+lispobj *search_read_only_space(void *pointer);
+lispobj *search_static_space(void *pointer);
+lispobj *search_dynamic_space(void *pointer);
+
+/* Scan an area looking for an object which encloses the given pointer.
+ * Return the object start on success or NULL on failure. */
+static lispobj *
+search_space(lispobj *start, size_t words, lispobj *pointer)
+{
+ while (words > 0) {
+ size_t count = 1;
+ lispobj thing = *start;
+
+ /* If thing is an immediate then this is a cons. */
+ if (is_lisp_pointer(thing)
+ || ((thing & 3) == 0) /* fixnum */
+ || (widetag_of(thing) == BASE_CHAR_WIDETAG)
+ || (widetag_of(thing) == UNBOUND_MARKER_WIDETAG))
+ count = 2;
+ else
+ count = (sizetab[widetag_of(thing)])(start);
+
+ /* Check whether the pointer is within this object. */
+ if ((pointer >= start) && (pointer < (start+count))) {
+ /* found it! */
+ /*FSHOW((stderr,"/found %x in %x %x\n", pointer, start, thing));*/
+ return(start);
+ }
+
+ /* Round up the count. */
+ count = CEILING(count,2);
+
+ start += count;
+ words -= count;
+ }
+ return (NULL);
+}
+