Add compilation for TIP#90-style [catch] requiring a new opcode [Bug1219112]

5 files changed, 541 insertions, 494 deletions

diff --git a/ChangeLog b/ChangeLog
index 9c23a7e..c12c388 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2005-06-20  Donal K. Fellows  <dkf@users.sf.net>
 
+	* generic/tclCompile.h (INST_PUSH_RETURN_OPTIONS): New opcode to allow
+	* generic/tclCompCmds.c (TclCompileCatchCmd):	   compilation of TIP90
+	* generic/tclCompile.c:				   catch [Bug 1219112]
+	* generic/tclExecute.c (TclExecuteByteCode): 
+
 	* generic/tclCompCmds.c (TclCompileSwitchCmd): Ensure we spill to the
 	command form in all cases where it generates an error.
 
diff --git a/generic/tclCompCmds.c b/generic/tclCompCmds.c
index be74f2a..aefd8e3 100644
--- a/generic/tclCompCmds.c
+++ b/generic/tclCompCmds.c
@@ -12,7 +12,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclCompCmds.c,v 1.73 2005/06/20 10:01:47 dkf Exp $
+ * RCS: @(#) $Id: tclCompCmds.c,v 1.74 2005/06/20 21:27:09 dkf Exp $
  */
 
 #include "tclInt.h"
@@ -264,50 +264,65 @@ TclCompileCatchCmd(interp, parsePtr, envPtr)
     CompileEnv *envPtr;		/* Holds resulting instructions. */
 {
     JumpFixup jumpFixup;
-    Tcl_Token *cmdTokenPtr, *nameTokenPtr;
+    Tcl_Token *cmdTokenPtr, *resultNameTokenPtr, *optsNameTokenPtr;
     CONST char *name;
-    int localIndex, nameChars, range, startOffset;
+    int resultIndex, optsIndex, nameChars, range, startOffset;
     int savedStackDepth = envPtr->currStackDepth;
 
     /*
      * If syntax does not match what we expect for [catch], do not compile.
      * Let runtime checks determine if syntax has changed.
      */
-    if ((parsePtr->numWords != 2) && (parsePtr->numWords != 3)) {
+    if ((parsePtr->numWords < 2) && (parsePtr->numWords > 4)) {
 	return TCL_ERROR;
     }
 
     /*
-     * If a variable was specified and the catch command is at global level
+     * If variables were specified and the catch command is at global level
      * (not in a procedure), don't compile it inline: the payoff is too small.
      */
 
-    if ((parsePtr->numWords == 3) && (envPtr->procPtr == NULL)) {
+    if ((parsePtr->numWords >= 3) && (envPtr->procPtr == NULL)) {
 	return TCL_ERROR;
     }
 
     /*
-     * Make sure the variable name, if any, has no substitutions and just
-     * refers to a local scaler.
+     * Make sure the variable names, if any, have no substitutions and just
+     * refer to local scalars.
      */
 
-    localIndex = -1;
+    resultIndex = optsIndex = -1;
     cmdTokenPtr = TokenAfter(parsePtr->tokenPtr);
-    if (parsePtr->numWords == 3) {
-	nameTokenPtr = TokenAfter(cmdTokenPtr);
+    if (parsePtr->numWords >= 3) {
+	resultNameTokenPtr = TokenAfter(cmdTokenPtr);
 	/* DGP */
-	if (nameTokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
-	    name = nameTokenPtr[1].start;
-	    nameChars = nameTokenPtr[1].size;
+	if (resultNameTokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
+	    name = resultNameTokenPtr[1].start;
+	    nameChars = resultNameTokenPtr[1].size;
 	    if (!TclIsLocalScalar(name, nameChars)) {
 		return TCL_ERROR;
 	    }
-	    localIndex = TclFindCompiledLocal(nameTokenPtr[1].start,
-		    nameTokenPtr[1].size, /*create*/ 1, VAR_SCALAR,
+	    resultIndex = TclFindCompiledLocal(resultNameTokenPtr[1].start,
+		    resultNameTokenPtr[1].size, /*create*/ 1, VAR_SCALAR,
 		    envPtr->procPtr);
 	} else {
 	   return TCL_ERROR;
 	}
+	/* DKF */
+	if (parsePtr->numWords == 4) {
+	    optsNameTokenPtr = TokenAfter(resultNameTokenPtr);
+	    if (optsNameTokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+		return TCL_ERROR;
+	    }
+	    name = optsNameTokenPtr[1].start;
+	    nameChars = optsNameTokenPtr[1].size;
+	    if (!TclIsLocalScalar(name, nameChars)) {
+		return TCL_ERROR;
+	    }
+	    optsIndex = TclFindCompiledLocal(optsNameTokenPtr[1].start,
+		    optsNameTokenPtr[1].size, /*create*/ 1, VAR_SCALAR,
+		    envPtr->procPtr);
+	}
     }
 
