Index: generic/tclVar.c
===================================================================
RCS file: /cvsroot/tcl/tcl/generic/tclVar.c,v
retrieving revision 1.133
diff -u -r1.133 tclVar.c
--- generic/tclVar.c	2 May 2007 00:31:22 -0000	1.133
+++ generic/tclVar.c	3 May 2007 22:21:28 -0000
@@ -1097,15 +1097,10 @@
 {
     Var *varPtr, *arrayPtr;
 
-    /*
-     * We need a special flag check to see if we want to create part 1,
-     * because commands like lappend require read traces to trigger for
-     * previously non-existent values.
-     */
-
+    /* Filter to pass through only the flags this interface supports. */
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG);
     varPtr = TclLookupVar(interp, part1, part2, flags, "read",
-	    /*createPart1*/ (flags & TCL_TRACE_READS),
-	    /*createPart2*/ 1, &arrayPtr);
+	    /*createPart1*/ 0, /*createPart2*/ 1, &arrayPtr);
     if (varPtr == NULL) {
 	return NULL;
     }
@@ -1155,15 +1150,10 @@
     part1 = TclGetString(part1Ptr);
     part2 = ((part2Ptr == NULL) ? NULL : TclGetString(part2Ptr));
 
-    /*
-     * We need a special flag check to see if we want to create part 1,
-     * because commands like lappend require read traces to trigger for
-     * previously non-existent values.
-     */
-
+    /* Filter to pass through only the flags this interface supports. */
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG);
     varPtr = TclObjLookupVar(interp, part1Ptr, part2, flags, "read",
-	    /*createPart1*/ (flags & TCL_TRACE_READS),
-	    /*createPart2*/ 1, &arrayPtr);
+	    /*createPart1*/ 0, /*createPart2*/ 1, &arrayPtr);
     if (varPtr == NULL) {
 	return NULL;
     }
@@ -1453,6 +1443,9 @@
 {
     Var *varPtr, *arrayPtr;
 
+    /* Filter to pass through only the flags this interface supports. */
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG
+	    |TCL_APPEND_VALUE|TCL_LIST_ELEMENT);
     varPtr = TclLookupVar(interp, part1, part2, flags, "set",
 	    /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
     if (varPtr == NULL) {
@@ -1512,6 +1505,9 @@
     part1 = TclGetString(part1Ptr);
     part2 = ((part2Ptr == NULL) ? NULL : TclGetString(part2Ptr));
 
+    /* Filter to pass through only the flags this interface supports. */
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG
+	    |TCL_APPEND_VALUE|TCL_LIST_ELEMENT);
     varPtr = TclObjLookupVar(interp, part1Ptr, part2, flags, "set",
 	    /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
     if (varPtr == NULL) {
@@ -1603,7 +1599,8 @@
 
     /*
      * Invoke any read traces that have been set for the variable if it is
-     * requested; this is only done in the core when lappending.
+     * requested; this is only done in the core by the INST_LAPPEND_*
+     * instructions.
      */
 
     if ((flags & TCL_TRACE_READS) && ((varPtr->tracePtr != NULL)
@@ -1936,6 +1933,8 @@
 
     part1Ptr = Tcl_NewStringObj(part1, -1);
     Tcl_IncrRefCount(part1Ptr);
+    /* Filter to pass through only the flags this interface supports. */
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG);
     result = TclObjUnsetVar2(interp, part1Ptr, part2, flags);
     TclDecrRefCount(part1Ptr);
 
@@ -2121,8 +2120,8 @@
     if ((dummyVar.tracePtr != NULL)
 	    || ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) {
 	dummyVar.flags &= ~VAR_TRACE_ACTIVE;
-	TclCallVarTraces(iPtr, arrayPtr, &dummyVar, part1, part2,
-		(flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_INTERP_DESTROYED))
+	TclCallVarTraces(iPtr, arrayPtr, &dummyVar, part1, part2, (flags
+		& (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_INTERP_DESTROYED))
 		| TCL_TRACE_UNSETS, /* leaveErrMsg */ 0);
 	while (dummyVar.tracePtr != NULL) {
 	    VarTrace *tracePtr = dummyVar.tracePtr;
@@ -2146,21 +2145,8 @@
 
     dummyVarPtr = &dummyVar;
     if (TclIsVarArray(dummyVarPtr) && !TclIsVarUndefined(dummyVarPtr)) {
-	/*
-	 * Deleting the elements of the array may cause traces to be fired on
-	 * those elements. Before deleting them, bump the reference count of
-	 * the array, so that if those trace procs make a global or upvar link
-	 * to the array, the array is not deleted when the call stack gets
-	 * popped (we will delete the array ourselves later in this function).
-	 *
-	 * Bumping the count can lead to the odd situation that elements of
-	 * the array are being deleted when the array still exists, but since
-	 * the array is about to be removed anyway, that shouldn't really
-	 * matter.
-	 */
-
-	DeleteArray(iPtr, part1, dummyVarPtr,
-		(flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY))
+	DeleteArray(iPtr, part1, dummyVarPtr, (flags 
+		& (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_INTERP_DESTROYED))
 		| TCL_TRACE_UNSETS);
 
 	/*
@@ -2390,10 +2376,7 @@
 	createdNewObj = 0;
 
 	/*
-	 * Use the TCL_TRACE_READS flag to ensure that if we have an array
-	 * with no elements set yet, but with a read trace on it, we will
-	 * create the variable and get read traces triggered. Note that you
-	 * have to protect the variable pointers around the TclPtrGetVar call
+	 * Protect the variable pointers around the TclPtrGetVar call
 	 * to insure that they remain valid even if the variable was undefined
 	 * and unused.
 	 */
@@ -2409,7 +2392,7 @@
 	}
 	part1 = TclGetString(objv[1]);
 	varValuePtr = TclPtrGetVar(interp, varPtr, arrayPtr, part1, NULL,
-		(TCL_TRACE_READS | TCL_LEAVE_ERR_MSG));
+		TCL_LEAVE_ERR_MSG);
 	varPtr->refCount--;
 	if (arrayPtr != NULL) {
 	    arrayPtr->refCount--;
@@ -4293,6 +4276,9 @@
     int numLocals, i;
 
     flags = TCL_TRACE_UNSETS;
+    if (Tcl_InterpDeleted((Tcl_Interp *)iPtr)) {
+	flags |= TCL_INTERP_DESTROYED;
+    }
     numLocals = framePtr->numCompiledLocals;
     varPtr = framePtr->compiledLocals;
     for (i=0 ; i<numLocals ; i++) {
