2001-05-31  Jody Goldberg <jgoldberg@home.com>

	* src/solver-lp.c : Use cell_eval in place of cell_eval_content.

	* src/eval.c (cb_range_hash_invalidate) : disconnect the list from the
	  dep record while removing its contents.  We don't want to modify the
	  list while we are walking it.  This is also an optimization in that
	  we don't need to modify the list.
	(cb_single_hash_invalidate) : ditto.
	(depsingle_dtor) : Ensure that the list has already been cleared.
	(deprange_dtor) : ditto.
	(dependent_unlink) : short circuit if we are destroying.

	* src/sheet.c (sheet_destroy) : Clear the controls first.