merge trunk

21 files changed, 874 insertions, 1265 deletions

diff --git a/generic/regc_nfa.c b/generic/regc_nfa.c
index fc0c823..42489dd 100644
--- a/generic/regc_nfa.c
+++ b/generic/regc_nfa.c
@@ -824,7 +824,7 @@ duptraverse(
      * make all normal tests (not reg-33.14) pass.
      */
 #ifndef DUPTRAVERSE_MAX_DEPTH
-#define DUPTRAVERSE_MAX_DEPTH 700
+#define DUPTRAVERSE_MAX_DEPTH 15000
 #endif
 
     if (depth++ > DUPTRAVERSE_MAX_DEPTH) {
diff --git a/generic/regexec.c b/generic/regexec.c
index 9b6a693..ad4b6e6 100644
--- a/generic/regexec.c
+++ b/generic/regexec.c
@@ -504,12 +504,7 @@ complicatedFindLoop(
 		    return er;
 		}
 		if ((shorter) ? end == estop : end == begin) {
-		    /*
-		     * No point in trying again.
-		     */
-
-		    *coldp = cold;
-		    return REG_NOMATCH;
+		    break;
 		}
 
 		/*
diff --git a/generic/tclAssembly.c b/generic/tclAssembly.c
index 62641e6..100e9ef 100644
--- a/generic/tclAssembly.c
+++ b/generic/tclAssembly.c
@@ -930,6 +930,10 @@ TclCompileAssembleCmd(
 {
     Tcl_Token *tokenPtr;	/* Token in the input script */
 
+    int numCommands = envPtr->numCommands;
+    int offset = envPtr->codeNext - envPtr->codeStart;
+    int depth = envPtr->currStackDepth;
+
     /*
      * Make sure that the command has a single arg that is a simple word.
      */
@@ -943,10 +947,23 @@ TclCompileAssembleCmd(
     }
 
     /*
-     * Compile the code and return any error from the compilation.
+     * Compile the code and convert any error from the compilation into
+     * bytecode reporting the error;
      */
 
-    return TclAssembleCode(envPtr, tokenPtr[1].start, tokenPtr[1].size, 0);
+    if (TCL_ERROR == TclAssembleCode(envPtr, tokenPtr[1].start,
+	    tokenPtr[1].size, TCL_EVAL_DIRECT)) {
+
+	Tcl_AppendObjToErrorInfo(interp, Tcl_ObjPrintf(
+		"\n    (\"%.*s\" body, line %d)",
+		parsePtr->tokenPtr->size, parsePtr->tokenPtr->start,
+		Tcl_GetErrorLine(interp)));
+	envPtr->numCommands = numCommands;
+	envPtr->codeNext = envPtr->codeStart + offset;
+	envPtr->currStackDepth = depth;
+	TclCompileSyntaxError(interp, envPtr);
+    }
+    return TCL_OK;
 }
 
 /*
@@ -985,8 +1002,6 @@ TclAssembleCode(
 
     const char* instPtr = codePtr;
 				/* Where to start looking for a line of code */
-    int instLen;		/* Length in bytes of the current line of
-				 * code */
     const char* nextPtr;	/* Pointer to the end of the line of code */
     int bytesLeft = codeLen;	/* Number of bytes of source code remaining to
 				 * be parsed */
@@ -1000,10 +1015,6 @@ TclAssembleCode(
 	 */
 
 	status = Tcl_ParseCommand(interp, instPtr, bytesLeft, 0, parsePtr);
-	instLen = parsePtr->commandSize;
-	if (parsePtr->term == parsePtr->commandStart + instLen - 1) {
-	    --instLen;
-	}
 
 	/*
 	 * Report errors in the parse.
@@ -1012,7 +1023,7 @@ TclAssembleCode(
 	if (status != TCL_OK) {
 	    if (flags & TCL_EVAL_DIRECT) {
 		Tcl_LogCommandInfo(interp, codePtr, parsePtr->commandStart,
-			instLen);
+			parsePtr->term + 1 - parsePtr->commandStart);
 	    }
 	    FreeAssemblyEnv(assemEnvPtr);
 	    return TCL_ERROR;
@@ -1032,6 +1043,13 @@ TclAssembleCode(
 	 */
 
 	if (parsePtr->numWords > 0) {
+	    int instLen = parsePtr->commandSize;
+		    /* Length in bytes of the current command */
+
+	    if (parsePtr->term == parsePtr->commandStart + instLen - 1) {
+		--instLen;
+	    }
+
 	    /*
 	     * If tracing, show each line assembled as it happens.
 	     */
@@ -1107,7 +1125,7 @@ NewAssemblyEnv(
 
     assemEnvPtr->envPtr = envPtr;
     assemEnvPtr->parsePtr = parsePtr;
-    assemEnvPtr->cmdLine = envPtr->line;
+    assemEnvPtr->cmdLine = 1;
     assemEnvPtr->clNext = envPtr->clNext;
 
     /*
@@ -3029,7 +3047,7 @@ ResolveJumpTableTargets(
     auxDataIndex = TclGetInt4AtPtr(envPtr->codeStart + bbPtr->jumpOffset + 1);
     DEBUG_PRINT("bbPtr = %p jumpOffset = %d auxDataIndex = %d\n",
 	    bbPtr, bbPtr->jumpOffset, auxDataIndex);
-    realJumpTablePtr = envPtr->auxDataArrayPtr[auxDataIndex].clientData;
+    realJumpTablePtr = TclFetchAuxData(envPtr, auxDataIndex);
     realJumpHashPtr = &realJumpTablePtr->hashTable;
 
     /*
diff --git a/generic/tclBasic.c b/generic/tclBasic.c
index f805a94..7c664be 100644
--- a/generic/tclBasic.c
+++ b/generic/tclBasic.c
@@ -127,8 +127,6 @@ static Tcl_ObjCmdProc	ExprSqrtFunc;
 static Tcl_ObjCmdProc	ExprSrandFunc;
 static Tcl_ObjCmdProc	ExprUnaryFunc;
 static Tcl_ObjCmdProc	ExprWideFunc;
-static Tcl_Obj *	GetCommandSource(Interp *iPtr, int objc,
-			    Tcl_Obj *const objv[], int lookup);
 static void		MathFuncWrongNumArgs(Tcl_Interp *interp, int expected,
 			    int actual, Tcl_Obj *const *objv);
 static Tcl_NRPostProc	NRCoroutineCallerCallback;
@@ -149,7 +147,7 @@ static inline Command *	TEOV_LookupCmdFromObj(Tcl_Interp *interp,
 static int		TEOV_NotFound(Tcl_Interp *interp, int objc,
 			    Tcl_Obj *const objv[], Namespace *lookupNsPtr);
 static int		TEOV_RunEnterTraces(Tcl_Interp *interp,
-			    Command **cmdPtrPtr, int objc,
+			    Command **cmdPtrPtr, Tcl_Obj *commandPtr, int objc,
 			    Tcl_Obj *const objv[], Namespace *lookupNsPtr);
 static Tcl_NRPostProc	RewindCoroutineCallback;
 static Tcl_NRPostProc	TailcallCleanup;
@@ -1611,8 +1609,6 @@ DeleteInterpProc(
 	    ckfree(eclPtr->loc);
 	}
 
-	Tcl_DeleteHashTable(&eclPtr->litInfo);
-
 	ckfree(eclPtr);
 	Tcl_DeleteHashEntry(hPtr);
     }
@@ -2178,12 +2174,8 @@ Tcl_CreateCommand(
  *	future calls to Tcl_GetCommandName.
  *
  * Side effects:
- *	If no command named "cmdName" already exists for interp, one is
- *	created. Otherwise, if a command does exist, then if the object-based
- *	Tcl_ObjCmdProc is TclInvokeStringCommand, we assume Tcl_CreateCommand
- *	was called previously for the same command and just set its
- *	Tcl_ObjCmdProc to the argument "proc"; otherwise, we delete the old
- *	command.
+ *	If a command named "cmdName" already exists for interp, it is
+ * 	first deleted.  Then the new command is created from the arguments.
  *
  *	In the future, during bytecode evaluation when "cmdName" is seen as
  *	the name of a command by Tcl_EvalObj or Tcl_Eval, the object-based
@@ -2251,21 +2243,7 @@ Tcl_CreateObjCommand(
 	cmdPtr = Tcl_GetHashValue(hPtr);
 
 	/*
-	 * Command already exists. If its object-based Tcl_ObjCmdProc is
-	 * TclInvokeStringCommand, we just set its Tcl_ObjCmdProc to the
-	 * argument "proc". Otherwise, we delete the old command.
-	 */
-
-	if (cmdPtr->objProc == TclInvokeStringCommand) {
-	    cmdPtr->objProc = proc;
-	    cmdPtr->objClientData = clientData;
-	    cmdPtr->deleteProc = deleteProc;
-	    cmdPtr->deleteData = clientData;
-	    return (Tcl_Command) cmdPtr;
-	}
-
-	/*
-	 * Otherwise, we delete the old command. Be careful to preserve any
+	 * Command already exists; delete it. Be careful to preserve any
 	 * existing import links so we can restore them down below. That way,
 	 * you can redefine a command and its import status will remain
 	 * intact.
@@ -2413,8 +2391,8 @@ TclInvokeStringCommand(
  *	A standard Tcl string result value.
  *
  * Side effects:
- *	Besides those side effects of the called Tcl_CmdProc,
- *	TclInvokeStringCommand allocates and frees storage.
+ *	Besides those side effects of the called Tcl_ObjCmdProc,
+ *	TclInvokeObjectCommand allocates and frees storage.
  *
  *----------------------------------------------------------------------
  */
@@ -3357,66 +3335,6 @@ CancelEvalProc(
 /*
  *----------------------------------------------------------------------
  *
- * GetCommandSource --
- *
- *	This function returns a Tcl_Obj with the full source string for the
- *	command. This insures that traces get a correct NUL-terminated command
- *	string. The Tcl_Obj has refCount==1.
- *
- *	*** MAINTAINER WARNING ***
- *	The returned Tcl_Obj is all wrong for any purpose but getting the
- *	source string for an objc/objv command line in the stringRep (no
- *	stringRep if no source is available) and the corresponding substituted
- *	version in the List intrep.
- *	This means that the intRep and stringRep DO NOT COINCIDE! Using these
- *	Tcl_Objs normally is likely to break things.
- *
- *----------------------------------------------------------------------
- */
-
-static Tcl_Obj *
-GetCommandSource(
-    Interp *iPtr,
-    int objc,
-    Tcl_Obj *const objv[],
-    int lookup)
-{
-    Tcl_Obj *objPtr, *obj2Ptr;
-    CmdFrame *cfPtr = iPtr->cmdFramePtr;
-    const char *command = NULL;
-    int numChars;
-
-    objPtr = Tcl_NewListObj(objc, objv);
-    if (lookup && cfPtr && (cfPtr->numLevels == iPtr->numLevels-1)) {
-	switch (cfPtr->type) {
-	case TCL_LOCATION_EVAL:
-	case TCL_LOCATION_SOURCE:
-	    command = cfPtr->cmd.str.cmd;
-	    numChars = cfPtr->cmd.str.len;
-	    break;
-	case TCL_LOCATION_BC:
-	case TCL_LOCATION_PREBC:
-	    command = TclGetSrcInfoForCmd(iPtr, &numChars);
-	    break;
-	case TCL_LOCATION_EVAL_LIST:
-	    /* Got it already */
-	    break;
-	}
-	if (command) {
-	    obj2Ptr = Tcl_NewStringObj(command, numChars);
-	    objPtr->bytes = obj2Ptr->bytes;
-	    objPtr->length = numChars;
-	    obj2Ptr->bytes = NULL;
-	    Tcl_DecrRefCount(obj2Ptr);
-	}
-    }
-    Tcl_IncrRefCount(objPtr);
-    return objPtr;
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * TclCleanupCommand --
  *
  *	This function frees up a Command structure unless it is still
@@ -4269,13 +4187,15 @@ TclNREvalObjv(
 	 * necessary.
 	 */
 
-	result = TEOV_RunEnterTraces(interp, &cmdPtr, objc, objv, lookupNsPtr);
-	if (!cmdPtr) {
-	    return TEOV_NotFound(interp, objc, objv, lookupNsPtr);
-	}
+	result = TEOV_RunEnterTraces(interp, &cmdPtr, TclGetSourceFromFrame(
+		flags & TCL_EVAL_SOURCE_IN_FRAME ?  iPtr->cmdFramePtr : NULL,
+		objc, objv), objc, objv, lookupNsPtr);
 	if (result != TCL_OK) {
 	    return result;
 	}
+	if (!cmdPtr) {
+	    return TEOV_NotFound(interp, objc, objv, lookupNsPtr);
+	}
     }
 
 
@@ -4683,6 +4603,7 @@ static int
 TEOV_RunEnterTraces(
     Tcl_Interp *interp,
     Command **cmdPtrPtr,
+    Tcl_Obj *commandPtr,
     int objc,
     Tcl_Obj *const objv[],
     Namespace *lookupNsPtr)
@@ -4694,9 +4615,8 @@ TEOV_RunEnterTraces(
     int newEpoch;
     const char *command;
     int length;
-    Tcl_Obj *commandPtr;
 
-    commandPtr = GetCommandSource(iPtr, objc, objv, 1);
+    Tcl_IncrRefCount(commandPtr);
     command = Tcl_GetStringFromObj(commandPtr, &length);
 
     /*
@@ -4729,13 +4649,13 @@ TEOV_RunEnterTraces(
 	*cmdPtrPtr = cmdPtr;
     }
 
-    if (cmdPtr) {
+    if (cmdPtr && (traceCode == TCL_OK)) {
 	/*
 	 * Command was found: push a record to schedule the leave traces.
 	 */
 
-	TclNRAddCallback(interp, TEOV_RunLeaveTraces, INT2PTR(traceCode),
-		commandPtr, cmdPtr, NULL);
+	TclNRAddCallback(interp, TEOV_RunLeaveTraces, INT2PTR(objc),
+		commandPtr, cmdPtr, objv);
 	cmdPtr->refCount++;
     } else {
 	Tcl_DecrRefCount(commandPtr);
@@ -4750,20 +4670,18 @@ TEOV_RunLeaveTraces(
     int result)
 {
     Interp *iPtr = (Interp *) interp;
-    const char *command;
-    int length, objc;
-    Tcl_Obj **objv;
-    int traceCode = PTR2INT(data[0]);
+    int traceCode = TCL_OK;
+    int objc = PTR2INT(data[0]);
     Tcl_Obj *commandPtr = data[1];
     Command *cmdPtr = data[2];
+    Tcl_Obj **objv = data[3];
 
-    command = Tcl_GetStringFromObj(commandPtr, &length);
-    if (TCL_OK != Tcl_ListObjGetElements(interp, commandPtr, &objc, &objv)) {
-	Tcl_Panic("Who messed with commandPtr?");
-    }
 
     if (!(cmdPtr->flags & CMD_IS_DELETED)) {
-	if ((cmdPtr->flags & CMD_HAS_EXEC_TRACES) && traceCode == TCL_OK){
+	int length;
+	const char *command = Tcl_GetStringFromObj(commandPtr, &length);
+
+	if (cmdPtr->flags & CMD_HAS_EXEC_TRACES){
 	    traceCode = TclCheckExecutionTraces(interp, command, length,
 		    cmdPtr, result, TCL_TRACE_LEAVE_EXEC, objc, objv);
 	}
@@ -5019,31 +4937,22 @@ TclEvalEx(
     /*
      * TIP #280 Initialize tracking. Do not push on the frame stack yet.
      *
-     * We may continue counting based on a specific context (CTX), or open a
-     * new context, either for a sourced script, or 'eval'. For sourced files
-     * we always have a path object, even if nothing was specified in the
-     * interp itself. That makes code using it simpler as NULL checks can be
-     * left out. Sourced file without path in the 'scriptFile' is possible
-     * during Tcl initialization.
+     * We open a new context, either for a sourced script, or 'eval'.
+     * For sourced files we always have a path object, even if nothing was
+     * specified in the interp itself. That makes code using it simpler as
+     * NULL checks can be left out. Sourced file without path in the
+     * 'scriptFile' is possible during Tcl initialization.
      */
 
     eeFramePtr->level = iPtr->cmdFramePtr ? iPtr->cmdFramePtr->level + 1 : 1;
-    eeFramePtr->numLevels = iPtr->numLevels;
     eeFramePtr->framePtr = iPtr->framePtr;
     eeFramePtr->nextPtr = iPtr->cmdFramePtr;
     eeFramePtr->nline = 0;
     eeFramePtr->line = NULL;
+    eeFramePtr->cmdObj = NULL;
 
     iPtr->cmdFramePtr = eeFramePtr;
-    if (iPtr->evalFlags & TCL_EVAL_CTX) {
-	/*
-	 * Path information comes out of the context.
-	 */
-
-	eeFramePtr->type = TCL_LOCATION_SOURCE;
-	eeFramePtr->data.eval.path = iPtr->invokeCmdFramePtr->data.eval.path;
-	Tcl_IncrRefCount(eeFramePtr->data.eval.path);
-    } else if (iPtr->evalFlags & TCL_EVAL_FILE) {
+    if (iPtr->evalFlags & TCL_EVAL_FILE) {
 	/*
 	 * Set up for a sourced file.
 	 */
@@ -5086,7 +4995,9 @@ TclEvalEx(
     do {
 	if (Tcl_ParseCommand(interp, p, bytesLeft, 0, parsePtr) != TCL_OK) {
 	    code = TCL_ERROR;
-	    goto error;
+	    Tcl_LogCommandInfo(interp, script, parsePtr->commandStart,
+		    parsePtr->term + 1 - parsePtr->commandStart);
+	    goto posterror;
 	}
 
 	/*
@@ -5252,23 +5163,28 @@ TclEvalEx(
 	     * have been executed.
 	     */
 
-	    eeFramePtr->cmd.str.cmd = parsePtr->commandStart;
-	    eeFramePtr->cmd.str.len = parsePtr->commandSize;
+	    eeFramePtr->cmd = parsePtr->commandStart;
+	    eeFramePtr->len = parsePtr->commandSize;
 
 	    if (parsePtr->term ==
 		    parsePtr->commandStart + parsePtr->commandSize - 1) {
-		eeFramePtr->cmd.str.len--;
+		eeFramePtr->len--;
 	    }
 
 	    eeFramePtr->nline = objectsUsed;
 	    eeFramePtr->line = lines;
 
 	    TclArgumentEnter(interp, objv, objectsUsed, eeFramePtr);
-	    code = Tcl_EvalObjv(interp, objectsUsed, objv, TCL_EVAL_NOERR);
+	    code = Tcl_EvalObjv(interp, objectsUsed, objv,
+		    TCL_EVAL_NOERR | TCL_EVAL_SOURCE_IN_FRAME);
 	    TclArgumentRelease(interp, objv, objectsUsed);
 
 	    eeFramePtr->line = NULL;
 	    eeFramePtr->nline = 0;
+	    if (eeFramePtr->cmdObj) {
+		Tcl_DecrRefCount(eeFramePtr->cmdObj);
+		eeFramePtr->cmdObj = NULL;
+	    }
 
 	    if (code != TCL_OK) {
 		goto error;
@@ -5342,6 +5258,7 @@ TclEvalEx(
 	Tcl_LogCommandInfo(interp, script, parsePtr->commandStart,
 		commandLength);
     }
+ posterror:
     iPtr->flags &= ~ERR_ALREADY_LOGGED;
 
