* gfortran.h (gfc_equiv_info): Add length field.
	* trans-common.c (copy_equiv_list_to_ns): Set the length field.
	* dependency.c (gfc_are_equivalenced_arrays): Use both the offset
	and length fields to determine whether the two equivalenced symbols
	overlap in memory.

	* gfortran.dg/dependency_13.f90: New test case.

From-SVN: r112162