Index: generic/tclCmdMZ.c
===================================================================
RCS file: /cvsroot/tcl/tcl/generic/tclCmdMZ.c,v
retrieving revision 1.26.2.5
diff -b -u -r1.26.2.5 tclCmdMZ.c
--- generic/tclCmdMZ.c	20 Nov 2001 15:14:09 -0000	1.26.2.5
+++ generic/tclCmdMZ.c	29 Mar 2002 22:40:17 -0000
@@ -2654,11 +2654,13 @@
 		while ((clientData = Tcl_VarTraceInfo(interp, name, 0,
 			TraceVarProc, clientData)) != 0) {
 		    tvarPtr = (TraceVarInfo *) clientData;
-		    if ((tvarPtr->length == length) && (tvarPtr->flags == flags)
+		    if ((tvarPtr->length == length)
+			    && (tvarPtr->flags == flags)
 			    && (strncmp(command, tvarPtr->command,
 				    (size_t) length) == 0)) {
 			Tcl_UntraceVar(interp, name, flags | TCL_TRACE_UNSETS,
 				TraceVarProc, clientData);
+
 			if (tvarPtr->errMsg != NULL) {
 			    ckfree(tvarPtr->errMsg);
 			}
@@ -2778,13 +2780,10 @@
 	 * and the terminating null.
 	 */
 
-	if (name2 == NULL) {
-	    name2 = "";
-	}
 	Tcl_DStringInit(&cmd);
 	Tcl_DStringAppend(&cmd, tvarPtr->command, (int) tvarPtr->length);
 	Tcl_DStringAppendElement(&cmd, name1);
-	Tcl_DStringAppendElement(&cmd, name2);
+	Tcl_DStringAppendElement(&cmd, (name2 ? name2 : ""));
 	if (flags & TCL_TRACE_READS) {
 	    Tcl_DStringAppend(&cmd, " r", 2);
 	} else if (flags & TCL_TRACE_WRITES) {
@@ -2796,9 +2795,16 @@
 	/*
 	 * Execute the command.  Save the interp's result used for
 	 * the command. We discard any object result the command returns.
+	 *
+	 * Add the TCL_TRACE_DESTROYED flag to tvarPtr to indicate to
+	 * other areas that this will be destroyed by us, otherwise a
+	 * double-free might occur depending on what the eval does.
 	 */
 
 	Tcl_SaveResult(interp, &state);
+	if (flags & TCL_TRACE_DESTROYED) {
+	    tvarPtr->flags |= TCL_TRACE_DESTROYED;
+	}
 
 	code = Tcl_Eval(interp, Tcl_DStringValue(&cmd));
 	if (code != TCL_OK) {	     /* copy error msg to result */
Index: tests/trace.test
===================================================================
RCS file: /cvsroot/tcl/tcl/tests/trace.test,v
retrieving revision 1.6.2.1
diff -b -u -r1.6.2.1 trace.test
--- tests/trace.test	16 Oct 2001 05:46:04 -0000	1.6.2.1
+++ tests/trace.test	29 Mar 2002 22:40:17 -0000
@@ -977,6 +977,17 @@
     trace variable x r p1
     catch {set x}
 } 1
+test trace-18.2 {namespace delete / trace vdelete combo} {
+    namespace eval ::foo {
+	variable x 123
+    }
+    proc p1 args {
+	trace vdelete ::foo::x u p1
+    }
+    trace variable ::foo::x u p1
+    namespace delete ::foo
+    info exists ::foo::x
+} 0
 
 # Delete arrays when done, so they can be re-used as scalars
 # elsewhere.
@@ -987,15 +998,3 @@
 # cleanup
 ::tcltest::cleanupTests
 return
-
-
-
-
-
-
-
-
-
-
-
-
