/* Get rid of any bits that would cause confusion. */
XVECTOR (val)->size = 0; /* No Lisp_Object to trace in there. */
+ /* Use XVECTOR (val) rather than `p' because p->size is not TRT. */
XSETPVECTYPE (XVECTOR (val), PVEC_BOOL_VECTOR);
p = XBOOL_VECTOR (val);