(gdb) thread apply all bt

Thread 2 (Thread 0xb4fd0b40 (LWP 4469)):
#0  0xb77b8424 in __kernel_vsyscall ()
#1  0xb72c67ab in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/i386-linux-gnu/i686/cmov/libpthread.so.0
#2  0xb74412ac in pthread_cond_wait () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
#3  0xb6bc043c in ?? () from /usr/lib/i386-linux-gnu/dri/r600_dri.so
#4  0xb72c2cf1 in start_thread () from /lib/i386-linux-gnu/i686/cmov/libpthread.so.0
#5  0xb743408e in clone () from /lib/i386-linux-gnu/i686/cmov/libc.so.6

Thread 1 (Thread 0xb72a1940 (LWP 4468)):
#0  0xb77b8424 in __kernel_vsyscall ()
#1  0xb74258ab in poll () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
#2  0xb72f2620 in ?? () from /usr/lib/i386-linux-gnu/libxcb.so.1
#3  0xb72f3f70 in ?? () from /usr/lib/i386-linux-gnu/libxcb.so.1
#4  0xb72f4237 in xcb_wait_for_reply () from /usr/lib/i386-linux-gnu/libxcb.so.1
#5  0xb75a7cfa in _XReply () from /usr/lib/i386-linux-gnu/libX11.so.6
#6  0xb76b485b in XFixesFetchRegionAndBounds () from /usr/lib/i386-linux-gnu/libXfixes.so.3
#7  0xb76b4993 in XFixesFetchRegion () from /usr/lib/i386-linux-gnu/libXfixes.so.3
#8  0x0804edc1 in is_region_empty (ps=0x9292860, region=35652032, pcache_reg=0x0) at src/compton.h:1061
#9  0x0805d2d9 in session_run (ps=0x9292860) at src/compton.c:7217
#10 0x0805d4bc in main (argc=5, argv=0xbfb3dd94) at src/compton.c:7275