Allow assignment of an empty variable to an empty indexing slice (bug #45467). * Array.cc (Array<T>::assign): For 2-D case, check that neither the LHS or RHS is empty before calling gripe_assignment_dimension_mismatch(). * Array.cc (Array<T>::assign): For N-D case, check that neither the LHS or RHS is empty before calling gripe_assignment_dimension_mismatch().

7f19e7f2afa2b1476983003f9cd6df2f5b2a4b08 gnulib-hg