Fixed runaway recursion in cond. However, let is still segfaulting, and member

does not work correctly.

src/memory/conspage.c

@@ -45,6 +45,12 @@ int initialised_cons_pages = 0;
  */
 struct cons_pointer freelist = NIL;
 
+/**
+ * The exception message printed when the world blows up, initialised in
+ * `maybe_bind_init_symbols()` in `init.c`, q.v.
+ */
+struct cons_pointer privileged_string_memory_exhausted;
+
 /**
  * An array of pointers to cons pages.
  */