     /*
@@ -5616,76 +5533,88 @@ TclArgumentBCEnter(
     int objc,
     void *codePtr,
     CmdFrame *cfPtr,
+    int cmd,
     int pc)
 {
+    ExtCmdLoc *eclPtr;
+    int word;
+    ECL *ePtr;
+    CFWordBC *lastPtr = NULL;
     Interp *iPtr = (Interp *) interp;
     Tcl_HashEntry *hePtr =
 	    Tcl_FindHashEntry(iPtr->lineBCPtr, (char *) codePtr);
-    ExtCmdLoc *eclPtr;
 
     if (!hePtr) {
 	return;
     }
     eclPtr = Tcl_GetHashValue(hePtr);
-    hePtr = Tcl_FindHashEntry(&eclPtr->litInfo, INT2PTR(pc));
-    if (hePtr) {
-	int word;
-	int cmd = PTR2INT(Tcl_GetHashValue(hePtr));
-	ECL *ePtr = &eclPtr->loc[cmd];
-	CFWordBC *lastPtr = NULL;
+    ePtr = &eclPtr->loc[cmd];
 
-	/*
-	 * A few truths ...
-	 * (1) ePtr->nline == objc
-	 * (2) (ePtr->line[word] < 0) => !literal, for all words
-	 * (3) (word == 0) => !literal
-	 *
-	 * Item (2) is why we can use objv to get the literals, and do not
-	 * have to save them at compile time.
-	 */
+    /*
+     * ePtr->nline is the number of words originally parsed.
+     *
+     * objc is the number of elements getting invoked.
+     *
+     * If they are not the same, we arrived here by compiling an
+     * ensemble dispatch.  Ensemble subcommands that lead to script
+     * evaluation are not supposed to get compiled, because a command
+     * such as [info level] in the script can expose some of the dispatch
+     * shenanigans.  This means that we don't have to tend to the 
+     * housekeeping, and can escape now.
+     */
+	
+    if (ePtr->nline != objc) {
+        return;
+    }
 
-        if (ePtr->nline != objc) {
-            Tcl_Panic ("TIP 280 data structure inconsistency");
-        }
+    /*
+     * Having disposed of the ensemble cases, we can state...
+     * A few truths ...
+     * (1) ePtr->nline == objc
+     * (2) (ePtr->line[word] < 0) => !literal, for all words
+     * (3) (word == 0) => !literal
+     *
+     * Item (2) is why we can use objv to get the literals, and do not
+     * have to save them at compile time.
+     */
 
-	for (word = 1; word < objc; word++) {
-	    if (ePtr->line[word] >= 0) {
-		int isnew;
-		Tcl_HashEntry *hPtr = Tcl_CreateHashEntry(iPtr->lineLABCPtr,
-			objv[word], &isnew);
-		CFWordBC *cfwPtr = ckalloc(sizeof(CFWordBC));
-
-		cfwPtr->framePtr = cfPtr;
-		cfwPtr->obj = objv[word];
-		cfwPtr->pc = pc;
-		cfwPtr->word = word;
-		cfwPtr->nextPtr = lastPtr;
-		lastPtr = cfwPtr;
-
-		if (isnew) {
-		    /*
-		     * The word is not on the stack yet, remember the current
-		     * location and initialize references.
-		     */
-
-		    cfwPtr->prevPtr = NULL;
-		} else {
-		    /*
-		     * The object is already on the stack, however it may have
-		     * a different location now (literal sharing may map
-		     * multiple location to a single Tcl_Obj*. Save the old
-		     * information in the new structure.
-		     */
-
-		    cfwPtr->prevPtr = Tcl_GetHashValue(hPtr);
-		}
+    for (word = 1; word < objc; word++) {
+	if (ePtr->line[word] >= 0) {
+	    int isnew;
+	    Tcl_HashEntry *hPtr = Tcl_CreateHashEntry(iPtr->lineLABCPtr,
+		objv[word], &isnew);
+	    CFWordBC *cfwPtr = ckalloc(sizeof(CFWordBC));
+
+	    cfwPtr->framePtr = cfPtr;
+	    cfwPtr->obj = objv[word];
+	    cfwPtr->pc = pc;
+	    cfwPtr->word = word;
+	    cfwPtr->nextPtr = lastPtr;
+	    lastPtr = cfwPtr;
+
+	    if (isnew) {
+		/*
+		 * The word is not on the stack yet, remember the current
+		 * location and initialize references.
+		 */
+
+		cfwPtr->prevPtr = NULL;
+	    } else {
+		/*
+		 * The object is already on the stack, however it may have
+		 * a different location now (literal sharing may map
+		 * multiple location to a single Tcl_Obj*. Save the old
+		 * information in the new structure.
+		 */
 
-		Tcl_SetHashValue(hPtr, cfwPtr);
+		cfwPtr->prevPtr = Tcl_GetHashValue(hPtr);
 	    }
-	} /* for */
 
-	cfPtr->litarg = lastPtr;
-    } /* if */
+	    Tcl_SetHashValue(hPtr, cfwPtr);
+	}
+    } /* for */
+
+    cfPtr->litarg = lastPtr;
 }
 
 /*
@@ -5895,6 +5824,11 @@ Tcl_GlobalEvalObj(
  *	compiled into bytecodes if necessary, unless TCL_EVAL_DIRECT is
  *	specified.
  *
+ *	If the flag TCL_EVAL_DIRECT is passed in, the value of invoker
+ *	must be NULL.  Support for non-NULL invokers in that mode has
+ *	been removed since it was unused and untested.  Failure to 
+ *	follow this limitation will lead to an assertion panic.
+ *
  * Results:
  *	The return value is one of the return codes defined in tcl.h (such as
  *	TCL_OK), and the interpreter's result contains a value to supplement
@@ -5963,13 +5897,12 @@ TclNREvalObjEx(
      */
 
     if (TclListObjIsCanonical(objPtr)) {
-	Tcl_Obj *listPtr = objPtr;
 	CmdFrame *eoFramePtr = NULL;
 	int objc;
-	Tcl_Obj **objv;
+	Tcl_Obj *listPtr, **objv;
 
 	/*
-	 * Pure List Optimization (no string representation). In this case, we
+	 * Canonical List Optimization:  In this case, we
 	 * can safely use Tcl_EvalObjv instead and get an appreciable
 	 * improvement in execution speed. This is because it allows us to
 	 * avoid a setFromAny step that would just pack everything into a
@@ -5977,11 +5910,6 @@ TclNREvalObjEx(
 	 *
 	 * This also preserves any associations between list elements and
 	 * location information for such elements.
-	 *
-	 * This restriction has been relaxed a bit by storing in lists whether
-	 * they are "canonical" or not (a canonical list being one that is
-	 * either pure or that has its string rep derived by
-	 * UpdateStringOfList from the internal rep).
 	 */
 
 	/*
@@ -5990,13 +5918,13 @@ TclNREvalObjEx(
 	 * we always make a copy. The callback takes care od the refCounts for
 	 * both listPtr and objPtr.
 	 *
+	 * TODO: Create a test to demo this need, or eliminate it.
 	 * FIXME OPT: preserve just the internal rep?
 	 */
 
 	Tcl_IncrRefCount(objPtr);
 	listPtr = TclListObjCopy(interp, objPtr);
 	Tcl_IncrRefCount(listPtr);
-	TclDecrRefCount(objPtr);
 
 	if (word != INT_MIN) {
 	    /*
@@ -6019,22 +5947,25 @@ TclNREvalObjEx(
 	    eoFramePtr->nline = 0;
 	    eoFramePtr->line = NULL;
 
-	    eoFramePtr->type = TCL_LOCATION_EVAL_LIST;
+	    eoFramePtr->type = TCL_LOCATION_EVAL;
 	    eoFramePtr->level = (iPtr->cmdFramePtr == NULL?
 		    1 : iPtr->cmdFramePtr->level + 1);
-	    eoFramePtr->numLevels = iPtr->numLevels;
 	    eoFramePtr->framePtr = iPtr->framePtr;
 	    eoFramePtr->nextPtr = iPtr->cmdFramePtr;
 
-	    eoFramePtr->cmd.listPtr = listPtr;
+	    eoFramePtr->cmdObj = objPtr;
+	    eoFramePtr->cmd = NULL;
+	    eoFramePtr->len = 0;
 	    eoFramePtr->data.eval.path = NULL;
 
 	    iPtr->cmdFramePtr = eoFramePtr;
+
+	    flags |= TCL_EVAL_SOURCE_IN_FRAME;
 	}
 
 	TclMarkTailcall(interp);
         TclNRAddCallback(interp, TEOEx_ListCallback, listPtr, eoFramePtr,
-		NULL, NULL);
+		objPtr, NULL);
 
 	ListObjGetElements(listPtr, objc, objv);
 	return TclNREvalObjv(interp, objc, objv, flags, NULL);
@@ -6074,14 +6005,6 @@ TclNREvalObjEx(
 	 * We're not supposed to use the compiler or byte-code
 	 * interpreter. Let Tcl_EvalEx evaluate the command directly (and
 	 * probably more slowly).
-	 *
-	 * TIP #280. Propagate context as much as we can. Especially if the
-	 * script to evaluate is a single literal it makes sense to look if
-	 * our context is one with absolute line numbers we can then track
-	 * into the literal itself too.
-	 *
-	 * See also tclCompile.c, TclInitCompileEnv, for the equivalent code
-	 * in the bytecode compiler.
 	 */
 
 	const char *script;
@@ -6105,92 +6028,19 @@ TclNREvalObjEx(
 	 */
 
 	ContLineLoc *saveCLLocPtr = iPtr->scriptCLLocPtr;
-	ContLineLoc *clLocPtr = TclContinuationsGet(objPtr);
-
-	if (clLocPtr) {
-	    iPtr->scriptCLLocPtr = clLocPtr;
-	    Tcl_Preserve(iPtr->scriptCLLocPtr);
-	} else {
-	    iPtr->scriptCLLocPtr = NULL;
-	}
-
-	Tcl_IncrRefCount(objPtr);
-	if (invoker == NULL) {
-	    /*
-	     * No context, force opening of our own.
-	     */
 
-	    script = Tcl_GetStringFromObj(objPtr, &numSrcBytes);
-	    result = Tcl_EvalEx(interp, script, numSrcBytes, flags);
-	} else {
-	    /*
-	     * We have an invoker, describing the command asking for the
-	     * evaluation of a subordinate script. This script may originate
-	     * in a literal word, or from a variable, etc. Using the line
-	     * array we now check if we have good line information for the
-	     * relevant word. The type of context is relevant as well. In a
-	     * non-'source' context we don't have to try tracking lines.
-	     *
-	     * First see if the word exists and is a literal. If not we go
-	     * through the easy dynamic branch. No need to perform more
-	     * complex invokations.
-	     */
-
-	    int pc = 0;
-	    CmdFrame *ctxPtr = TclStackAlloc(interp, sizeof(CmdFrame));
-
-	    *ctxPtr = *invoker;
-	    if (invoker->type == TCL_LOCATION_BC) {
-		/*
-		 * Note: Type BC => ctxPtr->data.eval.path is not used.
-		 * ctxPtr->data.tebc.codePtr is used instead.
-		 */
-
-		TclGetSrcInfoForPc(ctxPtr);
-		pc = 1;
-	    }
-
-	    script = Tcl_GetStringFromObj(objPtr, &numSrcBytes);
-
-	    if ((invoker->nline <= word) ||
-		    (invoker->line[word] < 0) ||
-		    (ctxPtr->type != TCL_LOCATION_SOURCE)) {
-		/*
-		 * Dynamic script, or dynamic context, force our own context.
-		 */
+	assert(invoker == NULL);
 
-		result = Tcl_EvalEx(interp, script, numSrcBytes, flags);
-	    } else {
-		/*
-		 * Absolute context to reuse.
-		 */
-
-		iPtr->invokeCmdFramePtr = ctxPtr;
-		iPtr->evalFlags |= TCL_EVAL_CTX;
+	iPtr->scriptCLLocPtr = TclContinuationsGet(objPtr);
 
-		result = TclEvalEx(interp, script, numSrcBytes, flags,
-			ctxPtr->line[word], NULL, script);
-	    }
-	    if (pc && (ctxPtr->type == TCL_LOCATION_SOURCE)) {
-		/*
-		 * Death of SrcInfo reference.
-		 */
+	Tcl_IncrRefCount(objPtr);
 
-		Tcl_DecrRefCount(ctxPtr->data.eval.path);
-	    }
-	    TclStackFree(interp, ctxPtr);
-	}
+	script = Tcl_GetStringFromObj(objPtr, &numSrcBytes);
+	result = Tcl_EvalEx(interp, script, numSrcBytes, flags);
 
-	/*
-	 * Now release the lock on the continuation line information, if any,
-	 * and restore the caller's settings.
-	 */
+	TclDecrRefCount(objPtr);
 
-	if (iPtr->scriptCLLocPtr) {
-	    Tcl_Release(iPtr->scriptCLLocPtr);
-	}
 	iPtr->scriptCLLocPtr = saveCLLocPtr;
-	TclDecrRefCount(objPtr);
 	return result;
     }
 }
@@ -6250,6 +6100,7 @@ TEOEx_ListCallback(
     Interp *iPtr = (Interp *) interp;
     Tcl_Obj *listPtr = data[0];
     CmdFrame *eoFramePtr = data[1];
+    Tcl_Obj *objPtr = data[2];
 
     /*
      * Remove the cmdFrame
@@ -6259,6 +6110,7 @@ TEOEx_ListCallback(
 	iPtr->cmdFramePtr = eoFramePtr->nextPtr;
 	TclStackFree(interp, eoFramePtr);
     }
+    TclDecrRefCount(objPtr);
     TclDecrRefCount(listPtr);
 
     return result;
diff --git a/generic/tclCmdIL.c b/generic/tclCmdIL.c
index 0e33392..fa4ead4 100644
--- a/generic/tclCmdIL.c
+++ b/generic/tclCmdIL.c
@@ -1302,28 +1302,12 @@ TclInfoFrame(
 	 */
 
 	ADD_PAIR("type", Tcl_NewStringObj(typeString[framePtr->type], -1));
-	ADD_PAIR("line", Tcl_NewIntObj(framePtr->line[0]));
-	ADD_PAIR("cmd", Tcl_NewStringObj(framePtr->cmd.str.cmd,
-		framePtr->cmd.str.len));
-	break;
-
-    case TCL_LOCATION_EVAL_LIST:
-	/*
-	 * List optimized evaluation. Type, line, cmd, the latter through
-	 * listPtr, possibly a frame.
-	 */
-
-	ADD_PAIR("type", Tcl_NewStringObj(typeString[framePtr->type], -1));
-	ADD_PAIR("line", Tcl_NewIntObj(1));
-
-	/*
-	 * We put a duplicate of the command list obj into the result to
-	 * ensure that the 'pure List'-property of the command itself is not
-	 * destroyed. Otherwise the query here would disable the list
-	 * optimization path in Tcl_EvalObjEx.
-	 */
-
-	ADD_PAIR("cmd", Tcl_DuplicateObj(framePtr->cmd.listPtr));
+	if (framePtr->line) {
+	    ADD_PAIR("line", Tcl_NewIntObj(framePtr->line[0]));
+	} else {
+	    ADD_PAIR("line", Tcl_NewIntObj(1));
+	}
+	ADD_PAIR("cmd", TclGetSourceFromFrame(framePtr, 0, NULL));
 	break;
 
     case TCL_LOCATION_PREBC:
@@ -1371,8 +1355,7 @@ TclInfoFrame(
 	    Tcl_DecrRefCount(fPtr->data.eval.path);
 	}
 
-	ADD_PAIR("cmd",
-		Tcl_NewStringObj(fPtr->cmd.str.cmd, fPtr->cmd.str.len));
+	ADD_PAIR("cmd", TclGetSourceFromFrame(fPtr, 0, NULL));
 	TclStackFree(interp, fPtr);
 	break;
     }
@@ -1391,8 +1374,7 @@ TclInfoFrame(
 	 * the result list object.
 	 */
 
-	ADD_PAIR("cmd", Tcl_NewStringObj(framePtr->cmd.str.cmd,
-		framePtr->cmd.str.len));
+	ADD_PAIR("cmd", TclGetSourceFromFrame(framePtr, 0, NULL));
 	break;
 
     case TCL_LOCATION_PROC:
diff --git a/generic/tclCompCmds.c b/generic/tclCompCmds.c
index 0740490..2a6f88d 100644
--- a/generic/tclCompCmds.c
+++ b/generic/tclCompCmds.c
@@ -95,6 +95,7 @@ TclCompileAppendCmd(
     int isScalar, localIndex, numWords, i;
     DefineLineInformation;	/* TIP #280 */
 
+    /* TODO: Consider support for compiling expanded args. */
     numWords = parsePtr->numWords;
     if (numWords == 1) {
 	return TCL_ERROR;
@@ -552,7 +553,6 @@ TclCompileCatchCmd(
     JumpFixup jumpFixup;
     Tcl_Token *cmdTokenPtr, *resultNameTokenPtr, *optsNameTokenPtr;
     int resultIndex, optsIndex, range;
-    int initStackDepth = envPtr->currStackDepth;
     DefineLineInformation;	/* TIP #280 */
 
     /*
@@ -618,12 +618,12 @@ TclCompileCatchCmd(
      * begin by undeflowing the stack below the mark set by BEGIN_CATCH4.
      */
 
-    SetLineInformation(1);
     if (cmdTokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
 	TclEmitInstInt4(	INST_BEGIN_CATCH4, range,	envPtr);
 	ExceptionRangeStarts(envPtr, range);
-	CompileBody(envPtr, cmdTokenPtr, interp);
+	BODY(cmdTokenPtr, 1);
     } else {
+	SetLineInformation(1);
 	CompileTokens(envPtr, cmdTokenPtr, interp);
 	TclEmitInstInt4(	INST_BEGIN_CATCH4, range,	envPtr);
 	ExceptionRangeStarts(envPtr, range);
@@ -750,15 +750,6 @@ TclCompileCatchCmd(
 	TclEmitOpcode(		INST_POP,			envPtr);
     }
 
-    /* 
-     * Result of all this, on either branch, should have been to leave one
-     * operand -- the return code -- on the stack.
-     */
-
-    if (envPtr->currStackDepth != initStackDepth + 1) {
-	Tcl_Panic("in TclCompileCatchCmd, currStackDepth = %d should be %d",
-		  envPtr->currStackDepth, initStackDepth+1);
-    }
     return TCL_OK;
 }
 
