Via-level design shapes are mapped into stitch regions of line-level design shapes design in an overlying conductive line level. A via-catching design shape is provided in an underlying conductive line level for each stitch region that does not correspond to a via-level design shape. The shapes of the stitch regions and the via-catch design shapes can be adjusted to comply with design rule constraints. Further, stitches can be optionally moved into a neighboring line-level design shape to resolve design rule conflicts. The modified design layout can eliminate via-level design shapes once all via-level design shapes are replaced with a corresponding stitch region, thereby eliminating the need to provide a via level lithographic mask. A metal interconnect structure embodying the modified design layout can be formed by employing a set of hard mask layers and without employing a lithographic mask for a via level.