merge pyk-TclOO

7 files changed, 326 insertions, 431 deletions

diff --git a/generic/tclBasic.c b/generic/tclBasic.c
index 5000821..3fb099b 100644
--- a/generic/tclBasic.c
+++ b/generic/tclBasic.c
@@ -3136,6 +3136,7 @@ Tcl_DeleteCommandFromToken(
      */
 
     cmdPtr->nsPtr->refCount++;
+
     if (cmdPtr->tracePtr != NULL) {
 	CommandTrace *tracePtr;
 	CallCommandTraces(iPtr,cmdPtr,NULL,NULL,TCL_TRACE_DELETE);
diff --git a/generic/tclOO.c b/generic/tclOO.c
index 87ed649..c6ea91d 100644
--- a/generic/tclOO.c
+++ b/generic/tclOO.c
@@ -59,8 +59,6 @@ static const struct {
 static Class *		AllocClass(Tcl_Interp *interp, Object *useThisObj);
 static Object *		AllocObject(Tcl_Interp *interp, const char *nameStr,
 			    Namespace *nsPtr, const char *nsNameStr);
-static void		ClearMixins(Class *clsPtr);
-static void		ClearSuperclasses(Class *clsPtr);
 static int		CloneClassMethod(Tcl_Interp *interp, Class *clsPtr,
 			    Method *mPtr, Tcl_Obj *namePtr,
 			    Method **newMPtrPtr);
@@ -72,6 +70,7 @@ static void		DeletedHelpersNamespace(ClientData clientData);
 static Tcl_NRPostProc	FinalizeAlloc;
 static Tcl_NRPostProc	FinalizeNext;
 static Tcl_NRPostProc	FinalizeObjectCall;
+static void		initClassPath(Tcl_Interp * interp, Class *clsPtr);
 static int		InitFoundation(Tcl_Interp *interp);
 static void		KillFoundation(ClientData clientData,
 			    Tcl_Interp *interp);
@@ -81,6 +80,7 @@ static void		ObjectRenamedTrace(ClientData clientData,
 			    Tcl_Interp *interp, const char *oldName,
 			    const char *newName, int flags);
 static void		ReleaseClassContents(Tcl_Interp *interp,Object *oPtr);
+static void		DeleteDescendants(Tcl_Interp *interp,Object *oPtr);
 static inline void	SquelchCachedName(Object *oPtr);
 
 static int		PublicObjectCmd(ClientData clientData,
@@ -95,6 +95,8 @@ static int		PrivateObjectCmd(ClientData clientData,
 static int		PrivateNRObjectCmd(ClientData clientData,
 			    Tcl_Interp *interp, int objc,
 			    Tcl_Obj *const *objv);
+static void		RemoveClass(Class ** list, int num, int idx);
+static void		RemoveObject(Object ** list, int num, int idx);
 
 /*
  * Methods in the oo::object and oo::class classes. First, we define a helper
@@ -227,10 +229,16 @@ MODULE_SCOPE const TclOOStubs tclOOStubs;
  * ROOT_CLASS respectively.
  */
 
-#define Deleted(oPtr)		(((Object *)(oPtr))->command == NULL)
+#define Deleted(oPtr)		((oPtr)->flags & OBJECT_DELETED)
 #define IsRootObject(ocPtr)	((ocPtr)->flags & ROOT_OBJECT)
 #define IsRootClass(ocPtr)	((ocPtr)->flags & ROOT_CLASS)
 #define IsRoot(ocPtr)		((ocPtr)->flags & (ROOT_OBJECT|ROOT_CLASS))
+
+#define RemoveItem(type, lst, i) \
+    do { \
+	Remove ## type ((lst).list, (lst).num, i); \
+	(lst).num--; \
+    } while (0)
 
 /*
  * ----------------------------------------------------------------------
@@ -312,6 +320,10 @@ InitFoundation(
 	    Tcl_GetThreadData(&tsdKey, sizeof(ThreadLocalData));
     Foundation *fPtr = ckalloc(sizeof(Foundation));
     Tcl_Obj *namePtr, *argsPtr, *bodyPtr;
+
+    Class fakeCls;
+    Object fakeObject;
+
     Tcl_DString buffer;
     Command *cmdPtr;
     int i;
@@ -378,24 +390,43 @@ InitFoundation(
      * spliced manually.
      */
 
+    /* Stand up a phony class for bootstrapping. */
+    fPtr->objectCls = &fakeCls;
+    /* referenced in AllocClass to increment the refCount. */
+    fakeCls.thisPtr = &fakeObject;
+
     fPtr->objectCls = AllocClass(interp,
 	    AllocObject(interp, "object", (Namespace *)fPtr->ooNs, NULL));
     fPtr->classCls = AllocClass(interp,
 	    AllocObject(interp, "class", (Namespace *)fPtr->ooNs, NULL));
+
+    /* Rewire bootstrapped objects. */
     fPtr->objectCls->thisPtr->selfCls = fPtr->classCls;
+    fPtr->classCls->thisPtr->selfCls = fPtr->classCls;
+
+    AddRef(fPtr->objectCls->thisPtr);
+    AddRef(fPtr->classCls->thisPtr);
+    AddRef(fPtr->classCls->thisPtr->selfCls->thisPtr);
+    AddRef(fPtr->objectCls->thisPtr->selfCls->thisPtr);
+
+    /* special initialization for the primordial objects */
     fPtr->objectCls->thisPtr->flags |= ROOT_OBJECT;
     fPtr->objectCls->flags |= ROOT_OBJECT;
+
+    /* This is why it is unnecessary in this routine to make up for the
+     * incremented reference count of fPtr->objectCls that was sallwed by
+     * fakeObject. */
     fPtr->objectCls->superclasses.num = 0;
     ckfree(fPtr->objectCls->superclasses.list);
     fPtr->objectCls->superclasses.list = NULL;
-    fPtr->classCls->thisPtr->selfCls = fPtr->classCls;
+
     fPtr->classCls->thisPtr->flags |= ROOT_CLASS;
     fPtr->classCls->flags |= ROOT_CLASS;
+
+    /* Standard initialization for new Objects */
     TclOOAddToInstances(fPtr->objectCls->thisPtr, fPtr->classCls);
     TclOOAddToInstances(fPtr->classCls->thisPtr, fPtr->classCls);
     TclOOAddToSubclasses(fPtr->classCls, fPtr->objectCls);
-    AddRef(fPtr->objectCls->thisPtr);
-    AddRef(fPtr->objectCls);
 
     /*
      * Basic method declarations for the core classes.
@@ -521,8 +552,6 @@ KillFoundation(
 {
     Foundation *fPtr = GetFoundation(interp);
 
