diff --git a/mozilla/base/src/nsArena.cpp b/mozilla/base/src/nsArena.cpp
index a38ef687f58..d0ed8804bfa 100644
--- a/mozilla/base/src/nsArena.cpp
+++ b/mozilla/base/src/nsArena.cpp
@@ -33,7 +33,7 @@ public:
   virtual void* Alloc(PRInt32 aSize);
 
 protected:
-  ~ArenaImpl();
+  virtual ~ArenaImpl();
 
   PLArenaPool mPool;
   PRInt32 mBlockSize;
diff --git a/mozilla/base/src/nsAtomTable.cpp b/mozilla/base/src/nsAtomTable.cpp
index 4704ad1c119..fda308213fd 100644
--- a/mozilla/base/src/nsAtomTable.cpp
+++ b/mozilla/base/src/nsAtomTable.cpp
@@ -30,7 +30,7 @@ static struct PLHashTable* gAtomHashTable;
 class AtomImpl : public nsIAtom {
 public:
   AtomImpl();
-  ~AtomImpl();
+  virtual ~AtomImpl();
 
   NS_DECL_ISUPPORTS
 
diff --git a/mozilla/base/src/nsByteBuffer.cpp b/mozilla/base/src/nsByteBuffer.cpp
index c2e66937483..ed3bbc37b75 100644
--- a/mozilla/base/src/nsByteBuffer.cpp
+++ b/mozilla/base/src/nsByteBuffer.cpp
@@ -24,7 +24,7 @@
 class ByteBufferImpl : public nsIByteBuffer {
 public:
   ByteBufferImpl(PRUint32 aBufferSize);
-  ~ByteBufferImpl();
+  virtual ~ByteBufferImpl();
 
   NS_DECL_ISUPPORTS
   NS_IMETHOD_(PRUint32) GetLength(void) const;
diff --git a/mozilla/base/src/nsObserver.h b/mozilla/base/src/nsObserver.h
index cf8eef47f9a..4d5a646cc26 100644
--- a/mozilla/base/src/nsObserver.h
+++ b/mozilla/base/src/nsObserver.h
@@ -28,7 +28,7 @@ public:
     NS_IMETHOD   Notify(nsISupports** result);
  
     nsObserver();
-    ~nsObserver(void);
+    virtual ~nsObserver(void);
      
     NS_DECL_ISUPPORTS
 
diff --git a/mozilla/base/src/nsObserverList.h b/mozilla/base/src/nsObserverList.h
index eb4442b259b..6228880a8d1 100644
--- a/mozilla/base/src/nsObserverList.h
+++ b/mozilla/base/src/nsObserverList.h
@@ -33,7 +33,7 @@ public:
 	NS_IMETHOD EnumerateObserverList(nsIEnumerator** anEnumerator);
 
     nsObserverList();
-    ~nsObserverList(void);
+    virtual ~nsObserverList(void);
 
     // This is ObserverList monitor object.
     PRLock* mLock;
diff --git a/mozilla/base/src/nsObserverService.cpp b/mozilla/base/src/nsObserverService.cpp
index 6a0fb81d8f1..13402b8c4b5 100644
--- a/mozilla/base/src/nsObserverService.cpp
+++ b/mozilla/base/src/nsObserverService.cpp
@@ -45,7 +45,7 @@ public:
 
    
     nsObserverService();
-    ~nsObserverService(void);
+    virtual ~nsObserverService(void);
      
     NS_DECL_ISUPPORTS
 
diff --git a/mozilla/base/src/nsSizeOfHandler.cpp b/mozilla/base/src/nsSizeOfHandler.cpp
index c15a435437c..63ee1ac4a85 100644
--- a/mozilla/base/src/nsSizeOfHandler.cpp
+++ b/mozilla/base/src/nsSizeOfHandler.cpp
@@ -23,7 +23,7 @@ static NS_DEFINE_IID(kISizeOfHandlerIID, NS_ISIZEOF_HANDLER_IID);
 class nsSizeOfHandler : public nsISizeOfHandler {
 public:
   nsSizeOfHandler();
-  ~nsSizeOfHandler();
+  virtual ~nsSizeOfHandler();
 
