Bug#901701: bumblebee: using optirun introduces segfault in i965_dri.so

[Vincas Dargis <vindrg@gmail.com>]

Sadly, `PRIMUS_UPLOAD=1 primusrun glxgears` does not work any more, also segfaults:

Thread 2 "glxgears" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7f3a8041c700 (LWP 12698)]
0x00007f3a8152b2ef in do_blit_drawpixels (pixels=0x0, unpack=0x7f3a78150598, type=5121, 
format=32993, height=1080, width=1920, y=0, x=0, ctx=0x7f3a78147010)
    at ../../../../../../src/mesa/drivers/dri/i965/intel_pixel_draw.c:83
83      ../../../../../../src/mesa/drivers/dri/i965/intel_pixel_draw.c: Toks failas ar aplankas 
neegzistuoja.
(gdb) bt
#0  0x00007f3a8152b2ef in do_blit_drawpixels (pixels=0x0, unpack=0x7f3a78150598, type=5121, 
format=32993, height=1080, width=1920, y=0, x=0,
    ctx=0x7f3a78147010) at ../../../../../../src/mesa/drivers/dri/i965/intel_pixel_draw.c:83 

#1  intelDrawPixels (ctx=0x7f3a78147010, x=0, y=0, width=1920, height=1080, format=32993, type=5121, 
unpack=0x7f3a78150598, pixels=0x0)
    at ../../../../../../src/mesa/drivers/dri/i965/intel_pixel_draw.c:167
#2  0x00007f3a8118039c in _mesa_DrawPixels (width=1920, height=1080, format=32993, type=5121, 
pixels=0x0) at ../../../src/mesa/main/drawpix.c:162
#3  0x00007f3a86fb7345 in test_drawpixels_fast (dconfig=<optimized out>, ctx=0x7f3a78023ae0, 
dpy=0x7f3a78000b20) at libglfork.cpp:362
#4  display_work (vd=<optimized out>) at libglfork.cpp:402
#5  0x00007f3a86537f2a in start_thread (arg=0x7f3a8041c700) at pthread_create.c:463 

#6  0x00007f3a867e5edf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Applications can be launched only on integrated Intel graphics.