-    DelRef(fPtr->objectCls->thisPtr);
-    DelRef(fPtr->objectCls);
     TclDecrRefCount(fPtr->unknownMethodNameObj);
     TclDecrRefCount(fPtr->constructorName);
     TclDecrRefCount(fPtr->destructorName);
@@ -537,8 +566,11 @@ KillFoundation(
  * AllocObject --
  *
  *	Allocate an object of basic type. Does not splice the object into its
- *	class's instance list.  The caller must set the classPtr on the object,
- *	either to a class or to NULL.
+ *	class's instance list.  The caller must set the classPtr on the object
+ *	to either a class or NULL, call TclOOAddToInstances to add the object
+ *	to the class's instance list, and if the object itself is a class, use
+ *	call TclOOAddToSubclasses() to add it to the right class's list of
+ *	subclasses.
  *
  * ----------------------------------------------------------------------
  */
@@ -563,7 +595,7 @@ AllocObject(
     Object *oPtr;
     Command *cmdPtr;
     CommandTrace *tracePtr;
-    int creationEpoch, ignored;
+    int creationEpoch;
 
     oPtr = ckalloc(sizeof(Object));
     memset(oPtr, 0, sizeof(Object));
@@ -640,9 +672,15 @@ AllocObject(
      */
 
     oPtr->fPtr = fPtr;
-    oPtr->selfCls = fPtr->objectCls;
     oPtr->creationEpoch = creationEpoch;
-    oPtr->refCount = 1;
+
+    /*
+     * An object starts life with a refCount of 2 to mark the two stages of
+     * destruction it occur:  A call to ObjectRenamedTrace(), and a call to
+     * ObjectNamespaceDeleted(). 
+     */
+    oPtr->refCount = 2;
+
     oPtr->flags = USE_CLASS_CACHE;
 
     /*
@@ -654,6 +692,10 @@ AllocObject(
     if (!nameStr) {
 	nameStr = oPtr->namespacePtr->name;
 	nsPtr = (Namespace *)oPtr->namespacePtr;
+	if (nsPtr->parentPtr != NULL) {
+	    nsPtr = nsPtr->parentPtr;
+	}
+
     }
     oPtr->command = TclCreateObjCommandInNs(interp, nameStr,
 	(Tcl_Namespace *)nsPtr, PublicObjectCmd, oPtr, NULL);
@@ -672,26 +714,8 @@ AllocObject(
     tracePtr->nextPtr = NULL;
     tracePtr->refCount = 1;
 
-    /*
-     * Access the namespace command table directly when creating "my" to avoid
-     * a bottleneck in string manipulation. Another abstraction-buster.
-     */
-
-    cmdPtr = ckalloc(sizeof(Command));
-    memset(cmdPtr, 0, sizeof(Command));
-    cmdPtr->nsPtr = (Namespace *) oPtr->namespacePtr;
-    cmdPtr->hPtr = Tcl_CreateHashEntry(&cmdPtr->nsPtr->cmdTable, "my",
-	    &ignored);
-    cmdPtr->refCount = 1;
-    cmdPtr->objProc = PrivateObjectCmd;
-    cmdPtr->deleteProc = MyDeleted;
-    cmdPtr->objClientData = cmdPtr->deleteData = oPtr;
-    cmdPtr->proc = TclInvokeObjectCommand;
-    cmdPtr->clientData = cmdPtr;
-    cmdPtr->nreProc = PrivateNRObjectCmd;
-    Tcl_SetHashValue(cmdPtr->hPtr, cmdPtr);
-    oPtr->myCommand = (Tcl_Command) cmdPtr;
-
+    oPtr->myCommand = TclNRCreateCommandInNs(interp, "my", oPtr->namespacePtr,
+	PrivateObjectCmd, PrivateNRObjectCmd, oPtr, MyDeleted);
     return oPtr;
 }
 
@@ -773,88 +797,20 @@ ObjectRenamedTrace(
 
     /*
      * The namespace is only deleted if it hasn't already been deleted. [Bug
-     * 2950259]. If the namespace has already been deleted, then
-     * ObjectNamespaceDeleted() has already cleaned up this command.
+     * 2950259].
      */
 
-    if (oPtr->namespacePtr == NULL) {
-	/*
-	 * ObjectNamespaceDeleted() has already done all the cleanup, but
-	 * detected that the command was in the process of being deleted, and
-	 * left the pointer allocated for us.
-	 */
-	DelRef(oPtr);
-    } else {
-	if (((Namespace *) oPtr->namespacePtr)->earlyDeleteProc == NULL) {
-	    /*
-	     * ObjectNamespaceDeleted() called us, and still has some work to
-	     * do, so we leave the pointer allocated for it to finish, and then
-	     * it will deallocate the pointer.
-	     */
-	} else {
-	    Tcl_DeleteNamespace(oPtr->namespacePtr);
-	    /*
-	     * ObjectNamespaceDeleted() doesn't know it was us that just
-	     * called, so it left the pointer allocated.
-	     */
-	    DelRef(oPtr);
-	}
+    if (!Deleted(oPtr)) {
+	Tcl_DeleteNamespace(oPtr->namespacePtr);
     }
+    oPtr->command = NULL;
+    TclOODecrRefCount(oPtr);
     return;
 }
 
 /*
  * ----------------------------------------------------------------------
  *
- * ClearMixins, ClearSuperclasses --
- *
- *	Utility functions for correctly clearing the list of mixins or
- *	superclasses of a class. Will ckfree() the list storage.
- *
- * ----------------------------------------------------------------------
- */
-
-static void
-ClearMixins(
-    Class *clsPtr)
-{
-    int i;
-    Class *mixinPtr;
-
-    if (clsPtr->mixins.num == 0) {
-	return;
-    }
-
-    FOREACH(mixinPtr, clsPtr->mixins) {
-	TclOORemoveFromMixinSubs(clsPtr, mixinPtr);
-    }
-    ckfree(clsPtr->mixins.list);
-    clsPtr->mixins.list = NULL;
-    clsPtr->mixins.num = 0;
-}
-
-static void
-ClearSuperclasses(
-    Class *clsPtr)
-{
-    int i;
-    Class *superPtr;
-
-    if (clsPtr->superclasses.num == 0) {
-	return;
-    }
-
-    FOREACH(superPtr, clsPtr->superclasses) {
-	TclOORemoveFromSubclasses(clsPtr, superPtr);
-    }
-    ckfree(clsPtr->superclasses.list);
-    clsPtr->superclasses.list = NULL;
-    clsPtr->superclasses.num = 0;
-}
-
-/*
- * ----------------------------------------------------------------------
- *
  * ReleaseClassContents --
  *
  *	Tear down the special class data structure, including deleting all
@@ -864,122 +820,39 @@ ClearSuperclasses(
  */
 
