* generic/tcl.h: Modified the Tcl call stack so

	* generic/tclBasic.c:      there is always a valid CallFrame, even
	* generic/tclCmdIL.c:      at level 0 [Patch 1577278]. Most of the
	* generic/tclInt.h:        changes involve removing tests for
	* generic/tclNamesp.c:     iPtr->(var)framePtr==NULL. There is now a
	* generic/tclObj.c:        CallFrame pushed at interp creation
	* generic/tclProc.c:       with a pointer to it stored in
	* generic/tclTrace.c:      iPtr->rootFramePtr. A second unused
	* generic/tclVar.c:        field in Interp is hijacked to enable
	further functionality, currently unused (but with several FRQs
	depending on it).

1 files changed, 13 insertions, 15 deletions

diff --git a/generic/tclVar.c b/generic/tclVar.c
index 5f47e7e..4c22bd2 100644
--- a/generic/tclVar.c
+++ b/generic/tclVar.c
@@ -15,7 +15,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclVar.c,v 1.124 2006/10/20 15:16:47 dkf Exp $
+ * RCS: @(#) $Id: tclVar.c,v 1.125 2006/10/23 21:36:55 msofer Exp $
  */
 
 #include "tclInt.h"
@@ -390,7 +390,7 @@ TclObjLookupVar(
     }
     part1 = Tcl_GetStringFromObj(part1Ptr, &len1);
 
-    nsPtr = ((varFramePtr == NULL)? iPtr->globalNsPtr : varFramePtr->nsPtr);
+    nsPtr = varFramePtr->nsPtr;
     if (nsPtr->varResProc != NULL || iPtr->resolverPtr != NULL) {
 	goto doParse;
     }
@@ -398,8 +398,7 @@ TclObjLookupVar(
     if (typePtr == &localVarNameType) {
 	int localIndex = (int) part1Ptr->internalRep.longValue;
 
-	if ((varFramePtr != NULL)
-		&& (varFramePtr->isProcCallFrame & FRAME_IS_PROC)
+	if ((varFramePtr->isProcCallFrame & FRAME_IS_PROC)
 		&& !(flags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY))
 		&& (localIndex < varFramePtr->numCompiledLocals)) {
 	    /*
@@ -422,20 +421,18 @@ TclObjLookupVar(
 	useGlobal = (cachedNsPtr == iPtr->globalNsPtr) && (
 		(flags & TCL_GLOBAL_ONLY) ||
 		(*part1==':' && *(part1+1)==':') ||
-		(varFramePtr == NULL) ||
 		(!(varFramePtr->isProcCallFrame & FRAME_IS_PROC)
 			&& (nsPtr == iPtr->globalNsPtr)));
 
 	useReference = useGlobal || ((cachedNsPtr == nsPtr) && (
 		(flags & TCL_NAMESPACE_ONLY) ||
-		(varFramePtr &&
-		!(varFramePtr->isProcCallFrame & FRAME_IS_PROC) &&
-		!(flags & TCL_GLOBAL_ONLY) &&
+		(!(varFramePtr->isProcCallFrame & FRAME_IS_PROC) &&
+			!(flags & TCL_GLOBAL_ONLY) &&
 		/*
 		 * Careful: an undefined ns variable could be hiding a valid
 		 * global reference.
 		 */
-		!TclIsVarUndefined(varPtr))));
+			!TclIsVarUndefined(varPtr))));
 
 	if (useReference && (varPtr->hPtr != NULL)) {
 	    /*
@@ -689,7 +686,7 @@ TclLookupSimpleVar(
     varNsPtr = NULL;		/* set non-NULL if a nonlocal variable */
     *indexPtr = -3;
 
-    if ((flags & TCL_GLOBAL_ONLY) || iPtr->varFramePtr == NULL) {
+    if (flags & TCL_GLOBAL_ONLY) {
 	cxtNsPtr = iPtr->globalNsPtr;
     } else {
 	cxtNsPtr = iPtr->varFramePtr->nsPtr;
@@ -744,7 +741,6 @@ TclLookupSimpleVar(
      */
 
     if (((flags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY)) != 0)
-	    || (varFramePtr == NULL)
 	    || !(varFramePtr->isProcCallFrame & FRAME_IS_PROC)
 	    || (strstr(varName, "::") != NULL)) {
 	CONST char *tail;
@@ -3214,6 +3210,10 @@ ObjMakeUpvar(
      * interpreter in order to use TclObjLookupVar.
      */
 
+    if (framePtr == NULL) {
+	framePtr = iPtr->rootFramePtr;
+    }
+    
     varFramePtr = iPtr->varFramePtr;
     if (!(otherFlags & TCL_NAMESPACE_ONLY)) {
 	iPtr->varFramePtr = framePtr;
@@ -3553,8 +3553,7 @@ Tcl_GlobalObjCmd(
      * If we are not executing inside a Tcl procedure, just return.
      */
 
-    if ((iPtr->varFramePtr == NULL)
-	    || !(iPtr->varFramePtr->isProcCallFrame & FRAME_IS_PROC)) {
+    if (!(iPtr->varFramePtr->isProcCallFrame & FRAME_IS_PROC)) {
 	return TCL_OK;
     }
 
@@ -3705,8 +3704,7 @@ Tcl_VariableObjCmd(
 	 * linked to the new namespace variable "varName".
 	 */
 
-	if ((iPtr->varFramePtr != NULL)
-		&& (iPtr->varFramePtr->isProcCallFrame & FRAME_IS_PROC)) {
+	if (iPtr->varFramePtr->isProcCallFrame & FRAME_IS_PROC) {
 	    /*
 	     * varName might have a scope qualifier, but the name for the
 	     * local "link" variable must be the simple name at the tail.