     /*
@@ -346,14 +361,31 @@ TclCompileCatchCmd(interp, parsePtr, envPtr)
     /*
      * The "no errors" epilogue code: store the body's result into the
      * variable (if any), push "0" (TCL_OK) as the catch's "no error" result,
-     * and jump around the "error case" code.
+     * and jump around the "error case" code. Note that we issue the push of
+     * the return options first so that if alterations happen to the current
+     * interpreter state during the writing of the variable, we won't see
+     * them; this results in a slightly complex instruction issuing flow
+     * (can't exchange, only duplicate and pop).
      */
 
-    if (localIndex != -1) {
-	if (localIndex <= 255) {
-	    TclEmitInstInt1(INST_STORE_SCALAR1, localIndex, envPtr);
+    if (resultIndex != -1) {
+	if (optsIndex != -1) {
+	    TclEmitOpcode(INST_PUSH_RETURN_OPTIONS, envPtr);
+	    TclEmitInstInt4(INST_OVER, 1, envPtr);
+	}
+	if (resultIndex <= 255) {
+	    TclEmitInstInt1(INST_STORE_SCALAR1, resultIndex, envPtr);
 	} else {
-	    TclEmitInstInt4(INST_STORE_SCALAR4, localIndex, envPtr);
+	    TclEmitInstInt4(INST_STORE_SCALAR4, resultIndex, envPtr);
+	}
+	if (optsIndex != -1) {
+	    TclEmitOpcode(INST_POP, envPtr);
+	    if (optsIndex <= 255) {
+		TclEmitInstInt1(INST_STORE_SCALAR1, optsIndex, envPtr);
+	    } else {
+		TclEmitInstInt4(INST_STORE_SCALAR4, optsIndex, envPtr);
+	    }
+	    TclEmitOpcode(INST_POP, envPtr);
 	}
     }
     TclEmitOpcode(INST_POP, envPtr);
@@ -363,23 +395,35 @@ TclCompileCatchCmd(interp, parsePtr, envPtr)
     /*
      * The "error case" code: store the body's result into the variable (if
      * any), then push the error result code. The initial PC offset here is
-     * the catch's error target.
+     * the catch's error target. Note that if we are saving the return
+     * options, we do that first so the preservation cannot get affected by
+     * any intermediate result handling.
      */
 
     envPtr->currStackDepth = savedStackDepth;
     envPtr->exceptArrayPtr[range].catchOffset = CurrentOffset(envPtr);
-    if (localIndex != -1) {
+    if (resultIndex != -1) {
+	if (optsIndex != -1) {
+	    TclEmitOpcode(INST_PUSH_RETURN_OPTIONS, envPtr);
+	}
 	TclEmitOpcode(INST_PUSH_RESULT, envPtr);
-	if (localIndex <= 255) {
-	    TclEmitInstInt1(INST_STORE_SCALAR1, localIndex, envPtr);
+	if (resultIndex <= 255) {
+	    TclEmitInstInt1(INST_STORE_SCALAR1, resultIndex, envPtr);
 	} else {
-	    TclEmitInstInt4(INST_STORE_SCALAR4, localIndex, envPtr);
+	    TclEmitInstInt4(INST_STORE_SCALAR4, resultIndex, envPtr);
 	}
 	TclEmitOpcode(INST_POP, envPtr);
+	if (optsIndex != -1) {
+	    if (optsIndex <= 255) {
+		TclEmitInstInt1(INST_STORE_SCALAR1, optsIndex, envPtr);
+	    } else {
+		TclEmitInstInt4(INST_STORE_SCALAR4, optsIndex, envPtr);
+	    }
+	    TclEmitOpcode(INST_POP, envPtr);
+	}
     }
     TclEmitOpcode(INST_PUSH_RETURN_CODE, envPtr);
 
-
     /*
      * Update the target of the jump after the "no errors" code, then emit an
      * endCatch instruction at the end of the catch command.
diff --git a/generic/tclCompile.c b/generic/tclCompile.c
index f67fea6..6a7234d 100644
--- a/generic/tclCompile.c
+++ b/generic/tclCompile.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclCompile.c,v 1.85 2005/05/10 18:34:11 kennykb Exp $
+ * RCS: @(#) $Id: tclCompile.c,v 1.86 2005/06/20 21:27:10 dkf Exp $
  */
 
