, __nusers = 0, __kind = 0, __spins = 0, __elision = 0, __list = {__prev = 0x0, __next = 0x0}},
        __size = '\000' <repeats 39 times>, __align = 0}, ClassID = 305419896, Name = 0, Label = 0x0, RefCount = 1, Width = 0, Height = 0, Depth = 0, Purgeable = 0 '\000',
      AttachedAnytime = 0 '\000', NeedsFinishRenderTexture = 0 '\000', NumSamples = 0 '\000', InternalFormat = 6402, _BaseFormat = 6402, Format = MESA_FORMAT_Z24_UNORM_X8_UINT, TexImage = 0x0,
      Delete = 0x7f41ed700240 <intel_delete_renderbuffer>, AllocStorage = 0x7f41ed701480 <intel_alloc_private_renderbuffer_storage>}, Buffer = 0x0, Map = 0x0, RowStride = 0, ColorType = 0},
  mt = 0x0, singlesample_mt = 0x0, mt_level = 0, mt_layer = 0, layer_count = 1, draw_x = 0, draw_y = 0, need_downsample = false, need_map_upsample = false, singlesample_mt_is_tmp = false}

The crash happens since mt is 0, but other members looks strange (Width, Height, ...).