Bug#414275: xorg: X randomly crashes upon mouse click

["Thibaut VARENE" <varenet@debian.org>]

Just for the records, it crashed again today (seems it's happening
more often, sigh), as usual upon mouse click.

Backtrace:
0: /usr/bin/X(xf86SigHandler+0x94) [0x1008eb98]
1: [0x100374]
2: [(nil)]
3: /lib/tls/libc.so.6 [0xfcd9610]
4: /lib/tls/libc.so.6(malloc+0xc4) [0xfcdb404]
5: /usr/bin/X(Xalloc+0x34) [0x1018d438]
6: /usr/bin/X(AllocatePixmap+0x48) [0x10025a18]
7: /usr/lib/xorg/modules/libfb.so(fbCreatePixmapBpp+0xd8) [0xf7a2e0c]
8: /usr/lib/xorg/modules/libfb.so(fbCreatePixmap+0x7c) [0xf7a2f20]
9: /usr/lib/xorg/modules/libxaa.so [0xf6dc728]
10: /usr/bin/X(miCreateAlphaPicture+0xb8) [0x101223fc]
11: /usr/bin/X(miTrapezoids+0x1b0) [0x101226e4]
12: /usr/bin/X [0x1014114c]
13: /usr/bin/X(CompositeTrapezoids+0xbc) [0x10123b80]
14: /usr/bin/X [0x1012e85c]
15: /usr/bin/X [0x1012746c]
16: /usr/bin/X(Dispatch+0x22c) [0x10043830]
17: /usr/bin/X(main+0x45c) [0x100254a0]
18: /lib/tls/libc.so.6 [0xfc7e994]
19: /lib/tls/libc.so.6(__libc_start_main+0xb0) [0xfc7ead0]

Fatal server error:
Caught signal 11.  Server aborting


The backtrace pointed me at the Composite Extension which I had
enabled (I did some compiz tests a while ago). I disabled it from now
on. I'll try testing a newer xorg-core.

Also, this time the X process got stuck: it didn't reload on its own,
and I couldn't attach gdb or kill it, I had to kill -9 it.

HTH