 #include "tclInt.h"
@@ -213,6 +213,7 @@ InstructionDesc tclInstructionTable[] = {
     {"pushReturnCode",	  1,   +1,         0,   {OPERAND_NONE}},
 	/* Push interpreter's return code (e.g. TCL_OK or TCL_ERROR) as
 	 * a new object onto the stack. */
+
     {"streq",		  1,   -1,         0,   {OPERAND_NONE}},
 	/* Str Equal:	push (stknext eq stktop) */
     {"strneq",		  1,   -1,         0,   {OPERAND_NONE}},
@@ -225,12 +226,14 @@ InstructionDesc tclInstructionTable[] = {
 	/* Str Index:	push (strindex stknext stktop) */
     {"strmatch",	  2,   -1,         1,   {OPERAND_INT1}},
 	/* Str Match:	push (strmatch stknext stktop) opnd == nocase */
+
     {"list",		  5,   INT_MIN,    1,   {OPERAND_UINT4}},
 	/* List:	push (stk1 stk2 ... stktop) */
     {"listIndex",	  1,   -1,         0,   {OPERAND_NONE}},
 	/* List Index:	push (listindex stknext stktop) */
     {"listLength",	  1,   0,          0,   {OPERAND_NONE}},
 	/* List Len:	push (listlength stktop) */
+
     {"appendScalar1",	  2,   0,          1,   {OPERAND_UINT1}},
 	/* Append scalar variable at op1<=255 in frame; value is stktop */
     {"appendScalar4",	  5,   0,          1,   {OPERAND_UINT4}},
@@ -255,10 +258,11 @@ InstructionDesc tclInstructionTable[] = {
 	/* Lappend array element; value is stktop, then elem, array names */
     {"lappendStk",	  1,   -1,         0,   {OPERAND_NONE}},
 	/* Lappend general variable; value is stktop, then unparsed name */
+
     {"lindexMulti",	  5,   INT_MIN,    1,   {OPERAND_UINT4}},
-        /* Lindex with generalized args, operand is number of stacked objs 
-	 * used: (operand-1) entries from stktop are the indices; then list 
-	 * to process. */
+        /* Lindex with generalized args, operand is number of stacked objs
+	 * used: (operand-1) entries from stktop are the indices; then list to
+	 * process. */
     {"over",		  5,   +1,         1,   {OPERAND_UINT4}},
         /* Duplicate the arg-th element from top of stack (TOS=0) */
     {"lsetList",          1,   -2,         0,   {OPERAND_NONE}},
@@ -269,37 +273,44 @@ InstructionDesc tclInstructionTable[] = {
 	 * stacked objs: stktop is old value, next is new element value, next 
 	 * come (operand-2) indices; pushes the new value.
 	 */
+
     {"return",		  9,   -1,         2,   {OPERAND_INT4, OPERAND_UINT4}},
 	/* Compiled [return], code, level are operands; options and result
 	 * are on the stack. */
+
     {"expon",		  1,   -1,	   0,	{OPERAND_NONE}},
 	/* Binary exponentiation operator: push (stknext ** stktop) */
-     /* 
-      * NOTE: the stack effects of expandStkTop and invokeExpanded
-      * are wrong - but it cannot be done right at compile time, the stack
-      * effect is only known at run time. The value for invokeExpanded
-      * is estimated better at compile time.
-      * See the comments further down in this file, where INST_INVOKE_EXPANDED 
-      * is emitted.
-      */
-     {"expandStart",       1,    0,          0,   {OPERAND_NONE}},
-         /* Start of command with {expand}ed arguments */
-     {"expandStkTop",      5,    0,          1,   {OPERAND_INT4}},
-         /* Expand the list at stacktop: push its elements on the stack */
-     {"invokeExpanded",    1,    0,          0,   {OPERAND_NONE}},
-         /* Invoke the command marked by the last 'expandStart' */
+
+    /* 
+     * NOTE: the stack effects of expandStkTop and invokeExpanded
+     * are wrong - but it cannot be done right at compile time, the stack
+     * effect is only known at run time. The value for invokeExpanded
+     * is estimated better at compile time.
+     * See the comments further down in this file, where INST_INVOKE_EXPANDED 
+     * is emitted.
+     */
+    {"expandStart",       1,    0,          0,   {OPERAND_NONE}},
+	/* Start of command with {expand}ed arguments */
+    {"expandStkTop",      5,    0,          1,   {OPERAND_INT4}},
+	/* Expand the list at stacktop: push its elements on the stack */
+    {"invokeExpanded",    1,    0,          0,   {OPERAND_NONE}},
+	/* Invoke the command marked by the last 'expandStart' */
+
     {"listIndexImm",	  5,	0,	   1,	{OPERAND_IDX4}},
 	/* List Index:	push (lindex stktop op4) */
     {"listRangeImm",	  9,	0,	   2,	{OPERAND_IDX4, OPERAND_IDX4}},
 	/* List Range:	push (lrange stktop op4 op4) */
-
-    {"startCommand",      5,    0,         1,   {OPERAND_UINT4}},
+    {"startCommand",	  5,	0,	   1,	{OPERAND_UINT4}},
         /* Start of bytecoded command: op is the length of the cmd's code */ 
 