   // nsISupports
   NS_DECL_ISUPPORTS
diff --git a/mozilla/base/src/nsUnicharBuffer.cpp b/mozilla/base/src/nsUnicharBuffer.cpp
index 961be5e626c..4e2b338513f 100644
--- a/mozilla/base/src/nsUnicharBuffer.cpp
+++ b/mozilla/base/src/nsUnicharBuffer.cpp
@@ -24,7 +24,7 @@
 class UnicharBufferImpl : public nsIUnicharBuffer {
 public:
   UnicharBufferImpl(PRUint32 aBufferSize);
-  ~UnicharBufferImpl();
+  virtual ~UnicharBufferImpl();
 
   NS_DECL_ISUPPORTS
   virtual PRInt32 GetLength() const;
diff --git a/mozilla/base/src/nsUnicharInputStream.cpp b/mozilla/base/src/nsUnicharInputStream.cpp
index 2efaffb3de3..23f3bdd6b21 100644
--- a/mozilla/base/src/nsUnicharInputStream.cpp
+++ b/mozilla/base/src/nsUnicharInputStream.cpp
@@ -37,7 +37,7 @@ static NS_DEFINE_IID(kIUnicharInputStreamIID, NS_IUNICHAR_INPUT_STREAM_IID);
 class StringUnicharInputStream : public nsIUnicharInputStream {
 public:
   StringUnicharInputStream(nsString* aString);
-  ~StringUnicharInputStream();
+  virtual ~StringUnicharInputStream();
 
   NS_DECL_ISUPPORTS
 
@@ -159,7 +159,7 @@ public:
   ConverterInputStream(nsIInputStream* aStream,
                        nsIUnicodeDecoder* aConverter,
                        PRUint32 aBufSize);
-  ~ConverterInputStream();
+  virtual ~ConverterInputStream();
 
   NS_DECL_ISUPPORTS
   NS_IMETHOD Read(PRUnichar* aBuf,
diff --git a/mozilla/xpcom/ds/nsArena.cpp b/mozilla/xpcom/ds/nsArena.cpp
index a38ef687f58..d0ed8804bfa 100644
--- a/mozilla/xpcom/ds/nsArena.cpp
+++ b/mozilla/xpcom/ds/nsArena.cpp
@@ -33,7 +33,7 @@ public:
   virtual void* Alloc(PRInt32 aSize);
 
 protected:
-  ~ArenaImpl();
+  virtual ~ArenaImpl();
 
   PLArenaPool mPool;
   PRInt32 mBlockSize;
diff --git a/mozilla/xpcom/ds/nsAtomTable.cpp b/mozilla/xpcom/ds/nsAtomTable.cpp
index 4704ad1c119..fda308213fd 100644
--- a/mozilla/xpcom/ds/nsAtomTable.cpp
+++ b/mozilla/xpcom/ds/nsAtomTable.cpp
@@ -30,7 +30,7 @@ static struct PLHashTable* gAtomHashTable;
 class AtomImpl : public nsIAtom {
 public:
   AtomImpl();
-  ~AtomImpl();
+  virtual ~AtomImpl();
 
   NS_DECL_ISUPPORTS
 
diff --git a/mozilla/xpcom/ds/nsByteBuffer.cpp b/mozilla/xpcom/ds/nsByteBuffer.cpp
index c2e66937483..ed3bbc37b75 100644
--- a/mozilla/xpcom/ds/nsByteBuffer.cpp
+++ b/mozilla/xpcom/ds/nsByteBuffer.cpp
@@ -24,7 +24,7 @@
 class ByteBufferImpl : public nsIByteBuffer {
 public:
   ByteBufferImpl(PRUint32 aBufferSize);
-  ~ByteBufferImpl();
+  virtual ~ByteBufferImpl();
 
   NS_DECL_ISUPPORTS
   NS_IMETHOD_(PRUint32) GetLength(void) const;
diff --git a/mozilla/xpcom/ds/nsObserver.h b/mozilla/xpcom/ds/nsObserver.h
index cf8eef47f9a..4d5a646cc26 100644
--- a/mozilla/xpcom/ds/nsObserver.h
+++ b/mozilla/xpcom/ds/nsObserver.h
@@ -28,7 +28,7 @@ public:
     NS_IMETHOD   Notify(nsISupports** result);
  
     nsObserver();
-    ~nsObserver(void);
+    virtual ~nsObserver(void);
      
