* trans-stmt.c (forall_info): Replace the next_nest and outer
	fields that previously implemented a doubly-linked list with a
	single prev_nest field (singly-linked list).
	(gfc_trans_nested_forall_loop): The nested_forall_info argument
	now denotes the innermost FORALL in the loop nest.
	(compute_overall_iter_number): Use prev_nest instead of next_nest.
	(gfc_trans_forall_1): Link/cons the new "info" to the head of the
	nested_forall_info linked list.  Free the current "info" when done.

	* gfortran.dg/forall_7.f90: New test case.

From-SVN: r121236