     {"listIn",		  1,	-1,	   0,	{OPERAND_NONE}},
 	/* List containment: push [lsearch stktop stknext]>=0) */
     {"listNotIn",	  1,	-1,	   0,	{OPERAND_NONE}},
 	/* List negated containment: push [lsearch stktop stknext]<0) */
+
+    {"pushReturnOpts",	  1,	+1,	   0,	{OPERAND_NONE}}
+	/* Push the interpreter's return option dictionary as an object on the
+	 * stack. */
     {0}
 };
 
diff --git a/generic/tclCompile.h b/generic/tclCompile.h
index ab34f81..74c2091 100644
--- a/generic/tclCompile.h
+++ b/generic/tclCompile.h
@@ -8,7 +8,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclCompile.h,v 1.55 2005/05/10 18:34:27 kennykb Exp $
+ * RCS: @(#) $Id: tclCompile.h,v 1.56 2005/06/20 21:27:12 dkf Exp $
  */
 
 #ifndef _TCLCOMPILATION
@@ -34,9 +34,7 @@
  */
 
 MODULE_SCOPE int 	tclTraceCompile;
-#endif
 
-#ifdef TCL_COMPILE_DEBUG
 /*
  * Variable that controls whether execution tracing is enabled and, if so,
  * what level of tracing is desired:
@@ -49,7 +47,7 @@ MODULE_SCOPE int 	tclTraceCompile;
 
 MODULE_SCOPE int 	tclTraceExec;
 #endif
-
+
 /*
  *------------------------------------------------------------------------
  * Data structures related to compilation.
@@ -57,54 +55,55 @@ MODULE_SCOPE int 	tclTraceExec;
  */
 
 /*
- * The structure used to implement Tcl "exceptions" (exceptional returns):
- * for example, those generated in loops by the break and continue commands,
- * and those generated by scripts and caught by the catch command. This
- * ExceptionRange structure describes a range of code (e.g., a loop body),
- * the kind of exceptions (e.g., a break or continue) that might occur, and
- * the PC offsets to jump to if a matching exception does occur. Exception
- * ranges can nest so this structure includes a nesting level that is used
- * at runtime to find the closest exception range surrounding a PC. For
- * example, when a break command is executed, the ExceptionRange structure
- * for the most deeply nested loop, if any, is found and used. These
- * structures are also generated for the "next" subcommands of for loops
- * since a break there terminates the for command. This means a for command
- * actually generates two LoopInfo structures.
+ * The structure used to implement Tcl "exceptions" (exceptional returns): for
+ * example, those generated in loops by the break and continue commands, and
+ * those generated by scripts and caught by the catch command. This
+ * ExceptionRange structure describes a range of code (e.g., a loop body), the
+ * kind of exceptions (e.g., a break or continue) that might occur, and the PC
+ * offsets to jump to if a matching exception does occur. Exception ranges can
+ * nest so this structure includes a nesting level that is used at runtime to
+ * find the closest exception range surrounding a PC. For example, when a
+ * break command is executed, the ExceptionRange structure for the most deeply
+ * nested loop, if any, is found and used. These structures are also generated
+ * for the "next" subcommands of for loops since a break there terminates the
+ * for command. This means a for command actually generates two LoopInfo
+ * structures.
  */
 
 typedef enum {
-    LOOP_EXCEPTION_RANGE,	/* Exception's range is part of a loop.
-				 * Break and continue "exceptions" cause
-				 * jumps to appropriate PC offsets. */
-    CATCH_EXCEPTION_RANGE	/* Exception's range is controlled by a
-				 * catch command. Errors in the range cause
-				 * a jump to a catch PC offset. */
+    LOOP_EXCEPTION_RANGE,	/* Exception's range is part of a loop.  Break
+				 * and continue "exceptions" cause jumps to
+				 * appropriate PC offsets. */
+    CATCH_EXCEPTION_RANGE	/* Exception's range is controlled by a catch
+				 * command. Errors in the range cause a jump
+				 * to a catch PC offset. */
 } ExceptionRangeType;
 
