Turns out that's legal, and xts exercises it, and we crash:
Thread 1 "Xwayland" received signal SIGSEGV, Segmentation fault.
dixGetPrivate (key=0x813660 <xwl_window_private_key>, privates=0x20) at ../../include/privates.h:122
122 return (char *) (*privates) + key->offset;
(gdb) bt
#0 dixGetPrivate (key=0x813660 <xwl_window_private_key>, privates=0x20) at ../../include/privates.h:122
#1 dixLookupPrivate (key=0x813660 <xwl_window_private_key>, privates=0x20) at ../../include/privates.h:166
#2 xwl_window_of_top (window=0x0) at xwayland.c:128
#3 xwl_cursor_warped_to (device=<optimized out>, screen=0x268b6e0, client=<optimized out>, window=0x0, sprite=0x300bb30,
x=2400, y=1350) at xwayland.c:292
#4 0x00000000005622ec in ProcWarpPointer (client=0x32755d0) at events.c:3618
In this case, x/y are the screen-space coordinates where the pointer
ends up, and we need to look up the (X) window there.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
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