diff --git a/src/script_opt/Expr.cc b/src/script_opt/Expr.cc
index 3af06df5cd..da42ac46db 100644
--- a/src/script_opt/Expr.cc
+++ b/src/script_opt/Expr.cc
@@ -369,7 +369,7 @@ ExprPtr NameExpr::Reduce(Reducer* c, StmtPtr& red_stmt)
 		return TransformMe(make_intrusive<ConstExpr>(v), c, red_stmt);
 		}
 
-	return c->UpdateName(this)->ThisPtr();
+	return c->UpdateName({NewRef{}, this});
 	}
 
 ValPtr NameExpr::FoldVal() const
diff --git a/src/script_opt/Reduce.cc b/src/script_opt/Reduce.cc
index 5e7adb7e41..b30c669882 100644
--- a/src/script_opt/Reduce.cc
+++ b/src/script_opt/Reduce.cc
@@ -33,15 +33,12 @@ ExprPtr Reducer::GenTemporaryExpr(const TypePtr& t, ExprPtr rhs)
 	return e;
 	}
 
-NameExpr* Reducer::UpdateName(NameExpr* n)
+NameExprPtr Reducer::UpdateName(NameExprPtr n)
 	{
-	if ( NameIsReduced(n) )
-		{
-		Ref(n);
+	if ( NameIsReduced(n.get()) )
 		return n;
-		}
 
-	return new NameExpr(FindNewLocal(n));
+	return make_intrusive<NameExpr>(FindNewLocal(n.get()));
 	}
 
 bool Reducer::NameIsReduced(const NameExpr* n) const
@@ -58,7 +55,10 @@ void Reducer::UpdateIDs(IDPList* ids)
 		IDPtr id = {NewRef{}, (*ids)[i]};
 
 		if ( ! ID_IsReduced(id) )
+			{
+			Unref((*ids)[i]);
 			(*ids)[i] = UpdateID(id).release();
+			}
 		}
 	}
 
@@ -198,7 +198,7 @@ TempVar* Reducer::FindTemporary(const ID* id) const
 		return tmp->second;
 	}
 
-Stmt* Reducer::MergeStmts(const NameExpr* lhs, ExprPtr rhs, Stmt* succ_stmt)
+StmtPtr Reducer::MergeStmts(const NameExpr* lhs, ExprPtr rhs, Stmt* succ_stmt)
 	{
 	// First check for tmp=rhs.
 	auto lhs_id = lhs->Id();
@@ -254,7 +254,7 @@ Stmt* Reducer::MergeStmts(const NameExpr* lhs, ExprPtr rhs, Stmt* succ_stmt)
 						nullptr, nullptr, false);
 	TrackExprReplacement(rhs.get(), merge_e.get());
 
-	return new ExprStmt(merge_e);
+	return make_intrusive<ExprStmt>(merge_e);
 	}
                  
 void Reducer::TrackExprReplacement(const Expr* orig, const Expr* e)
diff --git a/src/script_opt/Reduce.h b/src/script_opt/Reduce.h
index 9f82eba2b0..51214d6e01 100644
--- a/src/script_opt/Reduce.h
+++ b/src/script_opt/Reduce.h
@@ -25,7 +25,7 @@ public:
 
 	ExprPtr GenTemporaryExpr(const TypePtr& t, ExprPtr rhs);
 
-	NameExpr* UpdateName(NameExpr* n);
+	NameExprPtr UpdateName(NameExprPtr n);
 	bool NameIsReduced(const NameExpr* n) const;
 
 	void UpdateIDs(IDPList* ids);
@@ -105,7 +105,7 @@ public:
 	// Given an lhs=rhs statement followed by succ_stmt, returns
 	// a (new) merge of the two if they're of the form tmp=rhs, var=tmp;
 	// otherwise, nil.
-	Stmt* MergeStmts(const NameExpr* lhs, ExprPtr rhs, Stmt* succ_stmt);
+	StmtPtr MergeStmts(const NameExpr* lhs, ExprPtr rhs, Stmt* succ_stmt);
 
 	// The following two methods will, in the future, update expressions
 	// with optimized versions.  They are distinct because the first
diff --git a/src/script_opt/Stmt.cc b/src/script_opt/Stmt.cc
index 9b9f5b7f4c..9f61aaa4fd 100644
--- a/src/script_opt/Stmt.cc
+++ b/src/script_opt/Stmt.cc
@@ -845,7 +845,7 @@ bool StmtList::ReduceStmt(int& s_i, StmtPList* f_stmts, Reducer* c)
 			auto merge = c->MergeStmts(var, rhs, s_i_succ);
 			if ( merge )
 				{
-				f_stmts->append(merge);
+				f_stmts->append(merge.release());
 
 				// Skip both this statement and the next,
 				// now that we've substituted the merge.