 typedef struct ExceptionRange {
     ExceptionRangeType type;	/* The kind of ExceptionRange. */
-    int nestingLevel;		/* Static depth of the exception range.
-				 * Used to find the most deeply-nested
-				 * range surrounding a PC at runtime. */
-    int codeOffset;		/* Offset of the first instruction byte of
-				 * the code range. */
+    int nestingLevel;		/* Static depth of the exception range. Used
+				 * to find the most deeply-nested range
+				 * surrounding a PC at runtime. */
+    int codeOffset;		/* Offset of the first instruction byte of the
+				 * code range. */
     int numCodeBytes;		/* Number of bytes in the code range. */
     int breakOffset;		/* If LOOP_EXCEPTION_RANGE, the target PC
 				 * offset for a break command in the range. */
     int continueOffset;		/* If LOOP_EXCEPTION_RANGE and not -1, the
 				 * target PC offset for a continue command in
-				 * the code range. Otherwise, ignore this range
-				 * when processing a continue command. */
+				 * the code range. Otherwise, ignore this
+				 * range when processing a continue
+				 * command. */
     int catchOffset;		/* If a CATCH_EXCEPTION_RANGE, the target PC
 				 * offset for any "exception" in range. */
 } ExceptionRange;
 
 /*
  * Structure used to map between instruction pc and source locations. It
- * defines for each compiled Tcl command its code's starting offset and 
- * its source's starting offset and length. Note that the code offset
- * increases monotonically: that is, the table is sorted in code offset
- * order. The source offset is not monotonic.
+ * defines for each compiled Tcl command its code's starting offset and its
+ * source's starting offset and length. Note that the code offset increases
+ * monotonically: that is, the table is sorted in code offset order. The
+ * source offset is not monotonic.
  */
 
 typedef struct CmdLocation {
@@ -115,19 +114,18 @@ typedef struct CmdLocation {
 } CmdLocation;
 
 /*
- * CompileProcs need the ability to record information during compilation
- * that can be used by bytecode instructions during execution. The AuxData
- * structure provides this "auxiliary data" mechanism. An arbitrary number
- * of these structures can be stored in the ByteCode record (during
- * compilation they are stored in a CompileEnv structure). Each AuxData
- * record holds one word of client-specified data (often a pointer) and is
- * given an index that instructions can later use to look up the structure
- * and its data.
+ * CompileProcs need the ability to record information during compilation that
+ * can be used by bytecode instructions during execution. The AuxData
+ * structure provides this "auxiliary data" mechanism. An arbitrary number of
+ * these structures can be stored in the ByteCode record (during compilation
+ * they are stored in a CompileEnv structure). Each AuxData record holds one
+ * word of client-specified data (often a pointer) and is given an index that
+ * instructions can later use to look up the structure and its data.
  *
  * The following definitions declare the types of procedures that are called
  * to duplicate or free this auxiliary data when the containing ByteCode
- * objects are duplicated and freed. Pointers to these procedures are kept
- * in the AuxData structure.
+ * objects are duplicated and freed. Pointers to these procedures are kept in
+ * the AuxData structure.
  */
 
 typedef ClientData (AuxDataDupProc)  _ANSI_ARGS_((ClientData clientData));
@@ -136,22 +134,22 @@ typedef void       (AuxDataFreeProc) _ANSI_ARGS_((ClientData clientData));
 /*
  * We define a separate AuxDataType struct to hold type-related information
  * for the AuxData structure. This separation makes it possible for clients
- * outside of the TCL core to manipulate (in a limited fashion!) AuxData;
- * for example, it makes it possible to pickle and unpickle AuxData structs.
+ * outside of the TCL core to manipulate (in a limited fashion!) AuxData; for
+ * example, it makes it possible to pickle and unpickle AuxData structs.
  */
 
 typedef struct AuxDataType {
     char *name;			/* the name of the type. Types can be
 				 * registered and found by name */
-    AuxDataDupProc *dupProc;	/* Callback procedure to invoke when the
-				 * aux data is duplicated (e.g., when the
-				 * ByteCode structure containing the aux
-				 * data is duplicated). NULL means just
-				 * copy the source clientData bits; no
-				 * proc need be called. */
-    AuxDataFreeProc *freeProc;	/* Callback procedure to invoke when the
-				 * aux data is freed. NULL means no
-				 * proc need be called. */
+    AuxDataDupProc *dupProc;	/* Callback procedure to invoke when the aux
+				 * data is duplicated (e.g., when the ByteCode
+				 * structure containing the aux data is
+				 * duplicated). NULL means just copy the
+				 * source clientData bits; no proc need be
+				 * called. */
+    AuxDataFreeProc *freeProc;	/* Callback procedure to invoke when the aux
+				 * data is freed. NULL means no proc need be
+				 * called. */
 } AuxDataType;
 
