From fc743498e7623e7cefbe124ef936d30de91e3625 Mon Sep 17 00:00:00 2001
From: dgp <dgp@users.sourceforge.net>
Date: Wed, 7 Sep 2016 18:31:58 +0000
Subject: Attempt to fix [7f02ff1efa]. Make trace-18.1 fail. Suspect test is an
 experiment that preserves the bug.

---
 generic/tclNamesp.c | 20 +++++++-------------
 generic/tclVar.c    | 49 +++++++++++++++++++++++++++++++++----------------
 2 files changed, 40 insertions(+), 29 deletions(-)

diff --git a/generic/tclNamesp.c b/generic/tclNamesp.c
index 7f6ecf5..74dfaf8 100644
--- a/generic/tclNamesp.c
+++ b/generic/tclNamesp.c
@@ -382,19 +382,6 @@ Tcl_PopCallFrame(
     register CallFrame *framePtr = iPtr->framePtr;
     Namespace *nsPtr;
 
-    /*
-     * It's important to remove the call frame from the interpreter's stack of
-     * call frames before deleting local variables, so that traces invoked by
-     * the variable deletion don't see the partially-deleted frame.
-     */
-
-    if (framePtr->callerPtr) {
-	iPtr->framePtr = framePtr->callerPtr;
-	iPtr->varFramePtr = framePtr->callerVarPtr;
-    } else {
-	/* Tcl_PopCallFrame: trying to pop rootCallFrame! */
-    }
-
     if (framePtr->varTablePtr != NULL) {
 	TclDeleteVars(iPtr, framePtr->varTablePtr);
 	ckfree(framePtr->varTablePtr);
@@ -422,6 +409,13 @@ Tcl_PopCallFrame(
     }
     framePtr->nsPtr = NULL;
 
+    if (framePtr->callerPtr) {
+	iPtr->framePtr = framePtr->callerPtr;
+	iPtr->varFramePtr = framePtr->callerVarPtr;
+    } else {
+	/* Tcl_PopCallFrame: trying to pop rootCallFrame! */
+    }
+
     if (framePtr->tailcallPtr) {
 	TclSetTailcall(interp, framePtr->tailcallPtr);
     }
diff --git a/generic/tclVar.c b/generic/tclVar.c
index 48e09f6..0b371ee 100644
--- a/generic/tclVar.c
+++ b/generic/tclVar.c
@@ -5032,27 +5032,44 @@ TclDeleteVars(
     TclVarHashTable *tablePtr)	/* Hash table containing variables to
 				 * delete. */
 {
-    Tcl_Interp *interp = (Tcl_Interp *) iPtr;
     Tcl_HashSearch search;
     register Var *varPtr;
-    int flags;
-    Namespace *currNsPtr = (Namespace *) TclGetCurrentNamespace(interp);
-
-    /*
-     * Determine what flags to pass to the trace callback functions.
-     */
-
-    flags = TCL_TRACE_UNSETS;
-    if (tablePtr == &iPtr->globalNsPtr->varTable) {
-	flags |= TCL_GLOBAL_ONLY;
-    } else if (tablePtr == &currNsPtr->varTable) {
-	flags |= TCL_NAMESPACE_ONLY;
-    }
 
     for (varPtr = VarHashFirstVar(tablePtr, &search); varPtr != NULL;
 	 varPtr = VarHashFirstVar(tablePtr, &search)) {
-	UnsetVarStruct(varPtr, NULL, iPtr, VarHashGetKey(varPtr), NULL, flags,
-		-1);
+	VarHashRefCount(varPtr)++;
+
+	UnsetVarStruct(varPtr, NULL, iPtr, VarHashGetKey(varPtr),
+		NULL, TCL_TRACE_UNSETS, -1);
+
+        if (TclIsVarTraced(varPtr)) {
+            Tcl_HashEntry *tPtr = Tcl_FindHashEntry(&iPtr->varTraces, varPtr);
+            VarTrace *tracePtr = Tcl_GetHashValue(tPtr);
+            ActiveVarTrace *activePtr;
+
+            while (tracePtr) {
+                VarTrace *prevPtr = tracePtr;
+
+                tracePtr = tracePtr->nextPtr;
+                prevPtr->nextPtr = NULL;
+                Tcl_EventuallyFree(prevPtr, TCL_DYNAMIC);
+            }
+            Tcl_DeleteHashEntry(tPtr);
+            varPtr->flags &= ~VAR_ALL_TRACES;
+            for (activePtr = iPtr->activeVarTracePtr; activePtr != NULL;
+                    activePtr = activePtr->nextPtr) {
+                if (activePtr->varPtr == varPtr) {
+                    activePtr->nextTracePtr = NULL;
+                }
+            }
+        }
+
+	if (!TclIsVarUndefined(varPtr)) {
+	    UnsetVarStruct(varPtr, NULL, iPtr, VarHashGetKey(varPtr),
+		    NULL, TCL_TRACE_UNSETS, -1);
+	}
+
+	VarHashRefCount(varPtr)--;
 	VarHashDeleteEntry(varPtr);
     }
     VarHashDeleteTable(tablePtr);
-- 
cgit v0.12