From 5df6ffd9480f0f0165bbc752e16c38cffd206527 Mon Sep 17 00:00:00 2001
From: Nick Lewycky <nicholas@mxc.ca>
Date: Mon, 14 Sep 2009 02:25:19 +0000
Subject: [PATCH] Fifth time's a charm! Remove ourselves as abstract type
 listeners once we've been told that the type is no longer abstract.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81749 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/VMCore/Verifier.cpp | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/lib/VMCore/Verifier.cpp b/lib/VMCore/Verifier.cpp
index 7b2afde0a0e..140e6bd8b15 100644
--- a/lib/VMCore/Verifier.cpp
+++ b/lib/VMCore/Verifier.cpp
@@ -107,8 +107,9 @@ PreVer("preverify", "Preliminary module verification");
 static const PassInfo *const PreVerifyID = &PreVer;
 
 namespace {
-  struct TypeSet : public AbstractTypeUser {
-    SmallSetVector<const Type *, 16> Types;
+  class TypeSet : public AbstractTypeUser {
+  public:
+    TypeSet() {}
 
     /// Insert a type into the set of types.
     bool insert(const Type *Ty) {
@@ -138,8 +139,20 @@ namespace {
       Types.remove(OldTy);
       OldTy->removeAbstractTypeUser(this);
     }
-    void typeBecameConcrete(const DerivedType *AbsTy) {}
+
+    /// Stop listening for changes to a type which is no longer abstract.
+    void typeBecameConcrete(const DerivedType *AbsTy) {
+      AbsTy->removeAbstractTypeUser(this);
+    }
+
     void dump() const {}
+
+  private:
+    SmallSetVector<const Type *, 16> Types;
+
+    // Disallow copying.
+    TypeSet(const TypeSet &);
+    TypeSet &operator=(const TypeSet &);
   };
 
   struct Verifier : public FunctionPass, public InstVisitor<Verifier> {