 /*
@@ -180,70 +178,68 @@ typedef struct AuxData {
 
 typedef struct CompileEnv {
     Interp *iPtr;		/* Interpreter containing the code being
-				 * compiled. Commands and their compile
-				 * procs are specific to an interpreter so
-				 * the code emitted will depend on the
-				 * interpreter. */
+				 * compiled. Commands and their compile procs
+				 * are specific to an interpreter so the code
+				 * emitted will depend on the interpreter. */
     char *source;		/* The source string being compiled by
 				 * SetByteCodeFromAny. This pointer is not
 				 * owned by the CompileEnv and must not be
 				 * freed or changed by it. */
     int numSrcBytes;		/* Number of bytes in source. */
-    Proc *procPtr;		/* If a procedure is being compiled, a
-				 * pointer to its Proc structure; otherwise
-				 * NULL. Used to compile local variables.
-				 * Set from information provided by
-				 * ObjInterpProc in tclProc.c. */
+    Proc *procPtr;		/* If a procedure is being compiled, a pointer
+				 * to its Proc structure; otherwise NULL. Used
+				 * to compile local variables.  Set from
+				 * information provided by ObjInterpProc in
+				 * tclProc.c. */
     int numCommands;		/* Number of commands compiled. */
-    int exceptDepth;		/* Current exception range nesting level;
-				 * -1 if not in any range currently. */
-    int maxExceptDepth;		/* Max nesting level of exception ranges;
-				 * -1 if no ranges have been compiled. */
-    int maxStackDepth;		/* Maximum number of stack elements needed
-				 * to execute the code. Set by compilation
+    int exceptDepth;		/* Current exception range nesting level; -1
+				 * if not in any range currently. */
+    int maxExceptDepth;		/* Max nesting level of exception ranges; -1
+				 * if no ranges have been compiled. */
+    int maxStackDepth;		/* Maximum number of stack elements needed to
+				 * execute the code. Set by compilation
 				 * procedures before returning. */
     int currStackDepth;		/* Current stack depth. */
-    LiteralTable localLitTable;	/* Contains LiteralEntry's describing
-				 * all Tcl objects referenced by this
-				 * compiled code. Indexed by the string
-				 * representations of the literals. Used to
-				 * avoid creating duplicate objects. */
+    LiteralTable localLitTable;	/* Contains LiteralEntry's describing all Tcl
+				 * objects referenced by this compiled code.
+				 * Indexed by the string representations of
+				 * the literals. Used to avoid creating
+				 * duplicate objects. */
     unsigned char *codeStart;	/* Points to the first byte of the code. */
     unsigned char *codeNext;	/* Points to next code array byte to use. */
-    unsigned char *codeEnd;	/* Points just after the last allocated
-				 * code array byte. */
-    int mallocedCodeArray;	/* Set 1 if code array was expanded 
-				 * and codeStart points into the heap.*/
+    unsigned char *codeEnd;	/* Points just after the last allocated code
+				 * array byte. */
+    int mallocedCodeArray;	/* Set 1 if code array was expanded and
+				 * codeStart points into the heap.*/
     LiteralEntry *literalArrayPtr;
     				/* Points to start of LiteralEntry array. */
     int literalArrayNext;	/* Index of next free object array entry. */
     int literalArrayEnd;	/* Index just after last obj array entry. */
-    int mallocedLiteralArray;	/* 1 if object array was expanded and
-				 * objArray points into the heap, else 0. */
+    int mallocedLiteralArray;	/* 1 if object array was expanded and objArray
+				 * points into the heap, else 0. */
     ExceptionRange *exceptArrayPtr;
     				/* Points to start of the ExceptionRange
 				 * array. */
     int exceptArrayNext;	/* Next free ExceptionRange array index.
-				 * exceptArrayNext is the number of ranges
-				 * and (exceptArrayNext-1) is the index of
-				 * the current range's array entry. */
-    int exceptArrayEnd;		/* Index after the last ExceptionRange
-				 * array entry. */
-    int mallocedExceptArray;	/* 1 if ExceptionRange array was expanded
-				 * and exceptArrayPtr points in heap,
-				 * else 0. */
+				 * exceptArrayNext is the number of ranges and
+				 * (exceptArrayNext-1) is the index of the
+				 * current range's array entry. */
+    int exceptArrayEnd;		/* Index after the last ExceptionRange array
+				 * entry. */
+    int mallocedExceptArray;	/* 1 if ExceptionRange array was expanded and
+				 * exceptArrayPtr points in heap, else 0. */
     CmdLocation *cmdMapPtr;	/* Points to start of CmdLocation array.
-				 * numCommands is the index of the next
-				 * entry to use; (numCommands-1) is the
-				 * entry index for the last command. */
+				 * numCommands is the index of the next entry
+				 * to use; (numCommands-1) is the entry index
+				 * for the last command. */
     int cmdMapEnd;		/* Index after last CmdLocation entry. */
     int mallocedCmdMap;		/* 1 if command map array was expanded and
 				 * cmdMapPtr points in the heap, else 0. */
     AuxData *auxDataArrayPtr;	/* Points to auxiliary data array start. */
     int auxDataArrayNext;	/* Next free compile aux data array index.
-				 * auxDataArrayNext is the number of aux
-				 * data items and (auxDataArrayNext-1) is
-				 * index of current aux data array entry. */
+				 * auxDataArrayNext is the number of aux data
+				 * items and (auxDataArrayNext-1) is index of
+				 * current aux data array entry. */
     int auxDataArrayEnd;	/* Index after last aux data array entry. */
     int mallocedAuxDataArray;	/* 1 if aux data array was expanded and
 				 * auxDataArrayPtr points in heap else 0. */
@@ -260,11 +256,11 @@ typedef struct CompileEnv {
 } CompileEnv;
 