 static void
-ReleaseClassContents(
+DeleteDescendants(
     Tcl_Interp *interp,		/* The interpreter containing the class. */
     Object *oPtr)		/* The object representing the class. */
 {
-    FOREACH_HASH_DECLS;
-    int i;
-    Class *clsPtr = oPtr->classPtr, *mixinSubclassPtr, *subclassPtr;
+    Class *clsPtr = oPtr->classPtr, *subclassPtr, *mixinSubclassPtr;
     Object *instancePtr;
-    Method *mPtr;
-    Foundation *fPtr = oPtr->fPtr;
-    Tcl_Obj *variableObj;
-
-    /*
-     * Sanity check!
-     */
-
-    if (!Deleted(oPtr)) {
-	if (IsRootClass(oPtr)) {
-	    Tcl_Panic("deleting class structure for non-deleted %s",
-		    "::oo::class");
-	} else if (IsRootObject(oPtr)) {
-	    Tcl_Panic("deleting class structure for non-deleted %s",
-		    "::oo::object");
-	} else {
-	    Tcl_Panic("deleting class structure for non-deleted %s",
-		    "general object");
-	}
-    }
-
-    /*
-     * Lock a number of dependent objects until we've stopped putting our
-     * fingers in them.
-     */
-
-    FOREACH(mixinSubclassPtr, clsPtr->mixinSubs) {
-	if (mixinSubclassPtr != NULL) {
-	    AddRef(mixinSubclassPtr);
-	    AddRef(mixinSubclassPtr->thisPtr);
-	}
-    }
-    FOREACH(subclassPtr, clsPtr->subclasses) {
-	if (subclassPtr != NULL && !IsRoot(subclassPtr)) {
-	    AddRef(subclassPtr);
-	    AddRef(subclassPtr->thisPtr);
-	}
-    }
-    if (!IsRootClass(oPtr)) {
-	FOREACH(instancePtr, clsPtr->instances) {
-	    if (instancePtr != oPtr) {
-		int j;
-		if (instancePtr->selfCls == clsPtr) {
-		    instancePtr->flags |= CLASS_GONE;
-		}
-		for(j=0 ; j<instancePtr->mixins.num ; j++) {
-		    Class *mixin = instancePtr->mixins.list[j];
-		    Class *nextMixin = NULL;
-		    if (mixin == clsPtr) {
-			if (j < instancePtr->mixins.num - 1) {
-			    nextMixin = instancePtr->mixins.list[j+1];
-			}
-			if (j == 0) {
-			    instancePtr->mixins.num = 0;
-			    instancePtr->mixins.list = NULL;
-			} else {
-			    instancePtr->mixins.list[j-1] = nextMixin;
-			}
-			instancePtr->mixins.num -= 1;
-		    }
-		}
-		if (instancePtr != NULL && !IsRoot(instancePtr)) {
-		    AddRef(instancePtr);
-		}
-	    }
-	}
-    }
+    int i;
 
     /*
      * Squelch classes that this class has been mixed into.
      */
 
     FOREACH(mixinSubclassPtr, clsPtr->mixinSubs) {
-	if (mixinSubclassPtr != clsPtr) {
-	    if (!Deleted(mixinSubclassPtr->thisPtr)) {
-		Tcl_DeleteCommandFromToken(interp,
-			mixinSubclassPtr->thisPtr->command);
-	    }
-	    ClearMixins(mixinSubclassPtr);
-	    DelRef(mixinSubclassPtr->thisPtr);
-	    DelRef(mixinSubclassPtr);
+	/* This condition also covers the case where mixinSubclassPtr ==
+	 * clsPtr
+	 */
+	if (!Deleted(mixinSubclassPtr->thisPtr)) {
+	    Tcl_DeleteCommandFromToken(interp,
+		    mixinSubclassPtr->thisPtr->command);
 	}
+	i -= TclOORemoveFromMixinSubs(mixinSubclassPtr, clsPtr);
+	TclOODecrRefCount(mixinSubclassPtr->thisPtr);
     }
-    if (clsPtr->mixinSubs.list != NULL) {
-	ckfree(clsPtr->mixinSubs.list);
-	clsPtr->mixinSubs.list = NULL;
-	clsPtr->mixinSubs.num = 0;
-    }
-
     /*
      * Squelch subclasses of this class.
      */
 
     FOREACH(subclassPtr, clsPtr->subclasses) {
-	if (IsRoot(subclassPtr)) {
-	    continue;
-	}
-	if (!Deleted(subclassPtr->thisPtr)) {
+	if (!Deleted(subclassPtr->thisPtr) && !IsRoot(subclassPtr)) {
 	    Tcl_DeleteCommandFromToken(interp, subclassPtr->thisPtr->command);
 	}
-	ClearSuperclasses(subclassPtr);
-	DelRef(subclassPtr->thisPtr);
-	DelRef(subclassPtr);
-    }
-    if (clsPtr->subclasses.list != NULL) {
-	ckfree(clsPtr->subclasses.list);
-	clsPtr->subclasses.list = NULL;
-	clsPtr->subclasses.num = 0;
+	i -= TclOORemoveFromSubclasses(subclassPtr, clsPtr);
+	TclOODecrRefCount(subclassPtr->thisPtr);
     }
 
     /*
@@ -988,35 +861,43 @@ ReleaseClassContents(
 
     if (!IsRootClass(oPtr)) {
 	FOREACH(instancePtr, clsPtr->instances) {
-	    if (instancePtr != oPtr) {
-		if (instancePtr == NULL || IsRoot(instancePtr)) {
-		    continue;
-		}
-		if (!Deleted(instancePtr)) {
-		    Tcl_DeleteCommandFromToken(interp, instancePtr->command);
-		    /*
-		     * Tcl_DeleteCommandFromToken() may have done to whole
-		     * job for us.  Roll back and check again.
-		     */
-		    i--;
-		    continue;
-		}
-		DelRef(instancePtr);
+	    /* This condition also covers the case where instancePtr == oPtr */
+	    if (!Deleted(instancePtr) && !IsRoot(instancePtr)) {
+		Tcl_DeleteCommandFromToken(interp, instancePtr->command);
 	    }
+	    i -= TclOORemoveFromInstances(instancePtr, clsPtr);
 	}
     }
-    if (clsPtr->instances.list != NULL) {
-	ckfree(clsPtr->instances.list);
-	clsPtr->instances.list = NULL;
-	clsPtr->instances.num = 0;
-    }
+}
+	
+
+static void
+ReleaseClassContents(
+    Tcl_Interp *interp,		/* The interpreter containing the class. */
+    Object *oPtr)		/* The object representing the class. */
+{
+    FOREACH_HASH_DECLS;
+    int i; 
+    Class *clsPtr = oPtr->classPtr, *tmpClsPtr;
+    Method *mPtr;
+    Foundation *fPtr = oPtr->fPtr;
+    Tcl_Obj *variableObj;
 
     /*
-     * Special: We delete these after everything else.
+     * Sanity check!
      */
 
-    if (IsRootClass(oPtr) && !Deleted(fPtr->objectCls->thisPtr)) {
-	Tcl_DeleteCommandFromToken(interp, fPtr->objectCls->thisPtr->command);
+    if (!Deleted(oPtr)) {
+	if (IsRootClass(oPtr)) {
+	    Tcl_Panic("deleting class structure for non-deleted %s",
+		    "::oo::class");
+	} else if (IsRootObject(oPtr)) {
+	    Tcl_Panic("deleting class structure for non-deleted %s",
+		    "::oo::object");
+	} else {
+	    Tcl_Panic("deleting class structure for non-deleted %s",
+		    "general object");
+	}
     }
 
     /*
@@ -1072,8 +953,12 @@ ReleaseClassContents(
 	clsPtr->metadataPtr = NULL;
     }
 
-    ClearMixins(clsPtr);
-    ClearSuperclasses(clsPtr);
+    FOREACH(tmpClsPtr, clsPtr->mixins) {
+	TclOORemoveFromMixinSubs(clsPtr, tmpClsPtr);
+    }
+    FOREACH(tmpClsPtr, clsPtr->superclasses) {
+	TclOORemoveFromSubclasses(clsPtr, tmpClsPtr);
+    }
 
     FOREACH_HASH_VALUE(mPtr, &clsPtr->classMethods) {
 	TclOODelMethodRef(mPtr);
@@ -1089,12 +974,9 @@ ReleaseClassContents(
 	ckfree(clsPtr->variables.list);
     }
 
-    /* Tell oPtr that it's class is gone so that it doesn't try to remove
-     * itself from it's classe's list of instances 
-     */ 
-    oPtr->flags |= CLASS_GONE;
-    DelRef(clsPtr);
-
+    if (IsRootClass(oPtr) && !Deleted(fPtr->objectCls->thisPtr)) {
+	Tcl_DeleteCommandFromToken(interp, fPtr->objectCls->thisPtr->command);
+    }
 }
 
