From d636a1da626ad492864aa1758af3f0caad1ea488 Mon Sep 17 00:00:00 2001
From: Chris Dodd <chris@barefootnetworks.com>
Date: Tue, 7 Mar 2017 10:55:32 -0800
Subject: [PATCH] clean up override warning for NDEBUG builds

---
 ir/visitor.cpp | 11 +++++++----
 ir/visitor.h   | 11 ++++-------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/ir/visitor.cpp b/ir/visitor.cpp
index d07544f2015..f88d2ad8649 100644
--- a/ir/visitor.cpp
+++ b/ir/visitor.cpp
@@ -344,21 +344,24 @@ bool ControlFlowVisitor::join_flows(const IR::Node *n) {
     return false;
 }
 
-void Inspector::check_clone(const Visitor *v) {
+bool Inspector::check_clone(const Visitor *v) {
     auto *t = dynamic_cast<const Inspector *>(v);
     BUG_CHECK(t && t->visited == visited, "Clone failed to copy base object");
+    return true;
 }
-void Modifier::check_clone(const Visitor *v) {
+bool Modifier::check_clone(const Visitor *v) {
     auto *t = dynamic_cast<const Modifier *>(v);
     BUG_CHECK(t && t->visited == visited, "Clone failed to copy base object");
+    return true;
 }
-void Transform::check_clone(const Visitor *v) {
+bool Transform::check_clone(const Visitor *v) {
     auto *t = dynamic_cast<const Transform *>(v);
     BUG_CHECK(t && t->visited == visited, "Clone failed to copy base object");
+    return true;
 }
 
 ControlFlowVisitor &ControlFlowVisitor::flow_clone() {
     auto *rv = clone();
-    rv->check_clone(this);
+    assert(rv->check_clone(this));
     return *rv;
 }
diff --git a/ir/visitor.h b/ir/visitor.h
index ad38f6fe7c0..06220968901 100644
--- a/ir/visitor.h
+++ b/ir/visitor.h
@@ -165,10 +165,7 @@ class Visitor {
     virtual bool join_flows(const IR::Node *) { return false; }
     void visit_children(const IR::Node *, std::function<void()> fn) { fn(); }
     class ChangeTracker;  // used by Modifier and Transform -- private to them
-#ifndef NDEBUG
-    virtual  // making this non-virtual for NDEBUG builds turns it into a noop
-#endif
-    void check_clone(const Visitor *) {}
+    virtual bool check_clone(const Visitor *) { return true; }
 
  private:
     virtual void visitor_const_error();
@@ -182,7 +179,7 @@ class Visitor {
 class Modifier : public virtual Visitor {
     ChangeTracker       *visited = nullptr;
     void visitor_const_error() override;
-    void check_clone(const Visitor *) override;
+    bool check_clone(const Visitor *) override;
  public:
     profile_t init_apply(const IR::Node *root) override;
     const IR::Node *apply_visitor(const IR::Node *n, const char *name = 0) override;
@@ -201,7 +198,7 @@ class Modifier : public virtual Visitor {
 class Inspector : public virtual Visitor {
     typedef unordered_map<const IR::Node *, bool>       visited_t;
     visited_t   *visited = nullptr;
-    void check_clone(const Visitor *) override;
+    bool check_clone(const Visitor *) override;
  public:
     profile_t init_apply(const IR::Node *root) override;
     const IR::Node *apply_visitor(const IR::Node *, const char *name = 0) override;
@@ -221,7 +218,7 @@ class Transform : public virtual Visitor {
     ChangeTracker       *visited = nullptr;
     bool prune_flag = false;
     void visitor_const_error() override;
-    void check_clone(const Visitor *) override;
+    bool check_clone(const Visitor *) override;
 
  public:
     profile_t init_apply(const IR::Node *root) override;