@@ -991,6 +982,7 @@ TclCompileDictGetCmd(
      * case is legal, but too special and magic for us to deal with here).
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords < 3) {
 	return TCL_ERROR;
     }
@@ -1028,6 +1020,7 @@ TclCompileDictExistsCmd(
      * case is legal, but too special and magic for us to deal with here).
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords < 3) {
 	return TCL_ERROR;
     }
@@ -1065,6 +1058,7 @@ TclCompileDictUnsetCmd(
      * compile to bytecode.
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords < 3) {
 	return TCL_ERROR;
     }
@@ -1210,6 +1204,7 @@ TclCompileDictMergeCmd(
      * argument, the only thing to do is to verify the dict-ness.
      */
 
+    /* TODO: Consider support for compiling expanded args. (less likely) */
     if (parsePtr->numWords < 2) {
 	PushStringLiteral(envPtr, "");
 	return TCL_OK;
@@ -1475,8 +1470,7 @@ CompileDictEachCmd(
      * Compile the loop body itself. It should be stack-neutral.
      */
 
-    SetLineInformation(3);
-    CompileBody(envPtr, bodyTokenPtr, interp);
+    BODY(bodyTokenPtr, 3);
     if (collect == TCL_EACH_COLLECT) {
 	Emit14Inst(	INST_LOAD_SCALAR, keyVarIndex,		envPtr);
 	TclEmitInstInt4(INST_OVER, 1,				envPtr);
@@ -1659,8 +1653,7 @@ TclCompileDictUpdateCmd(
     TclEmitInstInt4(	INST_BEGIN_CATCH4, range,		envPtr);
 
     ExceptionRangeStarts(envPtr, range);
-    SetLineInformation(parsePtr->numWords - 1);
-    CompileBody(envPtr, bodyTokenPtr, interp);
+    BODY(bodyTokenPtr, parsePtr->numWords - 1);
     ExceptionRangeEnds(envPtr, range);
 
     /*
@@ -1732,6 +1725,7 @@ TclCompileDictAppendCmd(
      * speed quite so much. ;-)
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords<4 || parsePtr->numWords>100) {
 	return TCL_ERROR;
     }
@@ -1784,6 +1778,8 @@ TclCompileDictLappendCmd(
      * There must be three arguments after the command.
      */
 
+    /* TODO: Consider support for compiling expanded args. */
+    /* Probably not.  Why is INST_DICT_LAPPEND limited to one value? */
     if (parsePtr->numWords != 4) {
 	return TCL_ERROR;
     }
@@ -1830,6 +1826,7 @@ TclCompileDictWithCmd(
      * There must be at least one argument after the command.
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords < 3) {
 	return TCL_ERROR;
     }
@@ -2000,8 +1997,7 @@ TclCompileDictWithCmd(
     TclEmitInstInt4(		INST_BEGIN_CATCH4, range,	envPtr);
 
     ExceptionRangeStarts(envPtr, range);
-    SetLineInformation(parsePtr->numWords-1);
-    CompileBody(envPtr, tokenPtr, interp);
+    BODY(tokenPtr, parsePtr->numWords - 1);
     ExceptionRangeEnds(envPtr, range);
 
     /*
@@ -2297,8 +2293,7 @@ TclCompileForCmd(
      * Inline compile the initial command.
      */
 
-    SetLineInformation(1);
-    CompileBody(envPtr, startTokenPtr, interp);
+    BODY(startTokenPtr, 1);
     TclEmitOpcode(INST_POP, envPtr);
 
     /*
@@ -2321,8 +2316,7 @@ TclCompileForCmd(
 
     bodyRange = TclCreateExceptRange(LOOP_EXCEPTION_RANGE, envPtr);
     bodyCodeOffset = ExceptionRangeStarts(envPtr, bodyRange);
-    SetLineInformation(4);
-    CompileBody(envPtr, bodyTokenPtr, interp);
+    BODY(bodyTokenPtr, 4);
     ExceptionRangeEnds(envPtr, bodyRange);
     TclEmitOpcode(INST_POP, envPtr);
 
@@ -2335,8 +2329,7 @@ TclCompileForCmd(
     nextRange = TclCreateExceptRange(LOOP_EXCEPTION_RANGE, envPtr);
     envPtr->exceptAuxArrayPtr[nextRange].supportsContinue = 0;
     nextCodeOffset = ExceptionRangeStarts(envPtr, nextRange);
-    SetLineInformation(3);
-    CompileBody(envPtr, nextTokenPtr, interp);
+    BODY(nextTokenPtr, 3);
     ExceptionRangeEnds(envPtr, nextRange);
     TclEmitOpcode(INST_POP, envPtr);
 
@@ -2493,7 +2486,7 @@ CompileEachloopCmd(
     Tcl_Token *tokenPtr, *bodyTokenPtr;
     unsigned char *jumpPc;
     JumpFixup jumpFalseFixup;
-    int jumpBackDist, jumpBackOffset, infoIndex, range, bodyIndex;
+    int jumpBackDist, jumpBackOffset, infoIndex, range;
     int numWords, numLists, numVars, loopIndex, tempVar, i, j, code;
     DefineLineInformation;	/* TIP #280 */
 
@@ -2533,8 +2526,6 @@ CompileEachloopCmd(
 	return TCL_ERROR;
     }
 
-    bodyIndex = i-1;
-
     /*
      * Allocate storage for the varcList and varvList arrays if necessary.
      */
@@ -2573,7 +2564,7 @@ CompileEachloopCmd(
 
 	Tcl_DStringInit(&varList);
 	TclDStringAppendToken(&varList, &tokenPtr[1]);
-	code = Tcl_SplitList(interp, Tcl_DStringValue(&varList),
+	code = Tcl_SplitList(NULL, Tcl_DStringValue(&varList),
 		&varcList[loopIndex], &varvList[loopIndex]);
 	Tcl_DStringFree(&varList);
 	if (code != TCL_OK) {
@@ -2675,8 +2666,7 @@ CompileEachloopCmd(
 	    i < numWords-1;
 	    i++, tokenPtr = TokenAfter(tokenPtr)) {
 	if ((i%2 == 0) && (i > 0)) {
-	    SetLineInformation(i);
-	    CompileTokens(envPtr, tokenPtr, interp);
+	    CompileWord(envPtr, tokenPtr, interp, i);
 	    tempVar = (firstValueTemp + loopIndex);
 	    Emit14Inst(		INST_STORE_SCALAR, tempVar,	envPtr);
 	    TclEmitOpcode(	INST_POP,			envPtr);
@@ -2713,9 +2703,8 @@ CompileEachloopCmd(
      * Inline compile the loop body.
      */
 
-    SetLineInformation(bodyIndex);
     ExceptionRangeStarts(envPtr, range);
-    CompileBody(envPtr, bodyTokenPtr, interp);
+    BODY(bodyTokenPtr, numWords - 1);
     ExceptionRangeEnds(envPtr, range);
 
     if (collect == TCL_EACH_COLLECT) {
@@ -3064,7 +3053,8 @@ TclCompileFormatCmd(
     ckfree(objv);
     Tcl_DecrRefCount(formatObj);
     if (tmpObj == NULL) {
-	return TCL_ERROR;
+	TclCompileSyntaxError(interp, envPtr);
+	return TCL_OK;
     }
 
     /*
@@ -3242,10 +3232,7 @@ TclPushVarName(
     CompileEnv *envPtr,		/* Holds resulting instructions. */
     int flags,			/* TCL_NO_LARGE_INDEX | TCL_NO_ELEMENT. */
     int *localIndexPtr,		/* Must not be NULL. */
-    int *isScalarPtr,		/* Must not be NULL. */
-    int line,			/* Line the token starts on. */
-    int *clNext)		/* Reference to offset of next hidden cont.
-				 * line. */
+    int *isScalarPtr)		/* Must not be NULL. */
 {
     register const char *p;
     const char *name, *elName;
@@ -3425,8 +3412,6 @@ TclPushVarName(
 
 	if (elName != NULL && !(flags & TCL_NO_ELEMENT)) {
 	    if (elNameChars) {
-		envPtr->line = line;
-		envPtr->clNext = clNext;
 		TclCompileTokens(interp, elemTokenPtr, elemTokenCount,
 			envPtr);
 	    } else {
@@ -3438,8 +3423,6 @@ TclPushVarName(
 	 * The var name isn't simple: compile and push it.
 	 */
 
-	envPtr->line = line;
-	envPtr->clNext = clNext;
 	CompileTokens(envPtr, varTokenPtr, interp);
     }
 
diff --git a/generic/tclCompCmdsGR.c b/generic/tclCompCmdsGR.c
index f7c15e6..150c378 100644
--- a/generic/tclCompCmdsGR.c
+++ b/generic/tclCompCmdsGR.c
@@ -60,6 +60,7 @@ TclCompileGlobalCmd(
     int localIndex, numWords, i;
     DefineLineInformation;	/* TIP #280 */
 
+    /* TODO: Consider support for compiling expanded args. */
     numWords = parsePtr->numWords;
     if (numWords < 2) {
 	return TCL_ERROR;
@@ -264,8 +265,7 @@ TclCompileIfCmd(
 	 */
 
 	if (compileScripts) {
-	    SetLineInformation(wordIdx);
-	    CompileBody(envPtr, tokenPtr, interp);
+	    BODY(tokenPtr, wordIdx);
 	}
 
 	if (realCond) {
@@ -345,8 +345,7 @@ TclCompileIfCmd(
 	     * Compile the else command body.
 	     */
 
-	    SetLineInformation(wordIdx);
-	    CompileBody(envPtr, tokenPtr, interp);
+	    BODY(tokenPtr, wordIdx);
 	}
 
 	/*
@@ -701,8 +700,7 @@ TclCompileInfoLevelCmd(
 	 * list of arguments.
 	 */
 
-	SetLineInformation(1);
-	CompileTokens(envPtr, TokenAfter(parsePtr->tokenPtr), interp);
+	CompileWord(envPtr, TokenAfter(parsePtr->tokenPtr), interp, 1);
 	TclEmitOpcode(		INST_INFO_LEVEL_ARGS,		envPtr);
     }
     return TCL_OK;
@@ -823,6 +821,7 @@ TclCompileLappendCmd(
 	return TCL_ERROR;
     }
 
+    /* TODO: Consider support for compiling expanded args. */
     numWords = parsePtr->numWords;
     if (numWords == 1) {
 	return TCL_ERROR;
@@ -1064,6 +1063,7 @@ TclCompileLindexCmd(
      * Quit if too few args.
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (numWords <= 1) {
 	return TCL_ERROR;
     }
@@ -1586,6 +1586,7 @@ TclCompileLsetCmd(
      * Check argument count.
      */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords < 3) {
 	/*
 	 * Fail at run time, not in compilation.
@@ -2534,6 +2535,7 @@ TclCompileSyntaxError(
     TclEmitPush(TclRegisterNewLiteral(envPtr, bytes, numBytes), envPtr);
     CompileReturnInternal(envPtr, INST_SYNTAX, TCL_ERROR, 0,
 	    TclNoErrorStack(interp, Tcl_GetReturnOptions(interp, TCL_ERROR)));
+    Tcl_ResetResult(interp);
 }
 
 /*
diff --git a/generic/tclCompCmdsSZ.c b/generic/tclCompCmdsSZ.c
index 3639032..0cab490 100644
--- a/generic/tclCompCmdsSZ.c
+++ b/generic/tclCompCmdsSZ.c
@@ -43,17 +43,14 @@ static int		CompileUnaryOpCmd(Tcl_Interp *interp,
 			    Tcl_Parse *parsePtr, int instruction,
 			    CompileEnv *envPtr);
 static void		IssueSwitchChainedTests(Tcl_Interp *interp,
-			    CompileEnv *envPtr, ExtCmdLoc *mapPtr,
-			    int eclIndex, int mode, int noCase,
-			    int valueIndex, Tcl_Token *valueTokenPtr,
-			    int numWords, Tcl_Token **bodyToken,
-			    int *bodyLines, int **bodyNext);
-static void		IssueSwitchJumpTable(Tcl_Interp *interp,
-			    CompileEnv *envPtr, ExtCmdLoc *mapPtr,
-			    int eclIndex, int valueIndex,
-			    Tcl_Token *valueTokenPtr, int numWords,
+			    CompileEnv *envPtr, int mode, int noCase,
+			    int valueIndex, int numWords,
 			    Tcl_Token **bodyToken, int *bodyLines,
-			    int **bodyContLines);
+			    int **bodyNext);
+static void		IssueSwitchJumpTable(Tcl_Interp *interp,
+			    CompileEnv *envPtr, int valueIndex,
+			    int numWords, Tcl_Token **bodyToken,
+			    int *bodyLines, int **bodyContLines);
 static int		IssueTryClausesInstructions(Tcl_Interp *interp,
 			    CompileEnv *envPtr, Tcl_Token *bodyToken,
 			    int numHandlers, int *matchCodes,
@@ -92,8 +89,6 @@ const AuxDataType tclJumptableInfoType = {
     TclEmitInstInt1(INST_##name,(val1),envPtr);TclEmitInt4((val2),envPtr)
 #define OP44(name,val1,val2) \
     TclEmitInstInt4(INST_##name,(val1),envPtr);TclEmitInt4((val2),envPtr)
-#define BODY(token,index) \
-    SetLineInformation((index));CompileBody(envPtr,(token),interp)
 #define PUSH(str) \
     PushStringLiteral(envPtr, str)
 #define JUMP4(name,var) \
@@ -752,6 +747,9 @@ TclSubstCompile(
     Tcl_InterpState state = NULL;
 
     TclSubstParse(interp, bytes, numBytes, flags, &parse, &state);
+    if (state != NULL) {
+	Tcl_ResetResult(interp);
+    }
 
     /*
      * Tricky point! If the first token does not result in a *guaranteed* push
@@ -997,9 +995,6 @@ TclSubstCompile(
  *	Instructions are added to envPtr to execute the "switch" command at
  *	runtime.
  *
- * FIXME:
- *	Stack depths are probably not calculated correctly.
- *
  *----------------------------------------------------------------------
  */
 
@@ -1290,13 +1285,15 @@ TclCompileSwitchCmd(
      * but it handles the most common case well enough.
      */
 
+    /* Both methods push the value to match against onto the stack. */
+    CompileWord(envPtr, valueTokenPtr, interp, valueIndex);
+
     if (mode == Switch_Exact) {
-	IssueSwitchJumpTable(interp, envPtr, mapPtr, eclIndex, valueIndex,
-		valueTokenPtr, numWords, bodyToken, bodyLines, bodyContLines);
+	IssueSwitchJumpTable(interp, envPtr, valueIndex, numWords, bodyToken,
+		bodyLines, bodyContLines);
     } else {
-	IssueSwitchChainedTests(interp, envPtr, mapPtr, eclIndex, mode,noCase,
-		valueIndex, valueTokenPtr, numWords, bodyToken, bodyLines,
-		bodyContLines);
+	IssueSwitchChainedTests(interp, envPtr, mode, noCase, valueIndex,
+		numWords, bodyToken, bodyLines, bodyContLines);
     }
     result = TCL_OK;
 
@@ -1334,13 +1331,9 @@ static void
 IssueSwitchChainedTests(
     Tcl_Interp *interp,		/* Context for compiling script bodies. */
     CompileEnv *envPtr,		/* Holds resulting instructions. */
-    ExtCmdLoc *mapPtr,		/* For mapping tokens to their source code
-				 * location. */
-    int eclIndex,
     int mode,			/* Exact, Glob or Regexp */
     int noCase,			/* Case-insensitivity flag. */
     int valueIndex,		/* The value to match against. */
-    Tcl_Token *valueTokenPtr,
     int numBodyTokens,		/* Number of tokens describing things the
 				 * switch can match against and bodies to
 				 * execute when the match succeeds. */
@@ -1365,13 +1358,6 @@ IssueSwitchChainedTests(
     int i;
 
     /*
-     * First, we push the value we're matching against on the stack.
-     */
-
-    SetLineInformation(valueIndex);
-    CompileTokens(envPtr, valueTokenPtr, interp);
-
-    /*
      * Generate a test for each arm.
      */
 
@@ -1514,7 +1500,7 @@ IssueSwitchChainedTests(
 	}
 
 	/*
-	 * Now do the actual compilation. Note that we do not use CompileBody
+	 * Now do the actual compilation. Note that we do not use BODY() 
 	 * because we may have synthesized the tokens in a non-standard
 	 * pattern.
 	 */
@@ -1596,11 +1582,7 @@ static void
 IssueSwitchJumpTable(
     Tcl_Interp *interp,		/* Context for compiling script bodies. */
     CompileEnv *envPtr,		/* Holds resulting instructions. */
-    ExtCmdLoc *mapPtr,		/* For mapping tokens to their source code
-				 * location. */
-    int eclIndex,
     int valueIndex,		/* The value to match against. */
-    Tcl_Token *valueTokenPtr,
     int numBodyTokens,		/* Number of tokens describing things the
 				 * switch can match against and bodies to
 				 * execute when the match succeeds. */
@@ -1616,13 +1598,6 @@ IssueSwitchJumpTable(
     Tcl_HashEntry *hPtr;
 
     /*
-     * First, we push the value we're matching against on the stack.
-     */
-
-    SetLineInformation(valueIndex);
-    CompileTokens(envPtr, valueTokenPtr, interp);
-
-    /*
      * Compile the switch by using a jump table, which is basically a
      * hashtable that maps from literal values to match against to the offset
      * (relative to the INST_JUMP_TABLE instruction) to jump to. The jump
@@ -2078,8 +2053,7 @@ TclCompileTryCmd(
 	 */
 
 	DefineLineInformation;	/* TIP #280 */
-	SetLineInformation(1);
-	CompileBody(envPtr, bodyToken, interp);
+	BODY(bodyToken, 1);
 	return TCL_OK;
     }
 
@@ -2874,6 +2848,7 @@ TclCompileUnsetCmd(
     Tcl_Obj *leadingWord;
     DefineLineInformation;	/* TIP #280 */
 
+    /* TODO: Consider support for compiling expanded args. */
     numWords = parsePtr->numWords-1;
     flags = 1;
     varTokenPtr = TokenAfter(parsePtr->tokenPtr);
@@ -3058,13 +3033,12 @@ TclCompileWhileCmd(
      * Compile the loop body.
      */
 
-    SetLineInformation(2);
     bodyCodeOffset = ExceptionRangeStarts(envPtr, range);
     if (!loopMayEnd) {
 	envPtr->exceptArrayPtr[range].continueOffset = testCodeOffset;
 	envPtr->exceptArrayPtr[range].codeOffset = bodyCodeOffset;
     }
-    CompileBody(envPtr, bodyTokenPtr, interp);
+    BODY(bodyTokenPtr, 2);
     ExceptionRangeEnds(envPtr, range);
     OP(		POP);
 
@@ -3230,6 +3204,7 @@ CompileAssociativeBinaryOpCmd(
     DefineLineInformation;	/* TIP #280 */
     int words;
 