 /*
@@ -1122,13 +1004,26 @@ ObjectNamespaceDeleted(
     Method *mPtr;
     Tcl_Obj *filterObj, *variableObj;
     Tcl_Interp *interp = oPtr->fPtr->interp;
-    int finished = 0, i;
+    int i;
 
+    if (Deleted(oPtr)) {
+	/* To do:  Can ObjectNamespaceDeleted ever be called twice?  If not,
+	 * this guard could be removed.
+	 */
+	return;
+    }
 
-    AddRef(fPtr->classCls);
-    AddRef(fPtr->objectCls);
-    AddRef(fPtr->classCls->thisPtr);
-    AddRef(fPtr->objectCls->thisPtr);
+    /*
+     * One rule for the teardown routines is that if an object is in the
+     * process of being deleted, nothing else may modify its bookeeping
+     * records.  This is the flag that
+     */
+    oPtr->flags |= OBJECT_DELETED;
+
+    /* Let the dominoes fall */
+    if (oPtr->classPtr) {
+	DeleteDescendants(interp, oPtr);
+    }
 
     /*
      * We do not run destructors on the core class objects when the
@@ -1136,15 +1031,14 @@ ObjectNamespaceDeleted(
      * in that case when the destructor is partially deleted before the uses
      * of it have gone. [Bug 2949397]
      */
-
-    if (!(oPtr->flags & DESTRUCTOR_CALLED) && !Tcl_InterpDeleted(interp)) {
+    if (!Tcl_InterpDeleted(interp) && !(oPtr->flags & DESTRUCTOR_CALLED)) {
 	CallContext *contextPtr =
 		TclOOGetCallContext(oPtr, NULL, DESTRUCTOR, NULL);
 	int result;
 
 	Tcl_InterpState state;
-
 	oPtr->flags |= DESTRUCTOR_CALLED;
+
 	if (contextPtr != NULL) {
 	    contextPtr->callPtr->flags |= DESTRUCTOR;
 	    contextPtr->skip = 0;
@@ -1166,7 +1060,7 @@ ObjectNamespaceDeleted(
      * points into freed memory.
      */
 
-    if ((((Command *)oPtr->command)->flags && CMD_IS_DELETED)) {
+    if (((Command *)oPtr->command)->flags && CMD_IS_DELETED) {
 	/*
 	 * Something has already started the command deletion process. We can
 	 * go ahead and clean up the the namespace,
@@ -1177,9 +1071,7 @@ ObjectNamespaceDeleted(
 	 * as well.
 	 */
 	Tcl_DeleteCommandFromToken(oPtr->fPtr->interp, oPtr->command);
-	finished = 1;
     }
-    oPtr->command = NULL;
 
     if (oPtr->myCommand) {
 	Tcl_DeleteCommandFromToken(oPtr->fPtr->interp, oPtr->myCommand);
@@ -1190,14 +1082,11 @@ ObjectNamespaceDeleted(
      * methods on the object.
      */
 
-    if (!IsRootObject(oPtr) && !(oPtr->flags & CLASS_GONE)) {
-	TclOORemoveFromInstances(oPtr, oPtr->selfCls);
-    }
+    /* To do: Should this be protected with a * !IsRoot() condition?  */ 
+    TclOORemoveFromInstances(oPtr, oPtr->selfCls);
 
     FOREACH(mixinPtr, oPtr->mixins) {
-	if (mixinPtr && mixinPtr != oPtr->classPtr) {
-	    TclOORemoveFromInstances(oPtr, mixinPtr);
-	}
+	i -= TclOORemoveFromInstances(oPtr, mixinPtr);
     }
     if (i) {
 	ckfree(oPtr->mixins.list);
@@ -1257,8 +1146,9 @@ ObjectNamespaceDeleted(
      * classes, if one goes the other must too and yet the tangle can
      * sometimes not go away automatically; we force it here. [Bug 2962664]
      */
-    if (!Tcl_InterpDeleted(interp) && IsRootObject(oPtr)
-	    && !Deleted(fPtr->classCls->thisPtr)) {
+    if (IsRootObject(oPtr) && !Deleted(fPtr->classCls->thisPtr)
+	&& !Tcl_InterpDeleted(interp)) {
+
 	Tcl_DeleteCommandFromToken(interp, fPtr->classCls->thisPtr->command);
     }
 
@@ -1266,35 +1156,59 @@ ObjectNamespaceDeleted(
 	ReleaseClassContents(interp, oPtr);
     }
 
-
     /*
      * Delete the object structure itself.
      */
 
-    oPtr->classPtr = NULL;
     oPtr->namespacePtr = NULL;
-
-    DelRef(fPtr->classCls->thisPtr);
-    DelRef(fPtr->objectCls->thisPtr);
-    DelRef(fPtr->classCls);
-    DelRef(fPtr->objectCls);
-    if (finished) {
-	/*
-	 * ObjectRenamedTrace called us, and not the other way around.
-	 */
-	DelRef(oPtr);
-    } else {
-	/*
-	 * ObjectRenamedTrace will call DelRef(oPtr).
-	 */
-    }
+    oPtr->selfCls = NULL;
+    TclOODecrRefCount(oPtr);
     return;
-
 }
 
 /*
  * ----------------------------------------------------------------------
  *
+ * TclOODecrRef --
+ *
+ *	Decrement the refcount of an object and deallocate storage then object
+ *	is no longer referenced.  Returns 1 if storage was deallocated, and 0
+ *	otherwise.
+ *
+ * ----------------------------------------------------------------------
+ */
+int TclOODecrRefCount(Object *oPtr) {
+    if (oPtr->refCount-- <= 1) {
+	Class *clsPtr = oPtr->classPtr;
+	if (oPtr->classPtr != NULL) {
+	    ckfree(clsPtr->superclasses.list);
+	    ckfree(clsPtr->subclasses.list);
+	    ckfree(clsPtr->instances.list);
+	    ckfree(clsPtr->mixinSubs.list);
+	    ckfree(clsPtr->mixins.list);
+	    ckfree(oPtr->classPtr);
+	}
+	ckfree(oPtr);
+	return 1;
+    }
+    return 0;
+}
+
+/* setting the "empty" location to NULL makes debugging a little easier */
+#define REMOVEBODY { \
+    for (; idx < num - 1; idx++) { \
+	list[idx] = list[idx+1]; \
+    } \
+    list[idx] = NULL;  \
+    return; \
+}
+void RemoveClass(Class **list, int num, int idx) REMOVEBODY
+
+void RemoveObject(Object **list, int num, int idx) REMOVEBODY
+
+/*
+ * ----------------------------------------------------------------------
+ *
  * TclOORemoveFromInstances --
  *
  *	Utility function to remove an object from the list of instances within
@@ -1303,36 +1217,27 @@ ObjectNamespaceDeleted(
  * ----------------------------------------------------------------------
  */
 
-void
+int
 TclOORemoveFromInstances(
     Object *oPtr,		/* The instance to remove. */
     Class *clsPtr)		/* The class (possibly) containing the
 				 * reference to the instance. */
 {
-    int i;
+    int i, res = 0;
     Object *instPtr;
+    if (Deleted(clsPtr->thisPtr)) {
+	return res;
+    }
 