     NS_DECL_ISUPPORTS
 
diff --git a/mozilla/xpcom/ds/nsObserverList.h b/mozilla/xpcom/ds/nsObserverList.h
index eb4442b259b..6228880a8d1 100644
--- a/mozilla/xpcom/ds/nsObserverList.h
+++ b/mozilla/xpcom/ds/nsObserverList.h
@@ -33,7 +33,7 @@ public:
 	NS_IMETHOD EnumerateObserverList(nsIEnumerator** anEnumerator);
 
     nsObserverList();
-    ~nsObserverList(void);
+    virtual ~nsObserverList(void);
 
     // This is ObserverList monitor object.
     PRLock* mLock;
diff --git a/mozilla/xpcom/ds/nsObserverService.cpp b/mozilla/xpcom/ds/nsObserverService.cpp
index 6a0fb81d8f1..13402b8c4b5 100644
--- a/mozilla/xpcom/ds/nsObserverService.cpp
+++ b/mozilla/xpcom/ds/nsObserverService.cpp
@@ -45,7 +45,7 @@ public:
 
    
     nsObserverService();
-    ~nsObserverService(void);
+    virtual ~nsObserverService(void);
      
     NS_DECL_ISUPPORTS
 
diff --git a/mozilla/xpcom/ds/nsSizeOfHandler.cpp b/mozilla/xpcom/ds/nsSizeOfHandler.cpp
index c15a435437c..63ee1ac4a85 100644
--- a/mozilla/xpcom/ds/nsSizeOfHandler.cpp
+++ b/mozilla/xpcom/ds/nsSizeOfHandler.cpp
@@ -23,7 +23,7 @@ static NS_DEFINE_IID(kISizeOfHandlerIID, NS_ISIZEOF_HANDLER_IID);
 class nsSizeOfHandler : public nsISizeOfHandler {
 public:
   nsSizeOfHandler();
-  ~nsSizeOfHandler();
+  virtual ~nsSizeOfHandler();
 
   // nsISupports
   NS_DECL_ISUPPORTS
diff --git a/mozilla/xpcom/ds/nsUnicharBuffer.cpp b/mozilla/xpcom/ds/nsUnicharBuffer.cpp
index 961be5e626c..4e2b338513f 100644
--- a/mozilla/xpcom/ds/nsUnicharBuffer.cpp
+++ b/mozilla/xpcom/ds/nsUnicharBuffer.cpp
@@ -24,7 +24,7 @@
 class UnicharBufferImpl : public nsIUnicharBuffer {
 public:
   UnicharBufferImpl(PRUint32 aBufferSize);
-  ~UnicharBufferImpl();
+  virtual ~UnicharBufferImpl();
 
   NS_DECL_ISUPPORTS
   virtual PRInt32 GetLength() const;
diff --git a/mozilla/xpcom/io/nsUnicharInputStream.cpp b/mozilla/xpcom/io/nsUnicharInputStream.cpp
index 2efaffb3de3..23f3bdd6b21 100644
--- a/mozilla/xpcom/io/nsUnicharInputStream.cpp
+++ b/mozilla/xpcom/io/nsUnicharInputStream.cpp
@@ -37,7 +37,7 @@ static NS_DEFINE_IID(kIUnicharInputStreamIID, NS_IUNICHAR_INPUT_STREAM_IID);
 class StringUnicharInputStream : public nsIUnicharInputStream {
 public:
   StringUnicharInputStream(nsString* aString);
-  ~StringUnicharInputStream();
+  virtual ~StringUnicharInputStream();
 
   NS_DECL_ISUPPORTS
 
@@ -159,7 +159,7 @@ public:
   ConverterInputStream(nsIInputStream* aStream,
                        nsIUnicodeDecoder* aConverter,
                        PRUint32 aBufSize);
-  ~ConverterInputStream();
+  virtual ~ConverterInputStream();
 
   NS_DECL_ISUPPORTS
   NS_IMETHOD Read(PRUnichar* aBuf,