case *ast.SelectorExpr:
		if t.X.(*ast.Ident).Name != "unsafe" || t.Sel.Name != "Pointer" {
			log.Fatalf("unhandled type: %#v", t)
		}
		return "types.Types[types.TUNSAFEPTR]"

	case *ast.ArrayType:
		if t.Len == nil {
			return fmt.Sprintf("types.NewSlice(%s)", i.subtype(t.Elt))
		}
		return fmt.Sprintf("types.NewArray(%s, %d)", i.subtype(t.Elt), intconst(t.Len))

	// Materalize expression corresponding to address of the meta-data symbol.
	mdax := typecheck.NodAddr(cnames.MetaVar)
	mdauspx := typecheck.ConvNop(mdax, types.Types[types.TUNSAFEPTR])

	// Materialize expression for length.
	lenx := ir.NewInt(base.Pos, int64(mdlen)) // untyped

	// Generate a call to runtime.addCovMeta, e.g.
	//