     FOREACH(instPtr, clsPtr->instances) {
 	if (oPtr == instPtr) {
-	    goto removeInstance;
-	}
-    }
-    return;
-
-  removeInstance:
-    if (Deleted(clsPtr->thisPtr)) {
-	if (!IsRootClass(clsPtr)) {
-	    DelRef(clsPtr->instances.list[i]);
-	}
-	clsPtr->instances.list[i] = NULL;
-    } else {
-	clsPtr->instances.num--;
-	if (i < clsPtr->instances.num) {
-	    clsPtr->instances.list[i] =
-		    clsPtr->instances.list[clsPtr->instances.num];
+	    RemoveItem(Object, clsPtr->instances, i);
+	    TclOODecrRefCount(oPtr);
+	    res++;
+	    break;
 	}
-	clsPtr->instances.list[clsPtr->instances.num] = NULL;
     }
+    return res;
 }
 
 /*
@@ -1353,9 +1258,6 @@ TclOOAddToInstances(
 				 * assumed that the class is not already
 				 * present as an instance in the class. */
 {
-    if (Deleted(clsPtr->thisPtr)) {
-	return;
-    }
     if (clsPtr->instances.num >= clsPtr->instances.size) {
 	clsPtr->instances.size += ALLOC_CHUNK;
 	if (clsPtr->instances.size == ALLOC_CHUNK) {
@@ -1366,6 +1268,7 @@ TclOOAddToInstances(
 	}
     }
     clsPtr->instances.list[clsPtr->instances.num++] = oPtr;
+    AddRef(oPtr);
 }
 
 /*
@@ -1374,36 +1277,31 @@ TclOOAddToInstances(
  * TclOORemoveFromSubclasses --
  *
  *	Utility function to remove a class from the list of subclasses within
- *	another class.
+ *	another class. Returns the number of removals performed.
  *
  * ----------------------------------------------------------------------
  */
 
-void
+int
 TclOORemoveFromSubclasses(
     Class *subPtr,		/* The subclass to remove. */
     Class *superPtr)		/* The superclass to possibly remove the
 				 * subclass reference from. */
 {
-    int i;
+    int i, res = 0;
     Class *subclsPtr;
+    if (Deleted(superPtr->thisPtr)) {
+	return res;
+    }
 
     FOREACH(subclsPtr, superPtr->subclasses) {
 	if (subPtr == subclsPtr) {
-	    goto removeSubclass;
-	}
-    }
-    return;
-
-  removeSubclass:
-    if (!Deleted(superPtr->thisPtr)) {
-	superPtr->subclasses.num--;
-	if (i < superPtr->subclasses.num) {
-	    superPtr->subclasses.list[i] =
-		    superPtr->subclasses.list[superPtr->subclasses.num];
+	    RemoveItem(Class, superPtr->subclasses, i);
+	    TclOODecrRefCount(subPtr->thisPtr);
+	    res++;
 	}
-	superPtr->subclasses.list[superPtr->subclasses.num] = NULL;
     }
+    return res;
 }
 
 /*
@@ -1430,13 +1328,13 @@ TclOOAddToSubclasses(
     if (superPtr->subclasses.num >= superPtr->subclasses.size) {
 	superPtr->subclasses.size += ALLOC_CHUNK;
 	if (superPtr->subclasses.size == ALLOC_CHUNK) {
-	    superPtr->subclasses.list = ckalloc(sizeof(Class*) * ALLOC_CHUNK);
+	    superPtr->subclasses.list = ckalloc(sizeof(Class *) * ALLOC_CHUNK);
 	} else {
-	    superPtr->subclasses.list = ckrealloc(superPtr->subclasses.list,
-		    sizeof(Class *) * superPtr->subclasses.size);
+	    superPtr->subclasses.list = ckrealloc(superPtr->subclasses.list, sizeof(Class *) * superPtr->subclasses.size);
 	}
     }
     superPtr->subclasses.list[superPtr->subclasses.num++] = subPtr;
+    AddRef(subPtr->thisPtr);
 }
 
 /*
@@ -1450,31 +1348,28 @@ TclOOAddToSubclasses(
  * ----------------------------------------------------------------------
  */
 
-void
+int
 TclOORemoveFromMixinSubs(
     Class *subPtr,		/* The subclass to remove. */
     Class *superPtr)		/* The superclass to possibly remove the
 				 * subclass reference from. */
 {
-    int i;
+    int i, res = 0;
     Class *subclsPtr;
 
-    FOREACH(subclsPtr, superPtr->mixinSubs) {
-	if (subPtr == subclsPtr) {
-	    goto removeSubclass;
-	}
+    if (Deleted(superPtr->thisPtr)) {
+	return res;
     }
-    return;
 
-  removeSubclass:
-    if (!Deleted(superPtr->thisPtr)) {
-	superPtr->mixinSubs.num--;
-	if (i < superPtr->mixinSubs.num) {
-	    superPtr->mixinSubs.list[i] =
-		    superPtr->mixinSubs.list[superPtr->mixinSubs.num];
+    FOREACH(subclsPtr, superPtr->mixinSubs) {
+	if (subPtr == subclsPtr) {
+	    RemoveItem(Class, superPtr->mixinSubs, i);
+	    TclOODecrRefCount(subPtr->thisPtr);
+	    res++;
+	    break;
 	}
-	superPtr->mixinSubs.list[superPtr->mixinSubs.num] = NULL;
     }
+    return res;
 }
 
 /*
@@ -1508,6 +1403,7 @@ TclOOAddToMixinSubs(
 	}
     }
     superPtr->mixinSubs.list[superPtr->mixinSubs.num++] = subPtr;
+    AddRef(subPtr->thisPtr);
 }
 
 /*
@@ -1515,7 +1411,7 @@ TclOOAddToMixinSubs(
  *
  * AllocClass --
  *
- *	Allocate a basic class. Does not splice the class object into its
+ *	Allocate a basic class. Does not add class to its
  *	class's instance list.
  *
  * ----------------------------------------------------------------------
@@ -1526,44 +1422,18 @@ AllocClass(
     Tcl_Interp *interp,		/* Interpreter within which to allocate the
 				 * class. */
     Object *useThisObj)		/* Object that is to act as the class
-				 * representation, or NULL if a new object
-				 * with automatic name is to be used. */
+				 * representation. */
 {
     Foundation *fPtr = GetFoundation(interp);
     Class *clsPtr = ckalloc(sizeof(Class));
 
-    /*
-     * Make an object if we haven't been given one.
-     */
-
     memset(clsPtr, 0, sizeof(Class));
-    if (useThisObj == NULL) {
-	clsPtr->thisPtr = AllocObject(interp, NULL, NULL, NULL);
-    } else {
-	clsPtr->thisPtr = useThisObj;
-    }
+    clsPtr->thisPtr = useThisObj;
 
     /*
      * Configure the namespace path for the class's object.
      */
-
-    if (fPtr->helpersNs != NULL) {
-	Tcl_Namespace *path[2];
-
-	path[0] = fPtr->helpersNs;
-	path[1] = fPtr->ooNs;
-	TclSetNsPath((Namespace *) clsPtr->thisPtr->namespacePtr, 2, path);
-    } else {
-	TclSetNsPath((Namespace *) clsPtr->thisPtr->namespacePtr, 1,
-		&fPtr->ooNs);
-    }
-
-    /*
-     * Class objects inherit from the class of classes unless they inherit
-     * from some subclass of it. Enforce this right now.
-     */
-
-    clsPtr->thisPtr->selfCls = fPtr->classCls;
+    initClassPath(interp, clsPtr);
 
