> Sounds like a duplicate of bug #21732.
 >
 >> With these steps, I get this backtrace:
 >>
 >>    Debugger entered--Lisp error: (wrong-type-argument wholenump -14)
 >>      posn-at-point(619194 #)

Without further forensics we could "fix" both bugs using the attached
patch.  WDYT?

martin