+    /* TODO: Consider support for compiling expanded args. */
     for (words=1 ; words<parsePtr->numWords ; words++) {
 	tokenPtr = TokenAfter(tokenPtr);
 	CompileWord(envPtr, tokenPtr, interp, words);
@@ -3313,6 +3288,7 @@ CompileComparisonOpCmd(
     Tcl_Token *tokenPtr;
     DefineLineInformation;	/* TIP #280 */
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords < 3) {
 	PUSH("1");
     } else if (parsePtr->numWords == 3) {
@@ -3650,6 +3626,7 @@ TclCompileMinusOpCmd(
     DefineLineInformation;	/* TIP #280 */
     int words;
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords == 1) {
 	/*
 	 * Fallback to direct eval to report syntax error.
@@ -3695,6 +3672,7 @@ TclCompileDivOpCmd(
     DefineLineInformation;	/* TIP #280 */
     int words;
 
+    /* TODO: Consider support for compiling expanded args. */
     if (parsePtr->numWords == 1) {
 	/*
 	 * Fallback to direct eval to report syntax error.
diff --git a/generic/tclCompile.c b/generic/tclCompile.c
index f2da265..151bfd3 100644
--- a/generic/tclCompile.c
+++ b/generic/tclCompile.c
@@ -562,8 +562,6 @@ static void		EnterCmdExtentData(CompileEnv *envPtr,
 			    int cmdNumber, int numSrcBytes, int numCodeBytes);
 static void		EnterCmdStartData(CompileEnv *envPtr,
 			    int cmdNumber, int srcOffset, int codeOffset);
-static Command *	FindCompiledCommandFromToken(Tcl_Interp *interp,
-			    Tcl_Token *tokenPtr);
 static void		FreeByteCodeInternalRep(Tcl_Obj *objPtr);
 static void		FreeSubstCodeInternalRep(Tcl_Obj *objPtr);
 static int		GetCmdLocEncodingSize(CompileEnv *envPtr);
@@ -697,9 +695,7 @@ TclSetByteCodeFromAny(
 
     clLocPtr = TclContinuationsGet(objPtr);
     if (clLocPtr) {
-	compEnv.clLoc = clLocPtr;
-	compEnv.clNext = &compEnv.clLoc->loc[0];
-	Tcl_Preserve(compEnv.clLoc);
+	compEnv.clNext = &clLocPtr->loc[0];
     }
 
     TclCompileScript(interp, stringPtr, length, &compEnv);
@@ -726,9 +722,7 @@ TclSetByteCodeFromAny(
 	TclInitCompileEnv(interp, &compEnv, stringPtr, length,
 		iPtr->invokeCmdFramePtr, iPtr->invokeWord);
 	if (clLocPtr) {
-	    compEnv.clLoc = clLocPtr;
-	    compEnv.clNext = &compEnv.clLoc->loc[0];
-	    Tcl_Preserve(compEnv.clLoc);
+	    compEnv.clNext = &clLocPtr->loc[0];
 	}
 	compEnv.atCmdStart = 2;		/* The disabling magic. */
 	TclCompileScript(interp, stringPtr, length, &compEnv);
@@ -1274,8 +1268,6 @@ ReleaseCmdWordData(
 	ckfree((char *) eclPtr->loc);
     }
 
-    Tcl_DeleteHashTable (&eclPtr->litInfo);
-
     ckfree((char *) eclPtr);
 }
 
@@ -1360,9 +1352,8 @@ TclInitCompileEnv(
     envPtr->extCmdMapPtr->nloc = 0;
     envPtr->extCmdMapPtr->nuloc = 0;
     envPtr->extCmdMapPtr->path = NULL;
-    Tcl_InitHashTable(&envPtr->extCmdMapPtr->litInfo, TCL_ONE_WORD_KEYS);
 
-    if ((invoker == NULL) || (invoker->type == TCL_LOCATION_EVAL_LIST)) {
+    if (invoker == NULL) {
 	/*
 	 * Initialize the compiler for relative counting in case of a
 	 * dynamic context.
@@ -1476,7 +1467,6 @@ TclInitCompileEnv(
      * data is available.
      */
 
-    envPtr->clLoc = NULL;
     envPtr->clNext = NULL;
 
     envPtr->auxDataArrayPtr = envPtr->staticAuxDataArraySpace;
@@ -1561,16 +1551,6 @@ TclFreeCompileEnv(
 	ReleaseCmdWordData(envPtr->extCmdMapPtr);
 	envPtr->extCmdMapPtr = NULL;
     }
-
-    /*
-     * If we used data about invisible continuation lines, then now is the
-     * time to release on our hold on it. The lock was set in function
-     * TclSetByteCodeFromAny(), found in this file.
-     */
-
-    if (envPtr->clLoc) {
-	Tcl_Release(envPtr->clLoc);
-    }
 }
 
 /*
@@ -1654,54 +1634,6 @@ TclWordKnownAtCompileTime(
 }
 
 /*
- * ---------------------------------------------------------------------
- *
- * FindCompiledCommandFromToken --
- *
- *	A simple helper that looks up a command's compiler from its token.
- *
- * ---------------------------------------------------------------------
- */
-
-static Command *
-FindCompiledCommandFromToken(
-    Tcl_Interp *interp,
-    Tcl_Token *tokenPtr)
-{
-    Tcl_DString ds;
-    Command *cmdPtr;
-
-    /*
-     * If we have a non-trivial token or are suppressing compilation, we stop
-     * right now.
-     */
-
-    if ((tokenPtr->type != TCL_TOKEN_SIMPLE_WORD)
-	    || (((Interp *) interp)->flags & DONT_COMPILE_CMDS_INLINE)) {
-	return NULL;
-    }
-
-    /*
-     * We copy the string before trying to find the command by name. We used
-     * to modify the string in place, but this is not safe because the name
-     * resolution handlers could have side effects that rely on the unmodified
-     * string.
-     */
-
-    Tcl_DStringInit(&ds);
-    TclDStringAppendToken(&ds, &tokenPtr[1]);
-    cmdPtr = (Command *) Tcl_FindCommand(interp, Tcl_DStringValue(&ds), NULL,
-	    /*flags*/ 0);
-    if (cmdPtr != NULL && (cmdPtr->compileProc == NULL
-	    || (cmdPtr->nsPtr->flags & NS_SUPPRESS_COMPILATION)
-	    || (cmdPtr->flags & CMD_HAS_EXEC_TRACES))) {
-	cmdPtr = NULL;
-    }
-    Tcl_DStringFree(&ds);
-    return cmdPtr;
-}
-
-/*
  *----------------------------------------------------------------------
  *
  * TclCompileScript --
@@ -1719,460 +1651,460 @@ FindCompiledCommandFromToken(
  *----------------------------------------------------------------------
  */
 
-void
-TclCompileScript(
-    Tcl_Interp *interp,		/* Used for error and status reporting. Also
-				 * serves as context for finding and compiling
-				 * commands. May not be NULL. */
-    const char *script,		/* The source script to compile. */
-    int numBytes,		/* Number of bytes in script. If < 0, the
-				 * script consists of all bytes up to the
-				 * first null character. */
-    CompileEnv *envPtr)		/* Holds resulting instructions. */
+static int
+ExpandRequested(
+    Tcl_Token *tokenPtr,
+    int numWords)
 {
-    int lastTopLevelCmdIndex = -1;
-				/* Index of most recent toplevel command in
-				 * the command location table. Initialized to
-				 * avoid compiler warning. */
-    int startCodeOffset = -1;	/* Offset of first byte of current command's
-				 * code. Init. to avoid compiler warning. */
-    unsigned char *entryCodeNext = envPtr->codeNext;
-    const char *p, *next;
-    Command *cmdPtr;
-    Tcl_Token *tokenPtr;
-    int bytesLeft, isFirstCmd, wordIdx, currCmdIndex, commandLength, objIndex;
-    /* TIP #280 */
-    ExtCmdLoc *eclPtr = envPtr->extCmdMapPtr;
-    int *wlines, wlineat, cmdLine, *clNext;
-    Tcl_Parse parse, *parsePtr = &parse;
+    /* Determine whether any words of the command require expansion */
+    while (numWords--) {
+	if (tokenPtr->type == TCL_TOKEN_EXPAND_WORD) {
+	    return 1;
+	}
+	tokenPtr = TokenAfter(tokenPtr);
+    }
+    return 0;
+}
 
-    if (envPtr->iPtr == NULL) {
-	Tcl_Panic("TclCompileScript() called on uninitialized CompileEnv");
+static void
+CompileCmdLiteral(
+    Tcl_Interp *interp,
+    Tcl_Obj *cmdObj,
+    CompileEnv *envPtr)
+{
+    int numBytes;
+    const char *bytes = Tcl_GetStringFromObj(cmdObj, &numBytes);
+    int cmdLitIdx = TclRegisterNewCmdLiteral(envPtr, bytes, numBytes);
+    Command *cmdPtr = (Command *) Tcl_GetCommandFromObj(interp, cmdObj);
+
+    if (cmdPtr) {
+	TclSetCmdNameObj(interp, TclFetchLiteral(envPtr, cmdLitIdx), cmdPtr);
     }
+    TclEmitPush(cmdLitIdx, envPtr);
+}
 
-    if (numBytes < 0) {
-	numBytes = strlen(script);
+void
+TclCompileInvocation(
+    Tcl_Interp *interp,
+    Tcl_Token *tokenPtr,
+    Tcl_Obj *cmdObj,
+    int numWords,
+    CompileEnv *envPtr)
+{
+    int wordIdx = 0;
+    DefineLineInformation;
+
+    if (cmdObj) {
+	CompileCmdLiteral(interp, cmdObj, envPtr);
+	wordIdx = 1;
+	tokenPtr = TokenAfter(tokenPtr);
     }
-    Tcl_ResetResult(interp);
-    isFirstCmd = 1;
 
-    /*
-     * Each iteration through the following loop compiles the next command
-     * from the script.
-     */
+    for (; wordIdx < numWords; wordIdx++, tokenPtr = TokenAfter(tokenPtr)) {
+	int objIdx;
 
-    p = script;
-    bytesLeft = numBytes;
-    cmdLine = envPtr->line;
-    clNext = envPtr->clNext;
-    do {
-	if (Tcl_ParseCommand(interp, p, bytesLeft, 0, parsePtr) != TCL_OK) {
-	    /*
-	     * Compile bytecodes to report the parse error at runtime.
-	     */
+	SetLineInformation(wordIdx);
 
-	    Tcl_LogCommandInfo(interp, script, parsePtr->commandStart,
-		    /* Drop the command terminator (";","]") if appropriate */
-		    (parsePtr->term ==
-		    parsePtr->commandStart + parsePtr->commandSize - 1)?
-		    parsePtr->commandSize - 1 : parsePtr->commandSize);
-	    TclCompileSyntaxError(interp, envPtr);
-	    break;
+	if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+	    CompileTokens(envPtr, tokenPtr, interp);
+	    continue;
 	}
 
-	/*
-	 * TIP #280: We have to count newlines before the command even in the
-	 * degenerate case when the command has no words. (See test
-	 * info-30.33).
-	 * So make that counting here, and not in the (numWords > 0) branch
-	 * below.
-	 */
+	objIdx = TclRegisterNewLiteral(envPtr,
+		tokenPtr[1].start, tokenPtr[1].size);
+	if (envPtr->clNext) {
+	    TclContinuationsEnterDerived(TclFetchLiteral(envPtr, objIdx),
+		    tokenPtr[1].start - envPtr->source, envPtr->clNext);
+	}
+	TclEmitPush(objIdx, envPtr);
+    }
 
-	TclAdvanceLines(&cmdLine, p, parsePtr->commandStart);
-	TclAdvanceContinuations(&cmdLine, &clNext,
-		parsePtr->commandStart - envPtr->source);
+    if (wordIdx <= 255) {
+	TclEmitInstInt1(INST_INVOKE_STK1, wordIdx, envPtr);
+    } else {
+	TclEmitInstInt4(INST_INVOKE_STK4, wordIdx, envPtr);
+    }
+}
 
-	if (parsePtr->numWords > 0) {
-	    int expand = 0;	/* Set if there are dynamic expansions to
-				 * handle */
+static void
+CompileExpanded(
+    Tcl_Interp *interp,
+    Tcl_Token *tokenPtr,
+    Tcl_Obj *cmdObj,
+    int numWords,
+    CompileEnv *envPtr)
+{
+    int wordIdx = 0;
+    DefineLineInformation;
 
-	    /*
-	     * If not the first command, pop the previous command's result
-	     * and, if we're compiling a top level command, update the last
-	     * command's code size to account for the pop instruction.
-	     */
 
-	    if (!isFirstCmd) {
-		TclEmitOpcode(INST_POP, envPtr);
-		envPtr->cmdMapPtr[lastTopLevelCmdIndex].numCodeBytes =
-			(envPtr->codeNext - envPtr->codeStart)
-			- startCodeOffset;
-	    }
+    StartExpanding(envPtr);
+    if (cmdObj) {
+	CompileCmdLiteral(interp, cmdObj, envPtr);
+	wordIdx = 1;
+	tokenPtr = TokenAfter(tokenPtr);
+    }
 
-	    /*
-	     * Determine the actual length of the command.
-	     */
+    for (; wordIdx < numWords; wordIdx++, tokenPtr = TokenAfter(tokenPtr)) {
+	int objIdx;
 
-	    commandLength = parsePtr->commandSize;
-	    if (parsePtr->term == parsePtr->commandStart + commandLength-1) {
-		/*
-		 * The command terminator character (such as ; or ]) is the
-		 * last character in the parsed command. Reduce the length by
-		 * one so that the trace message doesn't include the
-		 * terminator character.
-		 */
+	SetLineInformation(wordIdx);
 
-		commandLength -= 1;
+	if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+	    CompileTokens(envPtr, tokenPtr, interp);
+	    if (tokenPtr->type == TCL_TOKEN_EXPAND_WORD) {
+		TclEmitInstInt4(INST_EXPAND_STKTOP,
+			envPtr->currStackDepth, envPtr);
 	    }
+	    continue;
+	}
 
-#ifdef TCL_COMPILE_DEBUG
-	    /*
-	     * If tracing, print a line for each top level command compiled.
-	     */
+	objIdx = TclRegisterNewLiteral(envPtr,
+		tokenPtr[1].start, tokenPtr[1].size);
+	if (envPtr->clNext) {
+	    TclContinuationsEnterDerived(TclFetchLiteral(envPtr, objIdx),
+		    tokenPtr[1].start - envPtr->source, envPtr->clNext);
+	}
+	TclEmitPush(objIdx, envPtr);
+    }
 
-	    if ((tclTraceCompile >= 1) && (envPtr->procPtr == NULL)) {
-		fprintf(stdout, "  Compiling: ");
-		TclPrintSource(stdout, parsePtr->commandStart,
-			TclMin(commandLength, 55));
-		fprintf(stdout, "\n");
-	    }
-#endif
+    /*
+     * The stack depth during argument expansion can only be
+     * managed at runtime, as the number of elements in the
+     * expanded lists is not known at compile time. We adjust here
+     * the stack depth estimate so that it is correct after the
+     * command with expanded arguments returns.
+     *
+     * The end effect of this command's invocation is that all the
+     * words of the command are popped from the stack, and the
+     * result is pushed: the stack top changes by (1-wordIdx).
+     *
+     * Note that the estimates are not correct while the command
+     * is being prepared and run, INST_EXPAND_STKTOP is not
+     * stack-neutral in general.
+     */
 
-	    /*
-	     * Check whether expansion has been requested for any of the
-	     * words.
-	     */
+    TclEmitOpcode(INST_INVOKE_EXPANDED, envPtr);
+    envPtr->expandCount--;
+    TclAdjustStackDepth(1 - wordIdx, envPtr);
+}
 
-	    for (wordIdx = 0, tokenPtr = parsePtr->tokenPtr;
-		    wordIdx < parsePtr->numWords;
-		    wordIdx++, tokenPtr += tokenPtr->numComponents + 1) {
-		if (tokenPtr->type == TCL_TOKEN_EXPAND_WORD) {
-		    expand = 1;
-		    break;
-		}
-	    }
+static int 
+CompileCmdCompileProc(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,
+    CompileEnv *envPtr)
+{
+    int unwind = 0, incrOffset = -1;
+    DefineLineInformation;
 
+    /*
+     * Emit of the INST_START_CMD instruction is controlled by
+     * the value of envPtr->atCmdStart:
+     *
+     * atCmdStart == 2	: We are not using the INST_START_CMD instruction.
+     * atCmdStart == 1	: INST_START_CMD was the last instruction emitted.
+     *			: We do not need to emit another.  Instead we
+     *			: increment the number of cmds started at it (except
+     *			: for the special case at the start of a script.)
+     * atCmdStart == 0	: The last instruction was something else.  We need
+     *			: to emit INST_START_CMD here.
+     */
+
+    switch (envPtr->atCmdStart) {
+    case 0:
+	unwind = tclInstructionTable[INST_START_CMD].numBytes;
+	TclEmitInstInt4(INST_START_CMD, 0, envPtr);
+	incrOffset = envPtr->codeNext - envPtr->codeStart;
+	TclEmitInt4(0, envPtr);
+	break;
+    case 1:
+	if (envPtr->codeNext > envPtr->codeStart) {
+	    incrOffset = envPtr->codeNext - 4 - envPtr->codeStart;
+	}
+	break;
+    case 2:
+	/* Nothing to do */
+	;
+    }
+
+    if (TCL_OK == TclAttemptCompileProc(interp, parsePtr, 1, cmdPtr, envPtr)) {
+	if (incrOffset >= 0) {
 	    /*
-	     * If expansion was requested, check if the command declares that
-	     * it knows how to compile it. Note that if expansion is requested
-	     * for the first word, this check will fail as the token type will
-	     * inhibit it. (Checked inside FindCompiledCommandFromToken.) This
-	     * is as it should be.
+	     * We successfully compiled a command.  Increment the number
+	     * of commands that start at the currently active INST_START_CMD.
 	     */
+	    unsigned char *incrPtr = envPtr->codeStart + incrOffset;
+	    unsigned char *startPtr = incrPtr - 5;
 
-	    if (expand) {
-		cmdPtr = FindCompiledCommandFromToken(interp,
-			parsePtr->tokenPtr);
-		if (cmdPtr && (cmdPtr->flags & CMD_COMPILES_EXPANDED)) {
-		    expand = 0;
-		}
+	    TclIncrUInt4AtPtr(incrPtr, 1);
+	    if (unwind) {
+		/* We started the INST_START_CMD.  Record the code length. */
+		TclStoreInt4AtPtr(envPtr->codeNext - startPtr, startPtr + 1);
 	    }
+	}
+	return TCL_OK;
+    }
 
-	    envPtr->numCommands++;
-	    currCmdIndex = envPtr->numCommands - 1;
-	    lastTopLevelCmdIndex = currCmdIndex;
-	    startCodeOffset = envPtr->codeNext - envPtr->codeStart;
-	    EnterCmdStartData(envPtr, currCmdIndex,
-		    parsePtr->commandStart - envPtr->source, startCodeOffset);
+    envPtr->codeNext -= unwind; /* Unwind INST_START_CMD */
 