     /*
      * Classes are subclasses of oo::object, i.e. the objects they create are
@@ -1573,6 +1443,7 @@ AllocClass(
     clsPtr->superclasses.num = 1;
     clsPtr->superclasses.list = ckalloc(sizeof(Class *));
     clsPtr->superclasses.list[0] = fPtr->objectCls;
+    AddRef(fPtr->objectCls->thisPtr);
 
     /*
      * Finish connecting the class structure to the object structure.
@@ -1585,10 +1456,22 @@ AllocClass(
      * fields.
      */
 
-    clsPtr->refCount = 1;
     Tcl_InitObjHashTable(&clsPtr->classMethods);
     return clsPtr;
 }
+static void
+initClassPath(Tcl_Interp *interp, Class *clsPtr) {
+    Foundation *fPtr = GetFoundation(interp);
+    if (fPtr->helpersNs != NULL) {
+	Tcl_Namespace *path[2];
+	path[0] = fPtr->helpersNs;
+	path[1] = fPtr->ooNs;
+	TclSetNsPath((Namespace *) clsPtr->thisPtr->namespacePtr, 2, path);
+    } else {
+	TclSetNsPath((Namespace *) clsPtr->thisPtr->namespacePtr, 1,
+		&fPtr->ooNs);
+    }
+}
 
 /*
  * ----------------------------------------------------------------------
@@ -1639,7 +1522,7 @@ Tcl_NewObjectInstance(
 	    contextPtr->skip = skip;
 
 	    /*
-	     * Adjust the ensmble tracking record if necessary. [Bug 3514761]
+	     * Adjust the ensemble tracking record if necessary. [Bug 3514761]
 	     */
 
 	    isRoot = TclInitRewriteEnsemble(interp, skip, skip, objv);
@@ -1655,7 +1538,6 @@ Tcl_NewObjectInstance(
 	    clientData[2] = state;
 	    clientData[3] = &oPtr;
 
-	    AddRef(oPtr);
 	    result = FinalizeAlloc(clientData, interp, result);
 	    if (result != TCL_OK) {
 		return NULL;
@@ -1722,7 +1604,6 @@ TclNRNewObjectInstance(
      * Fire off the constructors non-recursively.
      */
 
-    AddRef(oPtr);
     TclNRAddCallback(interp, FinalizeAlloc, contextPtr, oPtr, state,
 	    objectPtr);
     TclPushTailcallPoint(interp);
@@ -1770,18 +1651,9 @@ TclNewObjectInstanceCommon(
      * Create the object.
      */
 
-    /*
-     * The command for the object could have the same name as the command
-     * associated with classPtr, so protect the structure from deallocation
-     * here.
-     */
-    AddRef(classPtr);
-
     oPtr = AllocObject(interp, simpleName, nsPtr, nsNameStr);
-    DelRef(classPtr);
     oPtr->selfCls = classPtr;
     TclOOAddToInstances(oPtr, classPtr);
-
     /*
      * Check to see if we're really creating a class. If so, allocate the
      * class structure as well.
@@ -1796,7 +1668,6 @@ TclNewObjectInstanceCommon(
 	 */
 
 	AllocClass(interp, oPtr);
-	oPtr->selfCls = classPtr;
 	TclOOAddToSubclasses(oPtr->classPtr, fPtr->objectCls);
     } else {
 	oPtr->classPtr = NULL;
@@ -1828,7 +1699,6 @@ FinalizeAlloc(
 	Tcl_SetErrorCode(interp, "TCL", "OO", "STILLBORN", NULL);
 	result = TCL_ERROR;
     }
-    TclOODeleteContext(contextPtr);
     if (result != TCL_OK) {
 	Tcl_DiscardInterpState(state);
 
@@ -1842,12 +1712,14 @@ FinalizeAlloc(
 	    (void) TclOOObjectName(interp, oPtr);
 	    Tcl_DeleteCommandFromToken(interp, oPtr->command);
 	}
-	DelRef(oPtr);
+	/* This decrements the refcount of oPtr */
+	TclOODeleteContext(contextPtr);
 	return TCL_ERROR;
     }
     Tcl_RestoreInterpState(interp, state);
     *objectPtr = (Tcl_Object) oPtr;
-    DelRef(oPtr);
+    /* This decrements the refcount of oPtr */
+    TclOODeleteContext(contextPtr);
     return TCL_OK;
 }
 
@@ -1955,8 +1827,7 @@ Tcl_CopyObjectInstance(
      */
 
     o2Ptr->flags = oPtr->flags & ~(
-	    OBJECT_DELETED | ROOT_OBJECT | ROOT_CLASS | FILTER_HANDLING);
-
+	    OBJECT_DELETED | ROOT_OBJECT | ROOT_CLASS | FILTER_HANDLING); 
     /*
      * Copy the object's metadata.
      */
@@ -2968,7 +2839,7 @@ int
 Tcl_ObjectDeleted(
     Tcl_Object object)
 {
-    return Deleted(object) ? 1 : 0;
+    return ((Object *)object)->command == NULL;
 }
 
 Tcl_Object
diff --git a/generic/tclOOBasic.c b/generic/tclOOBasic.c
index b2c06a7..d874cba 100644
--- a/generic/tclOOBasic.c
+++ b/generic/tclOOBasic.c
@@ -1206,22 +1206,10 @@ TclOOCopyObjectCmd(
 	o2Ptr = Tcl_CopyObjectInstance(interp, oPtr, NULL, NULL);
     } else {
 	const char *name, *namespaceName;
-	Tcl_DString buffer;
 
 	name = TclGetString(objv[2]);
-	Tcl_DStringInit(&buffer);
 	if (name[0] == '\0') {
 	    name = NULL;
-	} else if (name[0]!=':' || name[1]!=':') {
-	    Interp *iPtr = (Interp *) interp;
-
-	    if (iPtr->varFramePtr != NULL) {
-		Tcl_DStringAppend(&buffer,
-			iPtr->varFramePtr->nsPtr->fullName, -1);
-	    }
-	    TclDStringAppendLiteral(&buffer, "::");
-	    Tcl_DStringAppend(&buffer, name, -1);
-	    name = Tcl_DStringValue(&buffer);
 	}
 
 	/*
@@ -1243,7 +1231,6 @@ TclOOCopyObjectCmd(
 	}
 
 	o2Ptr = Tcl_CopyObjectInstance(interp, oPtr, name, namespaceName);
-	Tcl_DStringFree(&buffer);
     }
 
     if (o2Ptr == NULL) {
diff --git a/generic/tclOOCall.c b/generic/tclOOCall.c
index d4e1e34..c71425b 100644
--- a/generic/tclOOCall.c
+++ b/generic/tclOOCall.c
@@ -110,7 +110,8 @@ TclOODeleteContext(
     TclOODeleteChain(contextPtr->callPtr);
     if (oPtr != NULL) {
 	TclStackFree(oPtr->fPtr->interp, contextPtr);
-	DelRef(oPtr);
+	/* Corresponding AddRef() in TclOO.c/TclOOObjectCmdCore */
+	TclOODecrRefCount(oPtr);
     }
 }
 
