As you can see, the same line of nv_xaa.c, but a different path.
Reading symbols from /usr/X11R6/bin/Xorg-debug...bt
done.
Reading symbols from /usr/lib/libfreetype.so.6...done.
Loaded symbols for /usr/lib/libfreetype.so.6
Reading symbols from /usr/lib/libz.so.1...done.
Loaded symbols for /usr/lib/libz.so.1
Reading symbols from /lib/tls/libm.so.6...done.
Loaded symbols for /lib/tls/libm.so.6
Reading symbols from /usr/X11R6/lib/libXau.so.6...done.
Loaded symbols for /usr/X11R6/lib/libXau.so.6
Reading symbols from /usr/X11R6/lib/libXdmcp.so.6...done.
Loaded symbols for /usr/X11R6/lib/libXdmcp.so.6
Reading symbols from /lib/tls/libc.so.6...done.
Loaded symbols for /lib/tls/libc.so.6
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
0x080ecc33 in NVSync (pScrn=0x8ba2368) at nv_xaa.c:301
301 nv_xaa.c: No such file or directory.
in nv_xaa.c
(gdb) bt
#0 0x080ecc33 in NVSync (pScrn=0x8ba2368) at nv_xaa.c:301
#1 0x083c812f in XAAGlyphs (op=3 '\003', pSrc=0x957b088,
pDst=0x93076d8, maskFormat=0x8ba4560, xSrc=0, ySrc=0, nlist=1,
list=0xbfdedc1c, glyphs=0xbfded81c) at xaaPict.c:757
#2 0x08694fc0 in cwGlyphs (op=3 '\003', pSrcPicture=0x957b088,
pDstPicture=0x93076d8, maskFormat=0x8ba4560, xSrc=0,
ySrc=0, nlists=1, lists=0xbfdedc1c, glyphs=0xbfded81c) at cw_render.c:299
#3 0x08687f9e in damageGlyphs (op=3 '\003', pSrc=0x957b088,
pDst=0x93076d8, maskFormat=0x8ba4560, xSrc=0, ySrc=0, nlist=1,
list=0xbfdedc1c, glyphs=0xbfded81c) at damage.c:594
#4 0x0897fb9e in CompositeGlyphs (op=3 '\003', pSrc=0x957b088,
pDst=0x93076d8, maskFormat=0x8ba4560, xSrc=0, ySrc=0,
nlist=1, lists=0xbfdedc1c, glyphs=0xbfded81c) at picture.c:1387
#5 0x08982ea6 in ProcRenderCompositeGlyphs (client=0x8e3e560) at render.c:1361
#6 0x08984350 in ProcRenderDispatch (client=0x8e3e560) at render.c:1846
#7 0x0851233e in Dispatch () at dispatch.c:455
#8 0x08529a91 in main (argc=7, argv=0xbfdee4b4, envp=0xbfdee4d4) at main.c:476