 /*
- * The structure defining the bytecode instructions resulting from compiling
- * a Tcl script. Note that this structure is variable length: a single heap
- * object is allocated to hold the ByteCode structure immediately followed
- * by the code bytes, the literal object array, the ExceptionRange array,
- * the CmdLocation map, and the compilation AuxData array.
+ * The structure defining the bytecode instructions resulting from compiling a
+ * Tcl script. Note that this structure is variable length: a single heap
+ * object is allocated to hold the ByteCode structure immediately followed by
+ * the code bytes, the literal object array, the ExceptionRange array, the
+ * CmdLocation map, and the compilation AuxData array.
  */
 
 /*
@@ -273,13 +269,12 @@ typedef struct CompileEnv {
  */
 #define TCL_BYTECODE_PRECOMPILED		0x0001
 
-
 /*
  * When a bytecode is compiled, interp or namespace resolvers have not been
  * applied yet: this is indicated by the TCL_BYTECODE_RESOLVE_VARS flag.
  */
 
-#define TCL_BYTECODE_RESOLVE_VARS               0x0002
+#define TCL_BYTECODE_RESOLVE_VARS		0x0002
 
 typedef struct ByteCode {
     TclHandle interpHandle;	/* Handle for interpreter containing the
@@ -291,25 +286,25 @@ typedef struct ByteCode {
 				 * ByteCode was compiled. Used to invalidate
 				 * code when, e.g., commands with compile
 				 * procs are redefined. */
-    Namespace *nsPtr;		/* Namespace context in which this code
-				 * was compiled. If the code is executed
-				 * if a different namespace, it must be
+    Namespace *nsPtr;		/* Namespace context in which this code was
+				 * compiled. If the code is executed if a
+				 * different namespace, it must be
 				 * recompiled. */
     int nsEpoch;		/* Value of nsPtr->resolverEpoch when this
 				 * ByteCode was compiled. Used to invalidate
 				 * code when new namespace resolution rules
 				 * are put into effect. */
-    int refCount;		/* Reference count: set 1 when created
-				 * plus 1 for each execution of the code
-				 * currently active. This structure can be
-				 * freed when refCount becomes zero. */
+    int refCount;		/* Reference count: set 1 when created plus 1
+				 * for each execution of the code currently
+				 * active. This structure can be freed when
+				 * refCount becomes zero. */
     unsigned int flags;		/* flags describing state for the codebyte.
 				 * this variable holds ORed values from the
 				 * TCL_BYTECODE_ masks defined above */
-    char *source;		/* The source string from which this
-				 * ByteCode was compiled. Note that this
-				 * pointer is not owned by the ByteCode and
-				 * must not be freed or modified by it. */
+    char *source;		/* The source string from which this ByteCode
+				 * was compiled. Note that this pointer is not
+				 * owned by the ByteCode and must not be freed
+				 * or modified by it. */
     Proc *procPtr;		/* If the ByteCode was compiled from a
 				 * procedure body, this is a pointer to its
 				 * Proc structure; otherwise NULL. This
@@ -325,71 +320,69 @@ typedef struct ByteCode {
     int numLitObjects;		/* Number of objects in literal array. */
     int numExceptRanges;	/* Number of ExceptionRange array elems. */
     int numAuxDataItems;	/* Number of AuxData items. */
-    int numCmdLocBytes;		/* Number of bytes needed for encoded
-				 * command location information. */
+    int numCmdLocBytes;		/* Number of bytes needed for encoded command
+				 * location information. */
     int maxExceptDepth;		/* Maximum nesting level of ExceptionRanges;
 				 * -1 if no ranges were compiled. */
-    int maxStackDepth;		/* Maximum number of stack elements needed
-				 * to execute the code. */
-    unsigned char *codeStart;	/* Points to the first byte of the code.
-				 * This is just after the final ByteCode
-				 * member cmdMapPtr. */
-    Tcl_Obj **objArrayPtr;	/* Points to the start of the literal
-				 * object array. This is just after the
-				 * last code byte. */
+    int maxStackDepth;		/* Maximum number of stack elements needed to
+				 * execute the code. */
+    unsigned char *codeStart;	/* Points to the first byte of the code. This
+				 * is just after the final ByteCode member
+				 * cmdMapPtr. */
+    Tcl_Obj **objArrayPtr;	/* Points to the start of the literal object