@@ -1171,6 +1172,7 @@ TclOOGetCallContext(
   returnContext:
     contextPtr = TclStackAlloc(oPtr->fPtr->interp, sizeof(CallContext));
     contextPtr->oPtr = oPtr;
+    /* Corresponding TclOODecrRefCount() in TclOODeleteContext */ 
     AddRef(oPtr);
     contextPtr->callPtr = callPtr;
     contextPtr->skip = 2;
diff --git a/generic/tclOODefineCmds.c b/generic/tclOODefineCmds.c
index 47b34bb..d05d899 100644
--- a/generic/tclOODefineCmds.c
+++ b/generic/tclOODefineCmds.c
@@ -326,9 +326,7 @@ TclOOObjectSetMixins(
     if (numMixins == 0) {
 	if (oPtr->mixins.num != 0) {
 	    FOREACH(mixinPtr, oPtr->mixins) {
-		if (mixinPtr) {
-		    TclOORemoveFromInstances(oPtr, mixinPtr);
-		}
+		TclOORemoveFromInstances(oPtr, mixinPtr);
 	    }
 	    ckfree(oPtr->mixins.list);
 	    oPtr->mixins.num = 0;
@@ -352,6 +350,10 @@ TclOOObjectSetMixins(
 	FOREACH(mixinPtr, oPtr->mixins) {
 	    if (mixinPtr != oPtr->selfCls) {
 		TclOOAddToInstances(oPtr, mixinPtr);
+		/* Corresponding TclOODecrRefCount() is in the caller of this
+		 * function. 
+		 */
+		TclOODecrRefCount(mixinPtr->thisPtr);
 	    }
 	}
     }
@@ -399,6 +401,10 @@ TclOOClassSetMixins(
 	memcpy(classPtr->mixins.list, mixins, sizeof(Class *) * numMixins);
 	FOREACH(mixinPtr, classPtr->mixins) {
 	    TclOOAddToMixinSubs(classPtr, mixinPtr);
+	    /* Corresponding TclOODecrRefCount() is in the caller of this
+	     * function
+	     */
+	    TclOODecrRefCount(mixinPtr->thisPtr);
 	}
     }
     BumpGlobalEpoch(interp, classPtr);
@@ -914,7 +920,7 @@ TclOODefineObjCmd(
     } else {
 	result = MagicDefinitionInvoke(interp, fPtr->defineNs, 2, objc, objv);
     }
-    DelRef(oPtr);
+    TclOODecrRefCount(oPtr);
 
     /*
      * Restore the previous "current" namespace.
@@ -981,7 +987,7 @@ TclOOObjDefObjCmd(
     } else {
 	result = MagicDefinitionInvoke(interp, fPtr->objdefNs, 2, objc, objv);
     }
-    DelRef(oPtr);
+    TclOODecrRefCount(oPtr);
 
     /*
      * Restore the previous "current" namespace.
@@ -1048,7 +1054,7 @@ TclOODefineSelfObjCmd(
     } else {
 	result = MagicDefinitionInvoke(interp, fPtr->objdefNs, 1, objc, objv);
     }
-    DelRef(oPtr);
+    TclOODecrRefCount(oPtr);
 
     /*
      * Restore the previous "current" namespace.
@@ -1120,11 +1126,11 @@ TclOODefineClassObjCmd(
 
     if (oPtr->selfCls != clsPtr) {
 	TclOORemoveFromInstances(oPtr, oPtr->selfCls);
+
+	/* Reference count already incremented 3 lines up. */
 	oPtr->selfCls = clsPtr;
+
 	TclOOAddToInstances(oPtr, oPtr->selfCls);
-	if (!(clsPtr->thisPtr->flags & OBJECT_DELETED)) {
-	    oPtr->flags &= ~CLASS_GONE;
-	}
 	if (oPtr->classPtr != NULL) {
 	    BumpGlobalEpoch(interp, oPtr->classPtr);
 	} else {
@@ -1580,6 +1586,10 @@ TclOODefineMixinObjCmd(
 	    goto freeAndError;
 	}
 	mixins[i-1] = clsPtr;
+	/* Corresponding TclOODecrRefCount() is in TclOOObjectSetMixins,
+	 * TclOOClassSetMixinsk, or just below if this function fails.
+	 */
+	AddRef(mixins[i-1]->thisPtr);
     }
 
     if (isInstanceMixin) {
@@ -1592,6 +1602,9 @@ TclOODefineMixinObjCmd(
     return TCL_OK;
 
   freeAndError:
+    while (--i > 0) {
+	TclOODecrRefCount(mixins[i]->thisPtr);
+    }
     TclStackFree(interp, mixins);
     return TCL_ERROR;
 }
@@ -2007,6 +2020,7 @@ ClassMixinSet(
 	mixins[i] = GetClassInOuterContext(interp, mixinv[i],
 		"may only mix in classes");
 	if (mixins[i] == NULL) {
+	    i--;
 	    goto freeAndError;
 	}
 	if (TclOOIsReachable(oPtr->classPtr, mixins[i])) {
@@ -2015,6 +2029,10 @@ ClassMixinSet(
 	    Tcl_SetErrorCode(interp, "TCL", "OO", "SELF_MIXIN", NULL);
 	    goto freeAndError;
 	}
+	/* Corresponding TclOODecrRefCount() is in TclOOClassSetMixins, or just
+	 * below if this function fails
+	 */
+	AddRef(mixins[i]->thisPtr);
     }
 
     TclOOClassSetMixins(interp, oPtr->classPtr, mixinc, mixins);
@@ -2022,6 +2040,9 @@ ClassMixinSet(
     return TCL_OK;
 
   freeAndError:
+    while (i-- > 0) {
+	TclOODecrRefCount(mixins[i]->thisPtr);
+    }
     TclStackFree(interp, mixins);
     return TCL_ERROR;
 }
@@ -2124,16 +2145,20 @@ ClassSuperSet(
 
     if (superc == 0) {
 	superclasses = ckrealloc(superclasses, sizeof(Class *));
-	superclasses[0] = oPtr->fPtr->objectCls;
-	superc = 1;
 	if (TclOOIsReachable(oPtr->fPtr->classCls, oPtr->classPtr)) {
 	    superclasses[0] = oPtr->fPtr->classCls;
+	} else {
+	    superclasses[0] = oPtr->fPtr->objectCls;
 	}
+	superc = 1;
+	/* Corresponding TclOODecrRefCount is near the end of this function */
+	AddRef(superclasses[0]->thisPtr);
     } else {
 	for (i=0 ; i<superc ; i++) {
 	    superclasses[i] = GetClassInOuterContext(interp, superv[i],
 		    "only a class can be a superclass");
 	    if (superclasses[i] == NULL) {
+		i--;
 		goto failedAfterAlloc;
 	    }
 	    for (j=0 ; j<i ; j++) {
@@ -2150,9 +2175,15 @@ ClassSuperSet(
 			"attempt to form circular dependency graph", -1));
 		Tcl_SetErrorCode(interp, "TCL", "OO", "CIRCULARITY", NULL);
 	    failedAfterAlloc:
-		ckfree((char *) superclasses);
+		for (; i > 0; i--) {
+		    TclOODecrRefCount(superclasses[i]->thisPtr);
+		}
+		ckfree(superclasses);
 		return TCL_ERROR;
 	    }
+	    /* Corresponding TclOODecrRefCount() is near the end of this
+	     * function */
+	    AddRef(superclasses[i]->thisPtr);
 	}
     }
 
@@ -2173,6 +2204,8 @@ ClassSuperSet(
     oPtr->classPtr->superclasses.num = superc;
     FOREACH(superPtr, oPtr->classPtr->superclasses) {
 	TclOOAddToSubclasses(oPtr->classPtr, superPtr);
+	/* To account for the AddRef() earlier in this function */ 
+	TclOODecrRefCount(superPtr->thisPtr);
     }
     BumpGlobalEpoch(interp, oPtr->classPtr);
 
