|| ((start_addr[0] & FIXNUM_TAG_MASK) == 0) /* fixnum */
|| (widetag_of(start_addr[0]) == CHARACTER_WIDETAG)
#if N_WORD_BITS == 64
- || (widetag_of(start_addr[1]) == SINGLE_FLOAT_WIDETAG)
+ || (widetag_of(start_addr[0]) == SINGLE_FLOAT_WIDETAG)
#endif
|| (widetag_of(start_addr[0]) == UNBOUND_MARKER_WIDETAG))
&& (is_lisp_pointer(start_addr[1])