PR middle-end/19616
	* tree.h (CALL_EXPR_TAILCALL): Add comment.
	* calls.c (check_sibcall_argument_overlap_1): Revert the change
	to this function from 2004-07-10.
	* tree-tailcall.c (suitable_for_tail_opt_p): Do not consider the
	the current function for tail call optimizations if the address
	of one of it its arguments is taken.

From-SVN: r94265