just checked out CVS using the xserver build script from the wiki.

(gdb) r :1
Starting program: /opt/fdo/bin/Xephyr :1

Program received signal SIGSEGV, Segmentation fault.
0x08096a59 in fbValidateGC (pGC=0x8134370, changes=8388607,
    pDrawable=0x8129888) at fbgc.c:217
217             pPriv->oneRect = REGION_NUM_RECTS(fbGetCompositeClip(pGC)) ==
1;(gdb) list
212         if ((changes &
(GCClipXOrigin|GCClipYOrigin|GCClipMask|GCSubwindowMode)) ||
213             (pDrawable->serialNumber != (pGC->serialNumber &
DRAWABLE_SERIAL_BITS))
214             )
215         {
216             miComputeCompositeClip (pGC, pDrawable);
217             pPriv->oneRect = REGION_NUM_RECTS(fbGetCompositeClip(pGC)) ==
1;218         }
219
220     #ifdef FB_24_32BIT
221         if (pPriv->bpp != pDrawable->bitsPerPixel)
(gdb) bt
#0  0x08096a59 in fbValidateGC (pGC=0x8134370, changes=8388607,
    pDrawable=0x8129888) at fbgc.c:217
#1  0x08102c22 in damageValidateGC (pGC=0x8134370, changes=8388607,
    pDrawable=0x8129888) at damage.c:379
#2  0x080710d7 in ValidateGC (pDraw=0x8129888, pGC=0x8134370) at gc.c:80
#3  0x08072f0a in ServerBitsFromGlyph (pfont=0x1, ch=1919905325,
    cm=0xbf95c78c, ppbits=0x1) at glyphcurs.c:128
#4  0x0806744c in AllocGlyphCursor (source=61, sourceChar=0, mask=61,
    maskChar=1, foreRed=1, foreGreen=1, foreBlue=1, backRed=1, backGreen=1,
    backBlue=1, ppCurs=0x1, client=0x8129528) at cursor.c:331
#5  0x0806750d in CreateRootCursor (pfilename=0x8129528 "", glyph=0)
    at cursor.c:456
#6  0x0805850f in main (argc=2, argv=0xbf95c974, envp=0xbf95c980) at main.c:396
(gdb) print pPriv
$1 = 0x726f6e2d
(gdb) print *pPriv
Cannot access memory at address 0x726f6e2d
(gdb)