/usr/bin/X segfaults when enabling Multi-pointer X

[Jarkko Lietolahti]

Enable multi pointer according to https://wiki.ubuntu.com/X/MPX

When moving first mouse everything works, but when moving the second mouse X dies.

(EE) Backtrace:
(EE) 0: /usr/bin/X (xorg_backtrace+0x48) [0x7f34b1e47798]
(EE) 1: /usr/bin/X (0x7f34b1c9e000+0x1ad489) [0x7f34b1e4b489]
(EE) 2: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7f34b0d9b000+0x10340) [0x7f34b0dab340]
(EE) 3: /usr/bin/X (0x7f34b1c9e000+0x1419c8) [0x7f34b1ddf9c8]
(EE) 4: /usr/bin/X (0x7f34b1c9e000+0x14217f) [0x7f34b1de017f]
(EE) 5: /usr/bin/X (miPointerSetPosition+0x375) [0x7f34b1e33ce5]
(EE) 6: /usr/bin/X (0x7f34b1c9e000+0x6abde) [0x7f34b1d08bde]
(EE) 7: /usr/bin/X (0x7f34b1c9e000+0x6b07f) [0x7f34b1d0907f]
(EE) 8: /usr/bin/X (GetPointerEvents+0x125) [0x7f34b1d0a755]
(EE) 9: /usr/bin/X (QueuePointerEvents+0x20) [0x7f34b1d0ac40]
(EE) 10: /usr/lib/xorg/modules/input/evdev_drv.so (0x7f34a9132000+0x57fd) [0x7f34a91377fd]
(EE) 11: /usr/bin/X (0x7f34b1c9e000+0x93218) [0x7f34b1d31218]
(EE) 12: /usr/bin/X (0x7f34b1c9e000+0xbb990) [0x7f34b1d59990]
(EE) 13: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7f34b0d9b000+0x10340) [0x7f34b0dab340]
(EE) 14: /lib/x86_64-linux-gnu/libc.so.6 (__select+0x33) [0x7f34af8ab823]
(EE) 15: /usr/bin/X (WaitForSomething+0x1ac) [0x7f34b1e44cdc]
(EE) 16: /usr/bin/X (0x7f34b1c9e000+0x55961) [0x7f34b1cf3961]
(EE) 17: /usr/bin/X (0x7f34b1c9e000+0x59a9a) [0x7f34b1cf7a9a]
(EE) 18: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xf5) [0x7f34af7daec5]
(EE) 19: /usr/bin/X (0x7f34b1c9e000+0x44efe) [0x7f34b1ce2efe]
(EE)
(EE) Segmentation fault at address 0x10
(EE)
Fatal server error:
(EE) Caught signal 11 (Segmentation fault). Server aborting
(EE)
(EE)
Please consult the The X.Org Foundation support
         at http://wiki.x.org