diff --git a/dag/new.txt b/dag/new.txt
new file mode 100644
index 000000000000..60cb268d4849
--- /dev/null
+++ b/dag/new.txt
@@ -0,0 +1,6 @@
+goos: darwin
+goarch: amd64
+pkg: github.com/hashicorp/terraform/dag
+BenchmarkDAG-4   	       2	11022154016 ns/op	2049244080 B/op	61428144 allocs/op
+PASS
+ok  	github.com/hashicorp/terraform/dag	35.729s
diff --git a/dag/old.txt b/dag/old.txt
new file mode 100644
index 000000000000..d9441ccde2b2
--- /dev/null
+++ b/dag/old.txt
@@ -0,0 +1,6 @@
+goos: darwin
+goarch: amd64
+pkg: github.com/hashicorp/terraform/dag
+BenchmarkDAG-4   	       1	66577406455 ns/op	5917501632 B/op	576835287 allocs/op
+PASS
+ok  	github.com/hashicorp/terraform/dag	68.575s
diff --git a/diagsvet b/diagsvet
new file mode 100755
index 000000000000..b659c583ec7b
Binary files /dev/null and b/diagsvet differ
diff --git a/diagsvet.go b/diagsvet.go
new file mode 100644
index 000000000000..c8933476ddb4
--- /dev/null
+++ b/diagsvet.go
@@ -0,0 +1,74 @@
+// +build ignore
+
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"strings"
+
+	"github.com/hashicorp/terraform/tfdiags"
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/inspect"
+	"golang.org/x/tools/go/analysis/unitchecker"
+	"golang.org/x/tools/go/ast/inspector"
+)
+
+var Analyzer = &analysis.Analyzer{
+	Name:     "diags",
+	Doc:      "check for diagnostic assignments to error variables",
+	Requires: []*analysis.Analyzer{inspect.Analyzer},
+	Run:      run,
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+
+	nodeFilter := []ast.Node{
+		(*ast.AssignStmt)(nil),
+	}
+	inspect.Preorder(nodeFilter, func(n ast.Node) {
+		stmt := n.(*ast.AssignStmt)
+		if stmt.Tok != token.DEFINE {
+			return // ignore =
+		}
+
+		err := tfdiags.Diagnostics{}
+		if err != nil {
+		}
+
+		for _, x := range stmt.Lhs {
+			id, isId := x.(*ast.Ident)
+			if !isId {
+				continue
+			}
+
+			// any e, err, myErr, etc
+			if !(id.Name == "e" || strings.Contains(id.Name, "err") || strings.Contains(id.Name, "Err")) {
+				continue
+			}
+
+			def := pass.TypesInfo.Defs[id]
+			if def == nil {
+				continue
+			}
+			named, ok := def.Type().(*types.Named)
+			if !ok {
+				continue
+			}
+			typeName := named.Obj().Name()
+
+			if strings.HasPrefix(typeName, "Diagnostic") {
+				pass.Reportf(stmt.Pos(), fmt.Sprintf("%s type assigned to variable named %q", typeName, id.Name))
+			}
+		}
+	})
+
+	return nil, nil
+}
+
+func main() {
+	unitchecker.Main(Analyzer)
+}
diff --git a/terraform/node_resource_destroy.go b/terraform/node_resource_destroy.go
index c5042436dde4..4e495cbcb900 100644
--- a/terraform/node_resource_destroy.go
+++ b/terraform/node_resource_destroy.go
@@ -282,12 +282,28 @@ type NodeDestroyResource struct {
 
 var (
 	_ GraphNodeEvalable = (*NodeDestroyResource)(nil)
+	// TransformReferences looks for indirect references as well, and relies
+	// on these two interfaces to connect them.
+	_ GraphNodeReferenceable = (*NodeDestroyResource)(nil)
+	_ GraphNodeSubPath       = (*NodeDestroyResource)(nil)
 )
 
 func (n *NodeDestroyResource) Name() string {
 	return n.NodeAbstractResource.ResourceAddr().String() + " (clean up state)"
 }
 
+// NodeDestroyResource still needs to be a GraphNodeReferenceable so that a
+// NodeModuleRemoved can reference it for cleanup.
+func (n *NodeDestroyResource) ReferenceableAddrs() []addrs.Referenceable {
+	return n.NodeAbstractResource.ReferenceableAddrs()
+}
+
+// NodeDestroyResource still needs to be a GraphNodeSubPath so that a
+// NodeModuleRemoved can reference it for cleanup.
+func (n *NodeDestroyResource) Path() addrs.ModuleInstance {
+	return n.NodeAbstractResource.Path()
+}
+
 // GraphNodeEvalable
 func (n *NodeDestroyResource) EvalTree() EvalNode {
 	// This EvalNode will produce an error if the resource isn't already