-	    /*
-	     * Should only start issuing instructions after the "command has
-	     * started" so that the command range is correct in the bytecode.
-	     */
+    /*
+     * Throw out any line information generated by the failed
+     * compile attempt.
+     */
+    while (mapPtr->nuloc - 1 > eclIndex) {
+	mapPtr->nuloc--;
+	ckfree(mapPtr->loc[mapPtr->nuloc].line);
+	mapPtr->loc[mapPtr->nuloc].line = NULL;
+    }
 
-	    if (expand) {
-		StartExpanding(envPtr);
-	    }
+    /*
+     * Reset the index of next command.
+     * Toss out any from failed nested partial compiles.
+     */
+    envPtr->numCommands = mapPtr->nuloc;
 
-	    /*
-	     * TIP #280. Scan the words and compute the extended location
-	     * information. The map first contain full per-word line
-	     * information for use by the compiler. This is later replaced by
-	     * a reduced form which signals non-literal words, stored in
-	     * 'wlines'.
-	     */
+    return TCL_ERROR;
+}
 
-	    EnterCmdWordData(eclPtr, parsePtr->commandStart - envPtr->source,
-		    parsePtr->tokenPtr, parsePtr->commandStart,
-		    parsePtr->commandSize, parsePtr->numWords, cmdLine,
-		    clNext, &wlines, envPtr);
-	    wlineat = eclPtr->nuloc - 1;
+static int
+CompileCommandTokens(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    CompileEnv *envPtr)
+{
+    Interp *iPtr = (Interp *) interp;
+    Tcl_Token *tokenPtr = parsePtr->tokenPtr;
+    ExtCmdLoc *eclPtr = envPtr->extCmdMapPtr;
+    Tcl_Obj *cmdObj = Tcl_NewObj();
+    Command *cmdPtr = NULL;
+    int code = TCL_ERROR;
+    int cmdKnown, expand = -1;
+    int *wlines, wlineat;
+    int cmdLine = envPtr->line;
+    int *clNext = envPtr->clNext;
+    int cmdIdx = envPtr->numCommands;
+    int startCodeOffset = envPtr->codeNext - envPtr->codeStart;
 
-	    /*
-	     * Each iteration of the following loop compiles one word from the
-	     * command.
-	     */
+    assert (parsePtr->numWords > 0);
 
-	    for (wordIdx = 0, tokenPtr = parsePtr->tokenPtr;
-		    wordIdx < parsePtr->numWords; wordIdx++,
-		    tokenPtr += tokenPtr->numComponents + 1) {
-		/*
-		 * Note the parse location information.
-		 */
+    /* Pre-Compile */
 
-		envPtr->line = eclPtr->loc[wlineat].line[wordIdx];
-		envPtr->clNext = eclPtr->loc[wlineat].next[wordIdx];
+    envPtr->numCommands++;
+    EnterCmdStartData(envPtr, cmdIdx,
+	    parsePtr->commandStart - envPtr->source, startCodeOffset);
 
-		if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
-		    /*
-		     * The word is not a simple string of characters.
-		     */
+    /*
+     * TIP #280. Scan the words and compute the extended location
+     * information. The map first contain full per-word line
+     * information for use by the compiler. This is later replaced by
+     * a reduced form which signals non-literal words, stored in
+     * 'wlines'.
+     */
 
-		    CompileTokens(envPtr, tokenPtr, interp);
-		    if (expand && tokenPtr->type == TCL_TOKEN_EXPAND_WORD) {
-			TclEmitInstInt4(INST_EXPAND_STKTOP,
-				envPtr->currStackDepth, envPtr);
-		    }
-		    continue;
-		}
+    EnterCmdWordData(eclPtr, parsePtr->commandStart - envPtr->source,
+	    parsePtr->tokenPtr, parsePtr->commandStart,
+	    parsePtr->commandSize, parsePtr->numWords, cmdLine,
+	    clNext, &wlines, envPtr);
+    wlineat = eclPtr->nuloc - 1;
 
-		/*
-		 * This is a simple string of literal characters (i.e. we know
-		 * it absolutely and can use it directly). If this is the
-		 * first word and the command has a compile procedure, let it
-		 * compile the command.
-		 */
+    envPtr->line = eclPtr->loc[wlineat].line[0];
+    envPtr->clNext = eclPtr->loc[wlineat].next[0];
 
-		if ((wordIdx == 0) && !expand) {
-		    cmdPtr = FindCompiledCommandFromToken(interp, tokenPtr);
-		    if (cmdPtr) {
-			int savedNumCmds = envPtr->numCommands;
-			unsigned savedCodeNext =
-				envPtr->codeNext - envPtr->codeStart;
-			int update = 0;
-			int startStackDepth = envPtr->currStackDepth;
-
-			/*
-			 * Mark the start of the command; the proper bytecode
-			 * length will be updated later. There is no need to
-			 * do this for the first bytecode in the compile env,
-			 * as the check is done before calling
-			 * TclNRExecuteByteCode(). Do emit an INST_START_CMD
-			 * in special cases where the first bytecode is in a
-			 * loop, to insure that the corresponding command is
-			 * counted properly. Compilers for commands able to
-			 * produce such a beast (currently 'while 1' only) set
-			 * envPtr->atCmdStart to 0 in order to signal this
-			 * case. [Bug 1752146]
-			 *
-			 * Note that the environment is initialised with
-			 * atCmdStart=1 to avoid emitting ISC for the first
-			 * command.
-			 */
-
-			if (envPtr->atCmdStart == 1) {
-			    if (savedCodeNext != 0) {
-				/*
-				 * Increase the number of commands being
-				 * started at the current point. Note that
-				 * this depends on the exact layout of the
-				 * INST_START_CMD's operands, so be careful!
-				 */
-
-				TclIncrUInt4AtPtr(envPtr->codeNext - 4, 1)
-			    }
-			} else if (envPtr->atCmdStart == 0) {
-			    TclEmitInstInt4(INST_START_CMD, 0, envPtr);
-			    TclEmitInt4(1, envPtr);
-			    update = 1;
-			}
-
-			if (cmdPtr->compileProc(interp, parsePtr, cmdPtr,
-				envPtr) == TCL_OK) {
-			    /*
-			     * Confirm that the command compiler generated a
-			     * single value on the stack as its result. This
-			     * is only done in debugging mode, as it *should*
-			     * be correct and normal users have no reasonable
-			     * way to fix it anyway.
-			     */
+    /* Do we know the command word? */
+    Tcl_IncrRefCount(cmdObj);
+    tokenPtr = parsePtr->tokenPtr;
+    cmdKnown = TclWordKnownAtCompileTime(tokenPtr, cmdObj);
 
-#ifdef TCL_COMPILE_DEBUG
-			    int diff = envPtr->currStackDepth-startStackDepth;
-
-			    if (diff != 1) {
-				Tcl_Panic("bad stack adjustment when compiling"
-					" %.*s (was %d instead of 1)",
-					parsePtr->tokenPtr->size,
-					parsePtr->tokenPtr->start, diff);
-			    }
-#endif
-			    if (update) {
-				/*
-				 * Fix the bytecode length.
-				 */
-
-				unsigned char *fixPtr = envPtr->codeStart
-					+ savedCodeNext + 1;
-				unsigned fixLen = envPtr->codeNext
-					- envPtr->codeStart - savedCodeNext;
-
-				TclStoreInt4AtPtr(fixLen, fixPtr);
-			    }
-			    goto finishCommand;
-			}
-
-			if (envPtr->atCmdStart == 1 && savedCodeNext != 0) {
-			    /*
-			     * Decrease the number of commands being started
-			     * at the current point. Note that this depends on
-			     * the exact layout of the INST_START_CMD's
-			     * operands, so be careful!
-			     */
-
-			    TclIncrUInt4AtPtr(envPtr->codeNext - 4, -1);
-			}
-
-			/*
-			 * Restore numCommands and codeNext to their correct
-			 * values, removing any commands compiled before the
-			 * failure to produce bytecode got reported. [Bugs
-			 * 705406 and 735055]
-			 */
-
-			envPtr->numCommands = savedNumCmds;
-			envPtr->codeNext = envPtr->codeStart + savedCodeNext;
-
-			/*
-			 * And the stack depth too!!  [Bug 3614102].
-			 */
-
-			envPtr->currStackDepth = startStackDepth;
-		    }
+    /* Is this a command we should (try to) compile with a compileProc ? */
+    if (cmdKnown && !(iPtr->flags & DONT_COMPILE_CMDS_INLINE)) {
+	cmdPtr = (Command *) Tcl_GetCommandFromObj(interp, cmdObj);
+	if (cmdPtr) {
+	    /*
+	     * Found a command.  Test the ways we can be told
+	     * not to attempt to compile it.
+	     */
+	    if ((cmdPtr->compileProc == NULL)
+		    || (cmdPtr->nsPtr->flags & NS_SUPPRESS_COMPILATION)
+		    || (cmdPtr->flags & CMD_HAS_EXEC_TRACES)) {
+		cmdPtr = NULL;
+	    }
+	}
+	if (cmdPtr && !(cmdPtr->flags & CMD_COMPILES_EXPANDED)) {
+	    expand = ExpandRequested(parsePtr->tokenPtr, parsePtr->numWords);
+	    if (expand) {
+		/* We need to expand, but compileProc cannot. */
+		cmdPtr = NULL;
+	    }
+	}
+    }
 
-		    /*
-		     * No compile procedure so push the word. If the command
-		     * was found, push a CmdName object to reduce runtime
-		     * lookups. Mark this as a command name literal to reduce
-		     * shimmering. 
-		     */
+    /* If cmdPtr != NULL, we will try to call cmdPtr->compileProc */
+    if (cmdPtr) {
+	code = CompileCmdCompileProc(interp, parsePtr, cmdPtr, envPtr);
+    }
 
-		    objIndex = TclRegisterNewCmdLiteral(envPtr,
-			    tokenPtr[1].start, tokenPtr[1].size);
-		    if (cmdPtr) {
-			TclSetCmdNameObj(interp,
-				TclFetchLiteral(envPtr, objIndex), cmdPtr);
-		    }
-		} else {
-		    /*
-		     * Simple argument word of a command. We reach this if and
-		     * only if the command word was not compiled for whatever
-		     * reason. Register the literal's location for use by
-		     * uplevel, etc. commands, should they encounter it
-		     * unmodified. We care only if the we are in a context
-		     * which already allows absolute counting.
-		     */
+    if (code == TCL_ERROR) {
+	if (expand < 0) {
+	    expand = ExpandRequested(parsePtr->tokenPtr, parsePtr->numWords);
+	}
 
-		    objIndex = TclRegisterNewLiteral(envPtr,
-			    tokenPtr[1].start, tokenPtr[1].size);
+	if (expand) {
+	    CompileExpanded(interp, parsePtr->tokenPtr,
+		    cmdKnown ? cmdObj : NULL, parsePtr->numWords, envPtr);
+	} else {
+	    TclCompileInvocation(interp, parsePtr->tokenPtr,
+		    cmdKnown ? cmdObj : NULL, parsePtr->numWords, envPtr);
+	}
+    }
 
-		    if (envPtr->clNext) {
-			TclContinuationsEnterDerived(
-				TclFetchLiteral(envPtr, objIndex),
-				tokenPtr[1].start - envPtr->source,
-				eclPtr->loc[wlineat].next[wordIdx]);
-		    }
-		}
-		TclEmitPush(objIndex, envPtr);
-	    } /* for loop */
+    Tcl_DecrRefCount(cmdObj);
 
-	    /*
-	     * Emit an invoke instruction for the command. We skip this if a
-	     * compile procedure was found for the command.
-	     */
-	    assert(wordIdx > 0);
+    TclEmitOpcode(INST_POP, envPtr);
+    EnterCmdExtentData(envPtr, cmdIdx,
+	    parsePtr->term - parsePtr->commandStart,
+	    (envPtr->codeNext-envPtr->codeStart) - startCodeOffset);
 
-	    if (expand) {
-		/*
-		 * The stack depth during argument expansion can only be
-		 * managed at runtime, as the number of elements in the
-		 * expanded lists is not known at compile time. We adjust here
-		 * the stack depth estimate so that it is correct after the
-		 * command with expanded arguments returns.
-		 *
-		 * The end effect of this command's invocation is that all the
-		 * words of the command are popped from the stack, and the
-		 * result is pushed: the stack top changes by (1-wordIdx).
-		 *
-		 * Note that the estimates are not correct while the command
-		 * is being prepared and run, INST_EXPAND_STKTOP is not
-		 * stack-neutral in general.
-		 */
+    /*
+     * TIP #280: Free full form of per-word line data and insert the
+     * reduced form now
+     */
 
-		TclEmitOpcode(INST_INVOKE_EXPANDED, envPtr);
-		envPtr->expandCount--;
-		TclAdjustStackDepth(1 - wordIdx, envPtr);
-	    } else {
-		/*
-		 * Save PC -> command map for the TclArgumentBC* functions.
-		 */
+    envPtr->line = cmdLine;
+    envPtr->clNext = clNext;
+    ckfree(eclPtr->loc[wlineat].line);
+    ckfree(eclPtr->loc[wlineat].next);
+    eclPtr->loc[wlineat].line = wlines;
+    eclPtr->loc[wlineat].next = NULL;
 
-		int isnew;
-		Tcl_HashEntry *hePtr = Tcl_CreateHashEntry(&eclPtr->litInfo,
-			INT2PTR(envPtr->codeNext - envPtr->codeStart),
-			&isnew);
+    return cmdIdx;
+}
 
-		Tcl_SetHashValue(hePtr, INT2PTR(wlineat));
-		if (wordIdx <= 255) {
-		    TclEmitInstInt1(INST_INVOKE_STK1, wordIdx, envPtr);
-		} else {
-		    TclEmitInstInt4(INST_INVOKE_STK4, wordIdx, envPtr);
-		}
-	    }
+void
+TclCompileScript(
+    Tcl_Interp *interp,		/* Used for error and status reporting. Also
+				 * serves as context for finding and compiling
+				 * commands. May not be NULL. */
+    const char *script,		/* The source script to compile. */
+    int numBytes,		/* Number of bytes in script. If < 0, the
+				 * script consists of all bytes up to the
+				 * first null character. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    int lastCmdIdx = -1;	/* Index into envPtr->cmdMapPtr of the last
+				 * command this routine compiles into bytecode.
+				 * Initial value of -1 indicates this routine
+				 * has not yet generated any bytecode. */
+    const char *p = script;	/* Where we are in our compile. */
 
-	    /*
-	     * Update the compilation environment structure and record the
-	     * offsets of the source and code for the command.
-	     */
+    if (envPtr->iPtr == NULL) {
+	Tcl_Panic("TclCompileScript() called on uninitialized CompileEnv");
+    }
 
-	finishCommand:
-	    EnterCmdExtentData(envPtr, currCmdIndex, commandLength,
-		    (envPtr->codeNext-envPtr->codeStart) - startCodeOffset);
-	    isFirstCmd = 0;
+    /* Each iteration compiles one command from the script. */
 
+    while (numBytes > 0) {
+	Tcl_Parse parse;
+	const char *next;
+
+	if (TCL_OK != Tcl_ParseCommand(interp, p, numBytes, 0, &parse)) {
 	    /*
-	     * TIP #280: Free full form of per-word line data and insert the
-	     * reduced form now
+	     * Compile bytecodes to report the parse error at runtime.
 	     */
 
-	    ckfree(eclPtr->loc[wlineat].line);
-	    ckfree(eclPtr->loc[wlineat].next);
-	    eclPtr->loc[wlineat].line = wlines;
-	    eclPtr->loc[wlineat].next = NULL;
-	} /* end if parsePtr->numWords > 0 */
+	    Tcl_LogCommandInfo(interp, script, parse.commandStart,
+		    parse.term + 1 - parse.commandStart);
+	    TclCompileSyntaxError(interp, envPtr);
+	    return;
+	}
 
+#ifdef TCL_COMPILE_DEBUG
 	/*
-	 * Advance to the next command in the script.
+	 * If tracing, print a line for each top level command compiled.
+	 * TODO: Suppress when numWords == 0 ?
 	 */
 
-	next = parsePtr->commandStart + parsePtr->commandSize;
-	bytesLeft -= next - p;
-	p = next;
+	if ((tclTraceCompile >= 1) && (envPtr->procPtr == NULL)) {
+	    int commandLength = parse.term - parse.commandStart;
+	    fprintf(stdout, "  Compiling: ");
+	    TclPrintSource(stdout, parse.commandStart,
+		    TclMin(commandLength, 55));
+	    fprintf(stdout, "\n");
+	}
+#endif
 
 	/*
-	 * TIP #280: Track lines in the just compiled command.
+	 * TIP #280: Count newlines before the command start.
+	 * (See test info-30.33).
 	 */
 
-	TclAdvanceLines(&cmdLine, parsePtr->commandStart, p);
-	TclAdvanceContinuations(&cmdLine, &clNext, p - envPtr->source);
-	Tcl_FreeParse(parsePtr);
-    } while (bytesLeft > 0);
+	TclAdvanceLines(&envPtr->line, p, parse.commandStart);
+	TclAdvanceContinuations(&envPtr->line, &envPtr->clNext,
+		parse.commandStart - envPtr->source);
 
-    /*
-     * TIP #280: Bring the line counts in the CompEnv up to date.
-     *	See tests info-30.33,34,35 .
-     */
+	/*
+	 * Advance parser to the next command in the script.
+	 */
 
-    envPtr->line = cmdLine;
-    envPtr->clNext = clNext;
+	next = parse.commandStart + parse.commandSize;
+	numBytes -= next - p;
+	p = next;
 
-    /*
-     * If the source script yielded no instructions (e.g., if it was empty),
-     * push an empty string as the command's result.
-     */
+	if (parse.numWords == 0) {
+	    /*
+	     * The "command" parsed has no words.  In this case
+	     * we can skip the rest of the loop body.  With no words,
+	     * clearly CompileCommandTokens() has nothing to do.  Since
+	     * the parser aggressively sucks up leading comment and white
+	     * space, including newlines, parse.commandStart must be 
+	     * pointing at either the end of script, or a command-terminating
+	     * semi-colon.  In either case, the TclAdvance*() calls have
+	     * nothing to do.  Finally, when no words are parsed, no
+	     * tokens have been allocated at parse.tokenPtr so there's
+	     * also nothing for Tcl_FreeParse() to do.
+	     *
+	     * The advantage of this shortcut is that CompileCommandTokens()
+	     * can be written with an assumption that parse.numWords > 0,
+	     * with the implication the CCT() always generates bytecode.
+	     */
+	    continue;
+	}
 
