gfortran.h (gfc_symbol): Add a new "forall_index" bit field.

gfortran.h (gfc_symbol): Add a new "forall_index" bit field.

	* gfortran.h (gfc_symbol): Add a new "forall_index" bit field.
	* match.c (match_forall_iterator): Set forall_index field on
	the iteration variable's symbol.
	* dependency.c (contains_forall_index_p): New function to
	traverse a gfc_expr to check whether it contains a variable
	with forall_index set in it's symbol.
	(gfc_check_element_vs_element): Return GFC_DEP_EQUAL for scalar
	constant expressions that don't variables used as FORALL indices.

	* gfortran.dg/dependency_9.f90: New (resurected) test case.

From-SVN: r112373