@@ -2463,9 +2496,16 @@ ObjMixinSet(
 	mixins[i] = GetClassInOuterContext(interp, mixinv[i],
 		"may only mix in classes");
 	if (mixins[i] == NULL) {
+	    while (i-- > 0) {
+		TclOODecrRefCount(mixins[i]->thisPtr);
+	    }
 	    TclStackFree(interp, mixins);
 	    return TCL_ERROR;
 	}
+	/* Corresponding TclOODecrRefCount() is in TclOOObjectSetMixins() or
+	 * just above if this function fails.
+	 */
+	AddRef(mixins[i]->thisPtr);
     }
 
     TclOOObjectSetMixins(oPtr, mixinc, mixins);
diff --git a/generic/tclOOInt.h b/generic/tclOOInt.h
index 292293c..61ead01 100644
--- a/generic/tclOOInt.h
+++ b/generic/tclOOInt.h
@@ -193,9 +193,10 @@ typedef struct Object {
 				 * destroyed. */
 #define DESTRUCTOR_CALLED 2	/* Flag to say that the destructor has been
 				 * called. */
-#define CLASS_GONE	4	/* Indicates that the class of this object has
-				 * been deleted, and so the object should not
-				 * attempt to remove itself from its class. */
+#define CLASS_GONE	4	/* Obsolete. Indicates that the class of this
+				 * object has been deleted, and so the object
+				 * should not attempt to remove itself from its
+				 * class. */
 #define ROOT_OBJECT 0x1000	/* Flag to say that this object is the root of
 				 * the class hierarchy and should be treated
 				 * specially during teardown. */
@@ -222,10 +223,6 @@ typedef struct Object {
 typedef struct Class {
     Object *thisPtr;		/* Reference to the object associated with
 				 * this class. */
-    int refCount;		/* Number of strong references to this class.
-				 * Weak references are not counted; the
-				 * purpose of this is to avoid Tcl_Preserve as
-				 * that is quite slow. */
     int flags;			/* Assorted flags. */
     LIST_STATIC(struct Class *) superclasses;
 				/* List of superclasses, used for generation
@@ -496,6 +493,7 @@ MODULE_SCOPE Object *	TclNewObjectInstanceCommon(Tcl_Interp *interp,
 			    Class *classPtr,
 			    const char *nameStr,
 			    const char *nsNameStr);
+MODULE_SCOPE int	TclOODecrRefCount(Object *oPtr);
 MODULE_SCOPE int	TclOODefineSlots(Foundation *fPtr);
 MODULE_SCOPE void	TclOODeleteChain(CallChain *callPtr);
 MODULE_SCOPE void	TclOODeleteChainCache(Tcl_HashTable *tablePtr);
@@ -525,10 +523,10 @@ MODULE_SCOPE int	TclNRObjectContextInvokeNext(Tcl_Interp *interp,
 MODULE_SCOPE void	TclOONewBasicMethod(Tcl_Interp *interp, Class *clsPtr,
 			    const DeclaredClassMethod *dcm);
 MODULE_SCOPE Tcl_Obj *	TclOOObjectName(Tcl_Interp *interp, Object *oPtr);
-MODULE_SCOPE void	TclOORemoveFromInstances(Object *oPtr, Class *clsPtr);
-MODULE_SCOPE void	TclOORemoveFromMixinSubs(Class *subPtr,
+MODULE_SCOPE int	TclOORemoveFromInstances(Object *oPtr, Class *clsPtr);
+MODULE_SCOPE int	TclOORemoveFromMixinSubs(Class *subPtr,
 			    Class *mixinPtr);
-MODULE_SCOPE void	TclOORemoveFromSubclasses(Class *subPtr,
+MODULE_SCOPE int	TclOORemoveFromSubclasses(Class *subPtr,
 			    Class *superPtr);
 MODULE_SCOPE Tcl_Obj *	TclOORenderCallChain(Tcl_Interp *interp,
 			    CallChain *callPtr);
@@ -543,18 +541,21 @@ MODULE_SCOPE void	TclOOSetupVariableResolver(Tcl_Namespace *nsPtr);
 #include "tclOOIntDecls.h"
 
 /*
+ * Alternatives to Tcl_Preserve/Tcl_EventuallyFree/Tcl_Release.
+ */
+
+#define AddRef(ptr) ((ptr)->refCount++)
+
+/*
  * A convenience macro for iterating through the lists used in the internal
- * memory management of objects. This is a bit gnarly because we want to do
- * the assignment of the picked-out value only when the body test succeeds,
- * but we cannot rely on the assigned value being useful, forcing us to do
- * some nasty stuff with the comma operator. The compiler's optimizer should
- * be able to sort it all out!
- *
+ * memory management of objects.
  * REQUIRES DECLARATION: int i;
  */
 
 #define FOREACH(var,ary) \
-	for(i=0 ; (i<(ary).num?((var=(ary).list[i]),1):0) ; i++)
+    for(i=0 ; i<(ary).num; i++) if ((ary).list[i] == NULL) { \
+	continue; \
+    } else if (var = (ary).list[i], 1) 
 
 /*
  * Convenience macros for iterating through hash tables. FOREACH_HASH_DECLS
@@ -589,17 +590,6 @@ MODULE_SCOPE void	TclOOSetupVariableResolver(Tcl_Namespace *nsPtr);
 	} \
     } while(0)
 
-/*
- * Alternatives to Tcl_Preserve/Tcl_EventuallyFree/Tcl_Release.
- */
-
-#define AddRef(ptr) ((ptr)->refCount++)
-#define DelRef(ptr) do {			\
-	if ((ptr)->refCount-- <= 1) {		\
-	    ckfree((char *) (ptr));		\
-	}					\
-    } while(0)
-
 #endif /* TCL_OO_INTERNAL_H */
 
 /*
diff --git a/tests/oo.test b/tests/oo.test
index 46f8880..9cf3133 100644
--- a/tests/oo.test
+++ b/tests/oo.test
@@ -47,7 +47,7 @@ test oo-0.2 {basic test of OO's ability to clean up its initial state} {
 } {}
 test oo-0.3 {basic test of OO's ability to clean up its initial state} -body {
     leaktest {
-	[oo::object new] destroy
+        [oo::object new] destroy
     }
 } -constraints memory -result 0
 test oo-0.4 {basic test of OO's ability to clean up its initial state} -body {
@@ -131,6 +131,10 @@ test oo-1.4 {basic test of OO functionality} -body {
 test oo-1.4.1 {fully-qualified nested name} -body {
     oo::object create ::one::two::three 
 } -result {::one::two::three}
+test oo-1.4.2 {automatic command name has same name as namespace} -body {
+    set obj [oo::object new]
+    expr {[info object namespace $obj] == $obj}
+} -result 1
 test oo-1.5 {basic test of OO functionality} -body {
     oo::object doesnotexist
 } -returnCodes 1 -result {unknown method "doesnotexist": must be create, destroy or new}
@@ -1514,9 +1518,9 @@ test oo-11.6 {
 
     # No segmentation fault
     return done
-} -cleanup {
+} -result done -cleanup {
     rename obj1 {}
-} -result done
+}
 
 test oo-12.1 {OO: filters} {
     oo::class create Aclass