-    if (envPtr->codeNext == entryCodeNext) {
+	lastCmdIdx = CompileCommandTokens(interp, &parse, envPtr);
+
+	/*
+	 * TIP #280: Track lines in the just compiled command.
+	 */
+
+	TclAdvanceLines(&envPtr->line, parse.commandStart, p);
+	TclAdvanceContinuations(&envPtr->line, &envPtr->clNext,
+		p - envPtr->source);
+	Tcl_FreeParse(&parse);
+    }
+
+    if (lastCmdIdx == -1) {
+	/*
+	 * Compiling the script yielded no bytecode.  The script must be
+	 * all whitespace, comments, and empty commands.  Such scripts
+	 * are defined to successfully produce the empty string result,
+	 * so we emit the simple bytecode that makes that happen.
+	 */
 	PushStringLiteral(envPtr, "");
+    } else {
+	/*
+	 * We compiled at least one command to bytecode.  The routine
+	 * CompileCommandTokens() follows the bytecode of each compiled
+	 * command with an INST_POP, so that stack balance is maintained
+	 * when several commands are in sequence.  (The result of each
+	 * command is thrown away before moving on to the next command).
+	 * For the last command compiled, we need to undo that INST_POP
+	 * so that the result of the last command becomes the result of
+	 * the script.  The code here removes that trailing INST_POP.
+	 */
+	envPtr->cmdMapPtr[lastCmdIdx].numCodeBytes--;
+	envPtr->codeNext--;
+	envPtr->currStackDepth++;
     }
 }
 
@@ -3944,69 +3876,6 @@ TclFixupForwardJump(
 	}
     }
 
-    /*
-     * TIP #280: Adjust the mapping from PC values to the per-command
-     * information about arguments and their line numbers.
-     *
-     * Note: We cannot simply remove an out-of-date entry and then reinsert
-     * with the proper PC, because then we might overwrite another entry which
-     * was at that location. Therefore we pull (copy + delete) all effected
-     * entries (beyond the fixed PC) into an array, update them there, and at
-     * last reinsert them all.
-     */
-
-    {
-	ExtCmdLoc* eclPtr = envPtr->extCmdMapPtr;
-
-	/* A helper structure */
-
-	typedef struct {
-	    int pc;
-	    int cmd;
-	} MAP;
-
-	/*
-	 * And the helper array. At most the whole hashtable is placed into
-	 * this.
-	 */
-
-	MAP *map = (MAP*) ckalloc (sizeof(MAP) * eclPtr->litInfo.numEntries);
-
-	Tcl_HashSearch hSearch;
-	Tcl_HashEntry* hPtr;
-	int n, k, isnew;
-
-	/*
-	 * Phase I: Locate the affected entries, and save them in adjusted
-	 * form to the array. This removes them from the hash.
-	 */
-
-	for (n = 0, hPtr = Tcl_FirstHashEntry(&eclPtr->litInfo, &hSearch);
-	     hPtr != NULL;
-	     hPtr = Tcl_NextHashEntry(&hSearch)) {
-
-	    map [n].cmd = PTR2INT(Tcl_GetHashValue(hPtr));
-	    map [n].pc  = PTR2INT(Tcl_GetHashKey (&eclPtr->litInfo,hPtr));
-
-	    if (map[n].pc >= (jumpFixupPtr->codeOffset + 2)) {
-		Tcl_DeleteHashEntry(hPtr);
-		map [n].pc += 3;
-		n++;
-	    }
-	}
-
-	/*
-	 * Phase II: Re-insert the modified entries into the hash.
-	 */
-
-	for (k=0;k<n;k++) {
-	    hPtr = Tcl_CreateHashEntry(&eclPtr->litInfo, INT2PTR(map[k].pc), &isnew);
-	    Tcl_SetHashValue(hPtr, INT2PTR(map[k].cmd));
-	}
-
-	ckfree (map);
-    }
-
     return 1;			/* the jump was grown */
 }
 
diff --git a/generic/tclCompile.h b/generic/tclCompile.h
index 1f42b05..03188df 100644
--- a/generic/tclCompile.h
+++ b/generic/tclCompile.h
@@ -200,13 +200,6 @@ typedef struct ExtCmdLoc {
     ECL *loc;			/* Command word locations (lines). */
     int nloc;			/* Number of allocated entries in 'loc'. */
     int nuloc;			/* Number of used entries in 'loc'. */
-    Tcl_HashTable litInfo;	/* Indexed by bytecode 'PC', to have the
-				 * information accessible per command and
-				 * argument, not per whole bytecode. Value is
-				 * index of command in 'loc', giving us the
-				 * literals to associate with line information
-				 * as command argument, see
-				 * TclArgumentBCEnter() */
 } ExtCmdLoc;
 
 /*
@@ -389,10 +382,6 @@ typedef struct CompileEnv {
 				 * encountered that have not yet been paired
 				 * with a corresponding
 				 * INST_INVOKE_EXPANDED. */
-    ContLineLoc *clLoc;		/* If not NULL, the table holding the
-				 * locations of the invisible continuation
-				 * lines in the input script, to adjust the
-				 * line counter. */
     int *clNext;		/* If not NULL, it refers to the next slot in
 				 * clLoc to check for an invisible
 				 * continuation line. */
@@ -1014,6 +1003,9 @@ MODULE_SCOPE ByteCode *	TclCompileObj(Tcl_Interp *interp, Tcl_Obj *objPtr,
  *----------------------------------------------------------------
  */
 
+MODULE_SCOPE int	TclAttemptCompileProc(Tcl_Interp *interp,
+			    Tcl_Parse *parsePtr, int depth, Command *cmdPtr,
+			    CompileEnv *envPtr);
 MODULE_SCOPE void	TclCleanupByteCode(ByteCode *codePtr);
 MODULE_SCOPE void	TclCleanupStackForBreakContinue(CompileEnv *envPtr,
 			    ExceptionAux *auxPtr);
@@ -1025,6 +1017,9 @@ MODULE_SCOPE void	TclCompileExpr(Tcl_Interp *interp, const char *script,
 MODULE_SCOPE void	TclCompileExprWords(Tcl_Interp *interp,
 			    Tcl_Token *tokenPtr, int numWords,
 			    CompileEnv *envPtr);
+MODULE_SCOPE void	TclCompileInvocation(Tcl_Interp *interp,
+			    Tcl_Token *tokenPtr, Tcl_Obj *cmdObj, int numWords,
+			    CompileEnv *envPtr);
 MODULE_SCOPE void	TclCompileScript(Tcl_Interp *interp,
 			    const char *script, int numBytes,
 			    CompileEnv *envPtr);
@@ -1097,7 +1092,7 @@ MODULE_SCOPE void	TclPrintSource(FILE *outFile,
 MODULE_SCOPE void	TclPushVarName(Tcl_Interp *interp,
 			    Tcl_Token *varTokenPtr, CompileEnv *envPtr,
 			    int flags, int *localIndexPtr,
-			    int *isScalarPtr, int line, int *clNext);
+			    int *isScalarPtr);
 MODULE_SCOPE int	TclRegisterLiteral(CompileEnv *envPtr,
 			    char *bytes, int length, int flags);
 MODULE_SCOPE void	TclReleaseLiteral(Tcl_Interp *interp, Tcl_Obj *objPtr);
@@ -1140,6 +1135,15 @@ MODULE_SCOPE int	TclPushProcCallFrame(ClientData clientData,
  *----------------------------------------------------------------
  */
 
+/*
+ * Simplified form to access AuxData.
+ *
+ * ClientData TclFetchAuxData(CompileEng *envPtr, int index);
+ */
+
+#define TclFetchAuxData(envPtr, index) \
+    (envPtr)->auxDataArrayPtr[(index)].clientData
+
 #define LITERAL_ON_HEAP		0x01
 #define LITERAL_CMD_NAME	0x02
 
@@ -1433,16 +1437,16 @@ MODULE_SCOPE int	TclPushProcCallFrame(ClientData clientData,
 #define TclMax(i, j)	((((int) i) > ((int) j))? (i) : (j))
 
 /*
- * Convenience macro for use when compiling bodies of commands. The ANSI C
- * "prototype" for this macro is:
+ * Convenience macros for use when compiling bodies of commands. The ANSI C
+ * "prototype" for these macros are:
  *
- * static void		CompileBody(CompileEnv *envPtr, Tcl_Token *tokenPtr,
- *			    Tcl_Interp *interp);
+ * static void		BODY(Tcl_Token *tokenPtr, int word);
  */
 
-#define CompileBody(envPtr, tokenPtr, interp) \
-    TclCompileCmdWord((interp), (tokenPtr)+1, (tokenPtr)->numComponents, \
-	    (envPtr))
+#define BODY(tokenPtr, word)						\
+    SetLineInformation((word));						\
+    TclCompileCmdWord(interp, (tokenPtr)+1, (tokenPtr)->numComponents,	\
+	    envPtr)
 
 /*
  * Convenience macro for use when compiling tokens to be pushed. The ANSI C
@@ -1541,13 +1545,10 @@ MODULE_SCOPE int	TclPushProcCallFrame(ClientData clientData,
 
 #define CompileWord(envPtr, tokenPtr, interp, word) \
     if ((tokenPtr)->type == TCL_TOKEN_SIMPLE_WORD) {			\
-	TclEmitPush(TclRegisterNewLiteral((envPtr), (tokenPtr)[1].start, \
-		(tokenPtr)[1].size), (envPtr));				\
+	PushLiteral((envPtr), (tokenPtr)[1].start, (tokenPtr)[1].size);	\
     } else {								\
-	envPtr->line = mapPtr->loc[eclIndex].line[word];		\
-	envPtr->clNext = mapPtr->loc[eclIndex].next[word];		\
-	TclCompileTokens((interp), (tokenPtr)+1, (tokenPtr)->numComponents, \
-		(envPtr));						\
+	SetLineInformation((word));					\
+	CompileTokens((envPtr), (tokenPtr), (interp));			\
     }
 
 /*
@@ -1568,9 +1569,8 @@ MODULE_SCOPE int	TclPushProcCallFrame(ClientData clientData,
     envPtr->clNext = mapPtr->loc[eclIndex].next[(word)]
 
 #define PushVarNameWord(i,v,e,f,l,sc,word) \
-    TclPushVarName(i,v,e,f,l,sc,						\
-	    mapPtr->loc[eclIndex].line[(word)],				\
-	    mapPtr->loc[eclIndex].next[(word)])
+    SetLineInformation(word);						\
+    TclPushVarName(i,v,e,f,l,sc)					
 
 /*
  * Often want to issue one of two versions of an instruction based on whether
diff --git a/generic/tclEnsemble.c b/generic/tclEnsemble.c
index 813e056..ad11785 100644
--- a/generic/tclEnsemble.c
+++ b/generic/tclEnsemble.c
@@ -35,9 +35,6 @@ static void		MakeCachedEnsembleCommand(Tcl_Obj *objPtr,
 static void		FreeEnsembleCmdRep(Tcl_Obj *objPtr);
 static void		DupEnsembleCmdRep(Tcl_Obj *objPtr, Tcl_Obj *copyPtr);
 static void		StringOfEnsembleCmdRep(Tcl_Obj *objPtr);
-static int		CompileToCompiledCommand(Tcl_Interp *interp,
-			    Tcl_Parse *parsePtr, int depth, Command *cmdPtr,
-			    CompileEnv *envPtr);
 static void		CompileToInvokedCommand(Tcl_Interp *interp,
 			    Tcl_Parse *parsePtr, Tcl_Obj *replacements,
 			    Command *cmdPtr, CompileEnv *envPtr);
@@ -88,16 +85,6 @@ const Tcl_ObjType tclEnsembleCmdType = {
     NULL			/* setFromAnyProc */
 };
 
-/*
- * Copied from tclCompCmds.c
- */
-
-#define DefineLineInformation \
-    ExtCmdLoc *mapPtr = envPtr->extCmdMapPtr;				\
-    int eclIndex = mapPtr->nuloc - 1
-#define SetLineInformation(word) \
-    envPtr->line = mapPtr->loc[eclIndex].line[(word)];			\
-    envPtr->clNext = mapPtr->loc[eclIndex].next[(word)]
 
 static inline Tcl_Obj *
 NewNsObj(
@@ -1537,6 +1524,14 @@ TclMakeEnsemble(
 	    cmdName = nameParts[nameCount - 1];
 	}
     }
+
+    /*
+     * Switch on compilation always for core ensembles now that we can do
+     * nice bytecode things with them.  Do it now.  Waiting until later will
+     * just cause pointless epoch bumps.
+     */
+
+    ensembleFlags |= ENSEMBLE_COMPILE;
     ensemble = Tcl_CreateEnsemble(interp, cmdName, ns, ensembleFlags);
 
     /*
@@ -1588,14 +1583,6 @@ TclMakeEnsemble(
 	    }
 	}
 	Tcl_SetEnsembleMappingDict(interp, ensemble, mapDict);
-
-	/*
-	 * Switch on compilation always for core ensembles now that we can do
-	 * nice bytecode things with them.
-	 */
-
-	Tcl_SetEnsembleFlags(interp, ensemble,
-		ensembleFlags | ENSEMBLE_COMPILE);
     }
 
     Tcl_DStringFree(&buf);
@@ -3004,8 +2991,8 @@ TclCompileEnsemble(
      */
 
     invokeAnyway = 1;
-    if (CompileToCompiledCommand(interp, parsePtr, depth, cmdPtr,
-	    envPtr) == TCL_OK) {
+    if (TCL_OK == TclAttemptCompileProc(interp, parsePtr, depth, cmdPtr,
+	    envPtr)) {
 	ourResult = TCL_OK;
 	goto cleanup;
     }
@@ -3039,95 +3026,88 @@ TclCompileEnsemble(
     return ourResult;
 }
 
-/*
- * How to compile a subcommand using its own command compiler. To do that, we
- * have to perform some trickery to rewrite the arguments, as compilers *must*
- * have parse tokens that refer to addresses in the original script.
- */
-
-static int
-CompileToCompiledCommand(
+int
+TclAttemptCompileProc(
     Tcl_Interp *interp,
     Tcl_Parse *parsePtr,
     int depth,
     Command *cmdPtr,
     CompileEnv *envPtr)		/* Holds resulting instructions. */
 {
-    Tcl_Parse synthetic;
-    Tcl_Token *tokenPtr;
     int result, i;
-    int savedNumCmds = envPtr->numCommands;
+    Tcl_Token *saveTokenPtr = parsePtr->tokenPtr;
     int savedStackDepth = envPtr->currStackDepth;
     unsigned savedCodeNext = envPtr->codeNext - envPtr->codeStart;
+    DefineLineInformation;
 
     if (cmdPtr->compileProc == NULL) {
 	return TCL_ERROR;
     }
 
-    TclParseInit(interp, NULL, 0, &synthetic);
-    synthetic.numWords = parsePtr->numWords - depth + 1;
-    TclGrowParseTokenArray(&synthetic, 2);
-    synthetic.numTokens = 2;
-
     /*
-     * Now we have the space to work in, install something rewritten. The
-     * first word will "officially" be the bytes of the structured ensemble
-     * name. That's technically wrong, but nobody will care; we just need
-     * *something* here...
+     * Advance parsePtr->tokenPtr so that it points at the last subcommand.
+     * This will be wrong, but it will not matter, and it will put the
+     * tokens for the arguments in the right place without the needed to
+     * allocate a synthetic Tcl_Parse struct, or copy tokens around.
      */
 
-    synthetic.tokenPtr[0].type = TCL_TOKEN_SIMPLE_WORD;
-    synthetic.tokenPtr[0].start = parsePtr->tokenPtr[0].start;
-    synthetic.tokenPtr[0].numComponents = 1;
-    synthetic.tokenPtr[1].type = TCL_TOKEN_TEXT;
-    synthetic.tokenPtr[1].start = parsePtr->tokenPtr[0].start;
-    synthetic.tokenPtr[1].numComponents = 0;
-    for (i=0,tokenPtr=parsePtr->tokenPtr ; i<depth ; i++) {
-	int sclen = (tokenPtr->start - synthetic.tokenPtr[0].start)
-		+ tokenPtr->size;
-
-	synthetic.tokenPtr[0].size = sclen;
-	synthetic.tokenPtr[1].size = sclen;
-	tokenPtr = TokenAfter(tokenPtr);
+    for (i = 0; i < depth - 1; i++) {
+	parsePtr->tokenPtr = TokenAfter(parsePtr->tokenPtr);
     }
+    parsePtr->numWords -= (depth - 1);
 
     /*
-     * Copy over the real argument tokens.
+     * Shift the line information arrays to account for different word
+     * index values.
      */
 
-    for (i=1; i<synthetic.numWords; i++) {
-	int toCopy;
-
-	toCopy = tokenPtr->numComponents + 1;
-	TclGrowParseTokenArray(&synthetic, toCopy);
-	memcpy(synthetic.tokenPtr + synthetic.numTokens, tokenPtr,
-		sizeof(Tcl_Token) * toCopy);
-	synthetic.numTokens += toCopy;
-	tokenPtr = TokenAfter(tokenPtr);
-    }
+    mapPtr->loc[eclIndex].line += (depth - 1);
+    mapPtr->loc[eclIndex].next += (depth - 1);
 
     /*
      * Hand off compilation to the subcommand compiler. At last!
      */
 
-    result = cmdPtr->compileProc(interp, &synthetic, cmdPtr, envPtr);
+    result = cmdPtr->compileProc(interp, parsePtr, cmdPtr, envPtr);
 
     /*
-     * If our target fails to compile, revert the number of commands and the
-     * pointer to the place to issue the next instruction. [Bug 3600328]
+     * Undo the shift. 
+     */
+
+    mapPtr->loc[eclIndex].line -= (depth - 1);
+    mapPtr->loc[eclIndex].next -= (depth - 1);
+
+    parsePtr->numWords += (depth - 1);
+    parsePtr->tokenPtr = saveTokenPtr;
+
+    /*
+     * If our target failed to compile, revert any data from failed partial
+     * compiles.  Note that envPtr->numCommands need not be checked because
+     * we avoid compiling subcommands that recursively call TclCompileScript().
      */
 
     if (result != TCL_OK) {
-	envPtr->numCommands = savedNumCmds;
 	envPtr->currStackDepth = savedStackDepth;
 	envPtr->codeNext = envPtr->codeStart + savedCodeNext;
-    }
+#ifdef TCL_COMPILE_DEBUG
+    } else {
+	/*
+	 * Confirm that the command compiler generated a single value on
+	 * the stack as its result. This is only done in debugging mode,
+	 * as it *should* be correct and normal users have no reasonable
+	 * way to fix it anyway.
+	 */
 
-    /*
-     * Clean up if necessary.
-     */
+	int diff = envPtr->currStackDepth - savedStackDepth;
+
+	if (diff != 1) {
+	    Tcl_Panic("bad stack adjustment when compiling"
+		    " %.*s (was %d instead of 1)", parsePtr->tokenPtr->size,
+		    parsePtr->tokenPtr->start, diff);
+	}
+#endif
+    }
 
-    Tcl_FreeParse(&synthetic);
     return result;
 }
 
@@ -3157,11 +3137,16 @@ CompileToInvokedCommand(
      */
 
     Tcl_ListObjGetElements(NULL, replacements, &numWords, &words);
-    for (i=0,tokPtr=parsePtr->tokenPtr ; i<parsePtr->numWords ; i++) {
+    for (i = 0, tokPtr = parsePtr->tokenPtr; i < parsePtr->numWords;
+	    i++, tokPtr = TokenAfter(tokPtr)) {
 	if (i > 0 && i < numWords+1) {
 	    bytes = Tcl_GetStringFromObj(words[i-1], &length);
 	    PushLiteral(envPtr, bytes, length);
-	} else if (tokPtr->type == TCL_TOKEN_SIMPLE_WORD) {
+	    continue;
+	}
+
+	SetLineInformation(i);
+	if (tokPtr->type == TCL_TOKEN_SIMPLE_WORD) {
 	    int literal = TclRegisterNewLiteral(envPtr,
 		    tokPtr[1].start, tokPtr[1].size);
 
@@ -3169,16 +3154,12 @@ CompileToInvokedCommand(
 		TclContinuationsEnterDerived(
 			TclFetchLiteral(envPtr, literal),
 			tokPtr[1].start - envPtr->source,
-			mapPtr->loc[eclIndex].next[i]);
+			envPtr->clNext);
 	    }
 	    TclEmitPush(literal, envPtr);
 	} else {
-	    if (envPtr->clNext) {
-		SetLineInformation(i);
-	    }
 	    CompileTokens(envPtr, tokPtr, interp);
 	}
-	tokPtr = TokenAfter(tokPtr);
     }
 
     /*
@@ -3224,51 +3205,13 @@ CompileBasicNArgCommand(
 				 * compiled. */
     CompileEnv *envPtr)		/* Holds resulting instructions. */
 {
-    Tcl_Token *tokenPtr;
-    Tcl_Obj *objPtr;
-    char *bytes;
-    int length, i, literal;
-    DefineLineInformation;
-
-    /*
-     * Push the name of the command we're actually dispatching to as part of
-     * the implementation.
-     */
+    Tcl_Obj *objPtr = Tcl_NewObj();
 
-    objPtr = Tcl_NewObj();
+    Tcl_IncrRefCount(objPtr);
     Tcl_GetCommandFullName(interp, (Tcl_Command) cmdPtr, objPtr);
-    bytes = Tcl_GetStringFromObj(objPtr, &length);
-    literal = TclRegisterNewCmdLiteral(envPtr, bytes, length);
-    TclSetCmdNameObj(interp, TclFetchLiteral(envPtr, literal), cmdPtr);
-    TclEmitPush(literal, envPtr);
-    TclDecrRefCount(objPtr);
-
-    /*
-     * Push the words of the command.
-     */
-
-    tokenPtr = TokenAfter(parsePtr->tokenPtr);
-    for (i=1 ; i<parsePtr->numWords ; i++) {
-	if (envPtr->clNext) {
-	    SetLineInformation(i);
-	}
-	if (tokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
-	    PushLiteral(envPtr, tokenPtr[1].start, tokenPtr[1].size);
-	} else {
-	    CompileTokens(envPtr, tokenPtr, interp);
-	}
-	tokenPtr = TokenAfter(tokenPtr);
-    }
-
-    /*
-     * Do the standard dispatch.
-     */
-
-    if (i <= 255) {
-	TclEmitInstInt1(INST_INVOKE_STK1, i, envPtr);
-    } else {
-	TclEmitInstInt4(INST_INVOKE_STK4, i, envPtr);
-    }
+    TclCompileInvocation(interp, parsePtr->tokenPtr, objPtr,
+	    parsePtr->numWords, envPtr);
+    Tcl_DecrRefCount(objPtr);
     return TCL_OK;
 }
 
diff --git a/generic/tclExecute.c b/generic/tclExecute.c
index d3a0d32..d066476 100644
--- a/generic/tclExecute.c
+++ b/generic/tclExecute.c
@@ -721,7 +721,7 @@ static ExceptionRange *	GetExceptRangeForPc(const unsigned char *pc,
 			    int catchOnly, ByteCode *codePtr);
 static const char *	GetSrcInfoForPc(const unsigned char *pc,
 			    ByteCode *codePtr, int *lengthPtr,
-			    const unsigned char **pcBeg);
+			    const unsigned char **pcBeg, int *cmdIdxPtr);
 static Tcl_Obj **	GrowEvaluationStack(ExecEnv *eePtr, int growth,
 			    int move);
 static void		IllegalExprOperandType(Tcl_Interp *interp,
@@ -1426,17 +1426,12 @@ Tcl_NRExprObj(
     Tcl_Obj *resultPtr)
 {
     ByteCode *codePtr;
+    Tcl_InterpState state = Tcl_SaveInterpState(interp, TCL_OK);
 
-    /* TODO: consider saving whole state? */
-    Tcl_Obj *saveObjPtr = Tcl_GetObjResult(interp);
-
-    Tcl_IncrRefCount(saveObjPtr);
-
+    Tcl_ResetResult(interp);
     codePtr = CompileExprObj(interp, objPtr);
 
-    /* TODO: Confirm reset not required? */
-    /*Tcl_ResetResult(interp);*/
-    Tcl_NRAddCallback(interp, ExprObjCallback, saveObjPtr, resultPtr,
+    Tcl_NRAddCallback(interp, ExprObjCallback, state, resultPtr,
 	    NULL, NULL);
     return TclNRExecuteByteCode(interp, codePtr);
 }
@@ -1447,14 +1442,15 @@ ExprObjCallback(
     Tcl_Interp *interp,
     int result)
 {
-    Tcl_Obj *saveObjPtr = data[0];
+    Tcl_InterpState state = data[0];
     Tcl_Obj *resultPtr = data[1];
 
     if (result == TCL_OK) {
 	TclSetDuplicateObj(resultPtr, Tcl_GetObjResult(interp));
-	Tcl_SetObjResult(interp, saveObjPtr);
+	(void) Tcl_RestoreInterpState(interp, state);
+    } else {
+	Tcl_DiscardInterpState(state);
     }
-    TclDecrRefCount(saveObjPtr);
     return result;
 }
 
@@ -2002,7 +1998,6 @@ TclNRExecuteByteCode(
     bcFramePtr->type = ((codePtr->flags & TCL_BYTECODE_PRECOMPILED)
 	    ? TCL_LOCATION_PREBC : TCL_LOCATION_BC);
     bcFramePtr->level = (iPtr->cmdFramePtr ? iPtr->cmdFramePtr->level+1 : 1);
-    bcFramePtr->numLevels = iPtr->numLevels;
     bcFramePtr->framePtr = iPtr->framePtr;
     bcFramePtr->nextPtr = iPtr->cmdFramePtr;
     bcFramePtr->nline = 0;
@@ -2010,8 +2005,9 @@ TclNRExecuteByteCode(
     bcFramePtr->litarg = NULL;
     bcFramePtr->data.tebc.codePtr = codePtr;
     bcFramePtr->data.tebc.pc = NULL;
-    bcFramePtr->cmd.str.cmd = NULL;
-    bcFramePtr->cmd.str.len = 0;
+    bcFramePtr->cmdObj = NULL;
+    bcFramePtr->cmd = NULL;
+    bcFramePtr->len = 0;
 
 #ifdef TCL_COMPILE_STATS
     iPtr->stats.numExecutions++;
@@ -2134,6 +2130,11 @@ TEBCresume(
 	    result = TCL_ERROR;
 	}
 	NRE_ASSERT(iPtr->cmdFramePtr == bcFramePtr);
+	if (bcFramePtr->cmdObj) {
+	    Tcl_DecrRefCount(bcFramePtr->cmdObj);
+	    bcFramePtr->cmdObj = NULL;
+	    bcFramePtr->cmd = NULL;
+	}
 	iPtr->cmdFramePtr = bcFramePtr->nextPtr;
 	if (iPtr->flags & INTERP_DEBUG_FRAME) {
 	    TclArgumentBCRelease((Tcl_Interp *) iPtr, bcFramePtr);
@@ -2435,8 +2436,11 @@ TEBCresume(
 	iPtr->cmdFramePtr = bcFramePtr;
 
 	if (iPtr->flags & INTERP_DEBUG_FRAME) {
-	    TclArgumentBCEnter((Tcl_Interp *) iPtr, objv, objc,
-		    codePtr, bcFramePtr, pc - codePtr->codeStart);
+	    int cmd;
+	    if (GetSrcInfoForPc(pc, codePtr, NULL, NULL, &cmd)) {
+		TclArgumentBCEnter((Tcl_Interp *) iPtr, objv, objc,
+			codePtr, bcFramePtr, cmd, pc - codePtr->codeStart);
+	    }
 	}
 
 	pc++;
@@ -2889,8 +2893,11 @@ TEBCresume(
 	iPtr->cmdFramePtr = bcFramePtr;
 
 	if (iPtr->flags & INTERP_DEBUG_FRAME) {
-	    TclArgumentBCEnter((Tcl_Interp *) iPtr, objv, objc,
-		    codePtr, bcFramePtr, pc - codePtr->codeStart);
+	    int cmd;
+	    if (GetSrcInfoForPc(pc, codePtr, NULL, NULL, &cmd)) {
+		TclArgumentBCEnter((Tcl_Interp *) iPtr, objv, objc,
+			codePtr, bcFramePtr, cmd, pc - codePtr->codeStart);
+	    }
 	}
 
 	DECACHE_STACK_INFO();
@@ -2898,7 +2905,7 @@ TEBCresume(
 	pc += pcAdjustment;
 	TEBC_YIELD();
 	return TclNREvalObjv(interp, objc, objv,
-		TCL_EVAL_NOERR, NULL);
+		TCL_EVAL_NOERR | TCL_EVAL_SOURCE_IN_FRAME, NULL);
 
 #if TCL_SUPPORT_84_BYTECODE
     case INST_CALL_BUILTIN_FUNC1:
@@ -3035,8 +3042,11 @@ TEBCresume(
 	bcFramePtr->data.tebc.pc = (char *) pc;
 	iPtr->cmdFramePtr = bcFramePtr;
 	if (iPtr->flags & INTERP_DEBUG_FRAME) {
-	    TclArgumentBCEnter((Tcl_Interp *) iPtr, objv, objc,
-		    codePtr, bcFramePtr, pc - codePtr->codeStart);
+	    int cmd;
+	    if (GetSrcInfoForPc(pc, codePtr, NULL, NULL, &cmd)) {
+		TclArgumentBCEnter((Tcl_Interp *) iPtr, objv, objc,
+			codePtr, bcFramePtr, cmd, pc - codePtr->codeStart);
+	    }
 	}
 	iPtr->ensembleRewrite.sourceObjs = objv;
 	iPtr->ensembleRewrite.numRemovedObjs = opnd;
@@ -6971,7 +6981,7 @@ TEBCresume(
 	if ((result == TCL_ERROR) && !(iPtr->flags & ERR_ALREADY_LOGGED)) {
 	    const unsigned char *pcBeg;
 
-	    bytes = GetSrcInfoForPc(pc, codePtr, &length, &pcBeg);
+	    bytes = GetSrcInfoForPc(pc, codePtr, &length, &pcBeg, NULL);
 	    DECACHE_STACK_INFO();
 	    TclLogCommandInfo(interp, codePtr->source, bytes,
 		    bytes ? length : 0, pcBeg, tosPtr);
@@ -7153,7 +7163,7 @@ TEBCresume(
 	    }
 
 	    codePtr->flags |= TCL_BYTECODE_RECOMPILE;
-	    bytes = GetSrcInfoForPc(pc, codePtr, &length, NULL);
+	    bytes = GetSrcInfoForPc(pc, codePtr, &length, NULL, NULL);
 	    opnd = TclGetUInt4AtPtr(pc+1);
 	    pc += (opnd-1);
 	    PUSH_OBJECT(Tcl_NewStringObj(bytes, length));
@@ -8646,7 +8656,7 @@ ValidatePcAndStackTop(
     if (checkStack && 
 	    ((stackTop < 0) || (stackTop > stackUpperBound))) {
 	int numChars;
-	const char *cmd = GetSrcInfoForPc(pc, codePtr, &numChars, NULL);
+	const char *cmd = GetSrcInfoForPc(pc, codePtr, &numChars, NULL, NULL);
 
 	fprintf(stderr, "\nBad stack top %d at pc %u in TclNRExecuteByteCode (min 0, max %i)",
 		stackTop, relativePc, stackUpperBound);
@@ -8730,7 +8740,7 @@ IllegalExprOperandType(
 /*
  *----------------------------------------------------------------------
  *
- * TclGetSrcInfoForPc, GetSrcInfoForPc, TclGetSrcInfoForCmd --
+ * TclGetSrcInfoForPc, GetSrcInfoForPc, TclGetSourceFromFrame --
  *
  *	Given a program counter value, finds the closest command in the
  *	bytecode code unit's CmdLocation array and returns information about
@@ -8751,16 +8761,26 @@ IllegalExprOperandType(
  *----------------------------------------------------------------------
  */
 
-const char *
-TclGetSrcInfoForCmd(
-    Interp *iPtr,
-    int *lenPtr)
+Tcl_Obj *
+TclGetSourceFromFrame(
+    CmdFrame *cfPtr,
+    int objc,
+    Tcl_Obj *const objv[])
 {
-    CmdFrame *cfPtr = iPtr->cmdFramePtr;
-    ByteCode *codePtr = (ByteCode *) cfPtr->data.tebc.codePtr;
-
-    return GetSrcInfoForPc((unsigned char *) cfPtr->data.tebc.pc,
-	    codePtr, lenPtr, NULL);
+    if (cfPtr == NULL) {
+        return Tcl_NewListObj(objc, objv);
+    }
+    if (cfPtr->cmdObj == NULL) {
+        if (cfPtr->cmd == NULL) {
+	    ByteCode *codePtr = (ByteCode *) cfPtr->data.tebc.codePtr;
+
+            cfPtr->cmd = GetSrcInfoForPc((unsigned char *)
+		    cfPtr->data.tebc.pc, codePtr, &cfPtr->len, NULL, NULL);
+        }
+        cfPtr->cmdObj = Tcl_NewStringObj(cfPtr->cmd, cfPtr->len);
+        Tcl_IncrRefCount(cfPtr->cmdObj);
+    }
+    return cfPtr->cmdObj;
 }
 
 void
@@ -8769,13 +8789,17 @@ TclGetSrcInfoForPc(
 {
     ByteCode *codePtr = (ByteCode *) cfPtr->data.tebc.codePtr;
 
-    if (cfPtr->cmd.str.cmd == NULL) {
-	cfPtr->cmd.str.cmd = GetSrcInfoForPc(
+    assert(cfPtr->type == TCL_LOCATION_BC);
+
+    if (cfPtr->cmd == NULL) {
+
+	cfPtr->cmd = GetSrcInfoForPc(
 		(unsigned char *) cfPtr->data.tebc.pc, codePtr,
-		&cfPtr->cmd.str.len, NULL);
+		&cfPtr->len, NULL, NULL);
     }
 
-    if (cfPtr->cmd.str.cmd != NULL) {
+    assert(cfPtr->cmd != NULL);
+    {
 	/*
 	 * We now have the command. We can get the srcOffset back and from
 	 * there find the list of word locations for this command.
@@ -8792,7 +8816,7 @@ TclGetSrcInfoForPc(
 	    return;
 	}
 
-	srcOffset = cfPtr->cmd.str.cmd - codePtr->source;
+	srcOffset = cfPtr->cmd - codePtr->source;
 	eclPtr = Tcl_GetHashValue(hePtr);
 
 	for (i=0; i < eclPtr->nuloc; i++) {
@@ -8832,9 +8856,12 @@ GetSrcInfoForPc(
     int *lengthPtr,		/* If non-NULL, the location where the length
 				 * of the command's source should be stored.
 				 * If NULL, no length is stored. */
-    const unsigned char **pcBeg)/* If non-NULL, the bytecode location
+    const unsigned char **pcBeg,/* If non-NULL, the bytecode location
 				 * where the current instruction starts.
 				 * If NULL; no pointer is stored. */
+    int *cmdIdxPtr)		/* If non-NULL, the location where the index
+				 * of the command containing the pc should 
+				 * be stored. */
 {
     register int pcOffset = (pc - codePtr->codeStart);
     int numCmds = codePtr->numCommands;
@@ -8844,6 +8871,7 @@ GetSrcInfoForPc(
     int bestDist = INT_MAX;	/* Distance of pc to best cmd's start pc. */
     int bestSrcOffset = -1;	/* Initialized to avoid compiler warning. */
     int bestSrcLength = -1;	/* Initialized to avoid compiler warning. */
+    int bestCmdIdx = -1;
 
     if ((pcOffset < 0) || (pcOffset >= codePtr->numCodeBytes)) {
 	if (pcBeg != NULL) *pcBeg = NULL;
@@ -8911,6 +8939,7 @@ GetSrcInfoForPc(
 		bestDist = dist;
 		bestSrcOffset = srcOffset;
 		bestSrcLength = srcLen;
+		bestCmdIdx = i;
 	    }
 	}
     }
@@ -8940,6 +8969,10 @@ GetSrcInfoForPc(
 	*lengthPtr = bestSrcLength;
     }
 
+    if (cmdIdxPtr != NULL) {
+	*cmdIdxPtr = bestCmdIdx;
+    }
+
     return (codePtr->source + bestSrcOffset);
 }
 
diff --git a/generic/tclInt.h b/generic/tclInt.h
index b940225..6056119 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -1175,29 +1175,27 @@ typedef struct CmdFrame {
      *
      * EXECUTION CONTEXTS and usage of CmdFrame
      *
-     * Field	  TEBC		  EvalEx	  EvalObjEx
-     * =======	  ====		  ======	  =========
-     * level	  yes		  yes		  yes
-     * type	  BC/PREBC	  SRC/EVAL	  EVAL_LIST
-     * line0	  yes		  yes		  yes
-     * framePtr	  yes		  yes		  yes
-     * =======	  ====		  ======	  =========
+     * Field	  TEBC		  EvalEx
+     * =======	  ====		  ======
+     * level	  yes		  yes	
+     * type	  BC/PREBC	  SRC/EVAL
+     * line0	  yes		  yes	
+     * framePtr	  yes		  yes	
+     * =======	  ====		  ======
      *
-     * =======	  ====		  ======	  ========= union data
-     * line1	  -		  yes		  -
-     * line3	  -		  yes		  -
-     * path	  -		  yes		  -
-     * -------	  ----		  ------	  ---------
-     * codePtr	  yes		  -		  -
-     * pc	  yes		  -		  -
-     * =======	  ====		  ======	  =========
+     * =======	  ====		  ========= union data
+     * line1	  -		  yes	
+     * line3	  -		  yes	
+     * path	  -		  yes	
+     * -------	  ----		  ------
+     * codePtr	  yes		  -	
+     * pc	  yes		  -	
+     * =======	  ====		  ======
      *
-     * =======	  ====		  ======	  ========= | union cmd
-     * listPtr	  -		  -		  yes	    |
-     * -------	  ----		  ------	  --------- |
-     * cmd	  yes		  yes		  -	    |
-     * cmdlen	  yes		  yes		  -	    |
-     * -------	  ----		  ------	  --------- |
+     * =======	  ====		  ========= union cmd
+     * str.cmd	  yes		  yes	
+     * str.len	  yes		  yes	
+     * -------	  ----		  ------	
      */
 
     union {
@@ -1210,15 +1208,9 @@ typedef struct CmdFrame {
 	    const char *pc;	/* ... and instruction pointer. */
 	} tebc;
     } data;
-    union {
-	struct {
-	    const char *cmd;	/* The executed command, if possible... */
-	    int len;		/* ... and its length. */
-	} str;
-	Tcl_Obj *listPtr;	/* Tcl_EvalObjEx, cmd list. */
-    } cmd;
-    int numLevels;		/* Value of interp's numLevels when the frame
-				 * was pushed. */
+    Tcl_Obj *cmdObj;
+    const char *cmd;		/* The executed command, if possible... */
+    int len;			/* ... and its length. */
     const struct CFWordBC *litarg;
 				/* Link to set of literal arguments which have
 				 * ben pushed on the lineLABCPtr stack by
@@ -1282,8 +1274,6 @@ typedef struct ContLineLoc {
  * location data referenced via the 'baseLocPtr'.
  *
  * TCL_LOCATION_EVAL	  : Frame is for a script evaluated by EvalEx.
- * TCL_LOCATION_EVAL_LIST : Frame is for a script evaluated by the list
- *			    optimization path of EvalObjEx.
  * TCL_LOCATION_BC	  : Frame is for bytecode.
  * TCL_LOCATION_PREBC	  : Frame is for precompiled bytecode.
  * TCL_LOCATION_SOURCE	  : Frame is for a script evaluated by EvalEx, from a
@@ -1295,8 +1285,6 @@ typedef struct ContLineLoc {
  */
 
 #define TCL_LOCATION_EVAL	(0) /* Location in a dynamic eval script. */
-#define TCL_LOCATION_EVAL_LIST	(1) /* Location in a dynamic eval script,
-				     * list-path. */
 #define TCL_LOCATION_BC		(2) /* Location in byte code. */
 #define TCL_LOCATION_PREBC	(3) /* Location in precompiled byte code, no
 				     * location. */
@@ -2210,9 +2198,9 @@ typedef struct Interp {
  *			other than these should be turned into errors.
  */
 
-#define TCL_ALLOW_EXCEPTIONS	4
-#define TCL_EVAL_FILE		2
-#define TCL_EVAL_CTX		8
+#define TCL_ALLOW_EXCEPTIONS		0x04
+#define TCL_EVAL_FILE			0x02
+#define TCL_EVAL_SOURCE_IN_FRAME	0x10
 
 /*
  * Flag bits for Interp structures:
@@ -2828,7 +2816,7 @@ MODULE_SCOPE void	TclArgumentRelease(Tcl_Interp *interp,
 			    Tcl_Obj *objv[], int objc);
 MODULE_SCOPE void	TclArgumentBCEnter(Tcl_Interp *interp,
 			    Tcl_Obj *objv[], int objc,
-			    void *codePtr, CmdFrame *cfPtr, int pc);
+			    void *codePtr, CmdFrame *cfPtr, int cmd, int pc);
 MODULE_SCOPE void	TclArgumentBCRelease(Tcl_Interp *interp,
 			    CmdFrame *cfPtr);
 MODULE_SCOPE void	TclArgumentGet(Tcl_Interp *interp, Tcl_Obj *obj,
@@ -2919,7 +2907,8 @@ MODULE_SCOPE int	TclGetOpenModeEx(Tcl_Interp *interp,
 			    const char *modeString, int *seekFlagPtr,
 			    int *binaryPtr);
 MODULE_SCOPE Tcl_Obj *	TclGetProcessGlobalValue(ProcessGlobalValue *pgvPtr);
-MODULE_SCOPE const char *TclGetSrcInfoForCmd(Interp *iPtr, int *lenPtr);
+MODULE_SCOPE Tcl_Obj *	TclGetSourceFromFrame(CmdFrame *cfPtr, int objc,
+			    Tcl_Obj *const objv[]);
 MODULE_SCOPE int	TclGlob(Tcl_Interp *interp, char *pattern,
 			    Tcl_Obj *unquotedPrefix, int globFlags,
 			    Tcl_GlobTypeData *types);
diff --git a/generic/tclOODefineCmds.c b/generic/tclOODefineCmds.c
index bacab38..f0983cc 100644
--- a/generic/tclOODefineCmds.c
+++ b/generic/tclOODefineCmds.c
@@ -2206,29 +2206,42 @@ ClassSuperSet(
 
     /*
      * Parse the arguments to get the class to use as superclasses.
+     *
+     * Note that zero classes is special, as it is equivalent to just the
+     * class of objects. [Bug 9d61624b3d]
      */
 
-    for (i=0 ; i<superc ; i++) {
-	superclasses[i] = GetClassInOuterContext(interp, superv[i],
-		"only a class can be a superclass");
-	if (superclasses[i] == NULL) {
-	    goto failedAfterAlloc;
+    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;
 	}
-	for (j=0 ; j<i ; j++) {
-	    if (superclasses[j] == superclasses[i]) {
-		Tcl_SetObjResult(interp, Tcl_NewStringObj(
-			"class should only be a direct superclass once", -1));
-		Tcl_SetErrorCode(interp, "TCL", "OO", "REPETITIOUS", NULL);
+    } else {
+	for (i=0 ; i<superc ; i++) {
+	    superclasses[i] = GetClassInOuterContext(interp, superv[i],
+		    "only a class can be a superclass");
+	    if (superclasses[i] == NULL) {
 		goto failedAfterAlloc;
 	    }
-	}
-	if (TclOOIsReachable(oPtr->classPtr, superclasses[i])) {
-	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
-		    "attempt to form circular dependency graph", -1));
-	    Tcl_SetErrorCode(interp, "TCL", "OO", "CIRCULARITY", NULL);
-	failedAfterAlloc:
-	    ckfree((char *) superclasses);
-	    return TCL_ERROR;
+	    for (j=0 ; j<i ; j++) {
+		if (superclasses[j] == superclasses[i]) {
+		    Tcl_SetObjResult(interp, Tcl_NewStringObj(
+			    "class should only be a direct superclass once",
+			    -1));
+		    Tcl_SetErrorCode(interp, "TCL", "OO", "REPETITIOUS",NULL);
+		    goto failedAfterAlloc;
+		}
+	    }
+	    if (TclOOIsReachable(oPtr->classPtr, superclasses[i])) {
+		Tcl_SetObjResult(interp, Tcl_NewStringObj(
+			"attempt to form circular dependency graph", -1));
+		Tcl_SetErrorCode(interp, "TCL", "OO", "CIRCULARITY", NULL);
+	    failedAfterAlloc:
+		ckfree((char *) superclasses);
+		return TCL_ERROR;
+	    }
 	}
     }
 
diff --git a/generic/tclOOInt.h b/generic/tclOOInt.h
index ab54964..c0e4022 100644
--- a/generic/tclOOInt.h
+++ b/generic/tclOOInt.h
@@ -122,12 +122,6 @@ typedef struct ForwardMethod {
     Tcl_Obj *prefixObj;		/* The list of values to use to replace the
 				 * object and method name with. Will be a
 				 * non-empty list. */
-    int fullyQualified;		/* If 1, the command name is fully qualified
-				 * and we should let the default Tcl mechanism
-				 * handle the command lookup because it is
-				 * more efficient. If 0, we need to do a
-				 * specialized lookup based on the current
-				 * object's namespace. */
 } ForwardMethod;
 
 /*
diff --git a/generic/tclOOMethod.c b/generic/tclOOMethod.c
index 98b4078..f9f980a 100644
--- a/generic/tclOOMethod.c
+++ b/generic/tclOOMethod.c
@@ -513,8 +513,8 @@ TclOOMakeProcInstanceMethod(
 		cfPtr->data.eval.path = context.data.eval.path;
 		Tcl_IncrRefCount(cfPtr->data.eval.path);
 
-		cfPtr->cmd.str.cmd = NULL;
-		cfPtr->cmd.str.len = 0;
+		cfPtr->cmd = NULL;
+		cfPtr->len = 0;
 
 		hPtr = Tcl_CreateHashEntry(iPtr->linePBodyPtr,
 			(char *) procPtr, &isNew);
@@ -626,8 +626,8 @@ TclOOMakeProcMethod(
 		cfPtr->data.eval.path = context.data.eval.path;
 		Tcl_IncrRefCount(cfPtr->data.eval.path);
 
-		cfPtr->cmd.str.cmd = NULL;
-		cfPtr->cmd.str.len = 0;
+		cfPtr->cmd = NULL;
+		cfPtr->len = 0;
 
 		hPtr = Tcl_CreateHashEntry(iPtr->linePBodyPtr,
 			(char *) procPtr, &isNew);
@@ -1338,7 +1338,6 @@ TclOONewForwardInstanceMethod(
     fmPtr = ckalloc(sizeof(ForwardMethod));
     fmPtr->prefixObj = prefixObj;
     Tcl_ListObjIndex(interp, prefixObj, 0, &cmdObj);
-    fmPtr->fullyQualified = (strncmp(TclGetString(cmdObj), "::", 2) == 0);
     Tcl_IncrRefCount(prefixObj);
     return (Method *) Tcl_NewInstanceMethod(interp, (Tcl_Object) oPtr,
 	    nameObj, flags, &fwdMethodType, fmPtr);
@@ -1380,7 +1379,6 @@ TclOONewForwardMethod(
     fmPtr = ckalloc(sizeof(ForwardMethod));
     fmPtr->prefixObj = prefixObj;
     Tcl_ListObjIndex(interp, prefixObj, 0, &cmdObj);
-    fmPtr->fullyQualified = (strncmp(TclGetString(cmdObj), "::", 2) == 0);
     Tcl_IncrRefCount(prefixObj);
     return (Method *) Tcl_NewMethod(interp, (Tcl_Class) clsPtr, nameObj,
 	    flags, &fwdMethodType, fmPtr);
@@ -1409,7 +1407,6 @@ InvokeForwardMethod(
     ForwardMethod *fmPtr = clientData;
     Tcl_Obj **argObjs, **prefixObjs;
     int numPrefixes, len, skip = contextPtr->skip;
-    Command *cmdPtr;
 
     /*
      * Build the real list of arguments to use. Note that we know that the
@@ -1421,15 +1418,10 @@ InvokeForwardMethod(
     Tcl_ListObjGetElements(NULL, fmPtr->prefixObj, &numPrefixes, &prefixObjs);
     argObjs = InitEnsembleRewrite(interp, objc, objv, skip,
 	    numPrefixes, prefixObjs, &len);
-
-    if (fmPtr->fullyQualified) {
-	cmdPtr = NULL;
-    } else {
-	cmdPtr = (Command *) Tcl_FindCommand(interp, TclGetString(argObjs[0]),
-		contextPtr->oPtr->namespacePtr, 0 /* normal lookup */);
-    }
     Tcl_NRAddCallback(interp, FinalizeForwardCall, argObjs, NULL, NULL, NULL);
-    return TclNREvalObjv(interp, len, argObjs, TCL_EVAL_INVOKE, cmdPtr);
+    ((Interp *)interp)->lookupNsPtr
+	    = (Namespace *) contextPtr->oPtr->namespacePtr;
+    return TclNREvalObjv(interp, len, argObjs, TCL_EVAL_INVOKE, NULL);
 }
 
 static int
@@ -1474,7 +1466,6 @@ CloneForwardMethod(
     ForwardMethod *fm2Ptr = ckalloc(sizeof(ForwardMethod));
 
     fm2Ptr->prefixObj = fmPtr->prefixObj;
-    fm2Ptr->fullyQualified = fmPtr->fullyQualified;
     Tcl_IncrRefCount(fm2Ptr->prefixObj);
     *newClientData = fm2Ptr;
     return TCL_OK;
diff --git a/generic/tclObj.c b/generic/tclObj.c
index 542d6d1..930e1fd 100644
--- a/generic/tclObj.c
+++ b/generic/tclObj.c
@@ -97,7 +97,6 @@ typedef struct ThreadSpecificData {
 
 static Tcl_ThreadDataKey dataKey;
 
-static void             ContLineLocFree(char *clientData);
 static void             TclThreadFinalizeContLines(ClientData clientData);
 static ThreadSpecificData *TclGetContLineTable(void);
 
@@ -805,14 +804,7 @@ TclThreadFinalizeContLines(
 
     for (hPtr = Tcl_FirstHashEntry(tsdPtr->lineCLPtr, &hSearch);
 	    hPtr != NULL; hPtr = Tcl_NextHashEntry(&hSearch)) {
-	/*
-	 * We are not using Tcl_EventuallyFree (as in TclFreeObj()) because
-	 * here we can be sure that the compiler will not hold references to
-	 * the data in the hashtable, and using TEF might bork the
-	 * finalization sequence.
-	 */
-
-	ContLineLocFree(Tcl_GetHashValue(hPtr));
+	ckfree(Tcl_GetHashValue(hPtr));
 	Tcl_DeleteHashEntry(hPtr);
     }
     Tcl_DeleteHashTable(tsdPtr->lineCLPtr);
@@ -821,30 +813,6 @@ TclThreadFinalizeContLines(
 }
 
 /*
- *----------------------------------------------------------------------
- *
- * ContLineLocFree --
- *
- *	The freProc for continuation line location tables.
- *
- * Results:
- *	None.
- *
- * Side effects:
- *	Releases memory.
- *
- * TIP #280
- *----------------------------------------------------------------------
- */
-
-static void
-ContLineLocFree(
-    char *clientData)
-{
-    ckfree(clientData);
-}
-
-/*
  *--------------------------------------------------------------
  *
  * Tcl_RegisterObjType --
@@ -1405,7 +1373,7 @@ TclFreeObj(
 	if (tsdPtr->lineCLPtr) {
             hPtr = Tcl_FindHashEntry(tsdPtr->lineCLPtr, objPtr);
 	    if (hPtr) {
-		Tcl_EventuallyFree(Tcl_GetHashValue(hPtr), ContLineLocFree);
+		ckfree(Tcl_GetHashValue(hPtr));
 		Tcl_DeleteHashEntry(hPtr);
 	    }
 	}
@@ -1496,7 +1464,7 @@ TclFreeObj(
 	if (tsdPtr->lineCLPtr) {
             hPtr = Tcl_FindHashEntry(tsdPtr->lineCLPtr, objPtr);
 	    if (hPtr) {
-		Tcl_EventuallyFree(Tcl_GetHashValue(hPtr), ContLineLocFree);
+		ckfree(Tcl_GetHashValue(hPtr));
 		Tcl_DeleteHashEntry(hPtr);
 	    }
 	}
diff --git a/generic/tclParse.c b/generic/tclParse.c
index 08615a7..c5cb1d1 100644
--- a/generic/tclParse.c
+++ b/generic/tclParse.c
@@ -13,6 +13,7 @@
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  */
  
+#include <assert.h>
 #include "tclInt.h"
 #include "tclParse.h"
 
@@ -1567,6 +1568,7 @@ Tcl_ParseVar(
 
     code = TclSubstTokens(interp, parsePtr->tokenPtr, parsePtr->numTokens,
 	    NULL, 1, NULL, NULL);
+    Tcl_FreeParse(parsePtr);
     TclStackFree(interp, parsePtr);
     if (code != TCL_OK) {
 	return NULL;
@@ -1577,16 +1579,13 @@ Tcl_ParseVar(
      * At this point we should have an object containing the value of a
      * variable. Just return the string from that object.
      *
-     * This should have returned the object for the user to manage, but
-     * instead we have some weak reference to the string value in the object,
-     * which is why we make sure the object exists after resetting the result.
-     * This isn't ideal, but it's the best we can do with the current
-     * documented interface. -- hobbs
+     * Since TclSubstTokens above returned TCL_OK, we know that objPtr
+     * is shared.  It is in both the interp result and the value of the
+     * variable.  Returning the string relies on that to be true.
      */
 
-    if (!Tcl_IsShared(objPtr)) {
-	Tcl_IncrRefCount(objPtr);
-    }
+    assert( Tcl_IsShared(objPtr) );
+
     Tcl_ResetResult(interp);
     return TclGetString(objPtr);
 }
diff --git a/generic/tclProc.c b/generic/tclProc.c
index 23d8e70..a154afa 100644
--- a/generic/tclProc.c
+++ b/generic/tclProc.c
@@ -267,8 +267,8 @@ Tcl_ProcObjCmd(
 		cfPtr->data.eval.path = contextPtr->data.eval.path;
 		Tcl_IncrRefCount(cfPtr->data.eval.path);
 
-		cfPtr->cmd.str.cmd = NULL;
-		cfPtr->cmd.str.len = 0;
+		cfPtr->cmd = NULL;
+		cfPtr->len = 0;
 
 		hePtr = Tcl_CreateHashEntry(iPtr->linePBodyPtr,
 			procPtr, &isNew);
@@ -2591,8 +2591,8 @@ SetLambdaFromAny(
 		cfPtr->data.eval.path = contextPtr->data.eval.path;
 		Tcl_IncrRefCount(cfPtr->data.eval.path);
 
-		cfPtr->cmd.str.cmd = NULL;
-		cfPtr->cmd.str.len = 0;
+		cfPtr->cmd = NULL;
+		cfPtr->len = 0;
 	    }
 
 	    /*
diff --git a/generic/tclTest.c b/generic/tclTest.c
index 27ee89c..96973d7 100644
--- a/generic/tclTest.c
+++ b/generic/tclTest.c
@@ -1555,14 +1555,14 @@ DelCallbackProc(
  *
  * TestdelCmd --
  *
- *	This procedure implements the "testdcall" command.  It is used
- *	to test Tcl_CallWhenDeleted.
+ *	This procedure implements the "testdel" command.  It is used
+ *	to test calling of command deletion callbacks.
  *
  * Results:
  *	A standard Tcl result.
  *
  * Side effects:
- *	Creates and deletes interpreters.
+ *	Creates a command.
  *
  *----------------------------------------------------------------------
  */
diff --git a/generic/tclUtf.c b/generic/tclUtf.c
index 0af2c25..15529c7 100644
--- a/generic/tclUtf.c
+++ b/generic/tclUtf.c
@@ -1555,10 +1555,10 @@ Tcl_UniCharIsSpace(
      */
 
     if (((Tcl_UniChar) ch) < ((Tcl_UniChar) 0x80)) {
-	return TclIsSpaceProc(ch);
+	return TclIsSpaceProc((char) ch);
     } else if ((Tcl_UniChar) ch == 0x0085 || (Tcl_UniChar) ch == 0x180e
 	    || (Tcl_UniChar) ch == 0x200b || (Tcl_UniChar) ch == 0x2060
-	    || (Tcl_UniChar) ch == 0xfeff) {
+	    || (Tcl_UniChar) ch == 0x202f || (Tcl_UniChar) ch == 0xfeff) {
 	return 1;
     } else {
 	return ((SPACE_BITS >> GetCategory(ch)) & 1);