+				 * array. This is just after the last code
+				 * byte. */
     ExceptionRange *exceptArrayPtr;
     				/* Points to the start of the ExceptionRange
-				 * array. This is just after the last
-				 * object in the object array. */
+				 * array. This is just after the last object
+				 * in the object array. */
     AuxData *auxDataArrayPtr;	/* Points to the start of the auxiliary data
-				 * array. This is just after the last entry
-				 * in the ExceptionRange array. */
+				 * array. This is just after the last entry in
+				 * the ExceptionRange array. */
     unsigned char *codeDeltaStart;
-				/* Points to the first of a sequence of
-				 * bytes that encode the change in the
-				 * starting offset of each command's code.
-				 * If -127<=delta<=127, it is encoded as 1
-				 * byte, otherwise 0xFF (128) appears and
-				 * the delta is encoded by the next 4 bytes.
-				 * Code deltas are always positive. This
-				 * sequence is just after the last entry in
-				 * the AuxData array. */
+				/* Points to the first of a sequence of bytes
+				 * that encode the change in the starting
+				 * offset of each command's code. If -127 <=
+				 * delta <= 127, it is encoded as 1 byte,
+				 * otherwise 0xFF (128) appears and the delta
+				 * is encoded by the next 4 bytes. Code deltas
+				 * are always positive. This sequence is just
+				 * after the last entry in the AuxData
+				 * array. */
     unsigned char *codeLengthStart;
-				/* Points to the first of a sequence of
-				 * bytes that encode the length of each
-				 * command's code. The encoding is the same
-				 * as for code deltas. Code lengths are
-				 * always positive. This sequence is just
-				 * after the last entry in the code delta
-				 * sequence. */
+				/* Points to the first of a sequence of bytes
+				 * that encode the length of each command's
+				 * code. The encoding is the same as for code
+				 * deltas. Code lengths are always positive.
+				 * This sequence is just after the last entry
+				 * in the code delta sequence. */
     unsigned char *srcDeltaStart;
-				/* Points to the first of a sequence of
-				 * bytes that encode the change in the
-				 * starting offset of each command's source.
-				 * The encoding is the same as for code
-				 * deltas. Source deltas can be negative.
-				 * This sequence is just after the last byte
-				 * in the code length sequence. */
+				/* Points to the first of a sequence of bytes
+				 * that encode the change in the starting
+				 * offset of each command's source. The
+				 * encoding is the same as for code deltas.
+				 * Source deltas can be negative. This
+				 * sequence is just after the last byte in the
+				 * code length sequence. */
     unsigned char *srcLengthStart;
-				/* Points to the first of a sequence of
-				 * bytes that encode the length of each
-				 * command's source. The encoding is the
-				 * same as for code deltas. Source lengths
-				 * are always positive. This sequence is
-				 * just after the last byte in the source
-				 * delta sequence. */
+				/* Points to the first of a sequence of bytes
+				 * that encode the length of each command's
+				 * source. The encoding is the same as for
+				 * code deltas. Source lengths are always
+				 * positive. This sequence is just after the
+				 * last byte in the source delta sequence. */
 #ifdef TCL_COMPILE_STATS
     Tcl_Time createTime;	/* Absolute time when the ByteCode was
 				 * created. */
 #endif /* TCL_COMPILE_STATS */
 } ByteCode;
-
+
 /*
- * Opcodes for the Tcl bytecode instructions. These must correspond to
- * the entries in the table of instruction descriptions,
- * tclInstructionTable, in tclCompile.c. Also, the order and number of
- * the expression opcodes (e.g., INST_LOR) must match the entries in
- * the array operatorStrings in tclExecute.c.
+ * Opcodes for the Tcl bytecode instructions. These must correspond to the
+ * entries in the table of instruction descriptions, tclInstructionTable, in
+ * tclCompile.c. Also, the order and number of the expression opcodes (e.g.,
+ * INST_LOR) must match the entries in the array operatorStrings in
+ * tclExecute.c.
  */
 
 /* Opcodes 0 to 9 */
@@ -533,9 +526,9 @@ typedef struct ByteCode {
 
 /* TIP #157 - {expand}... language syntax support. */
 
-#define INST_EXPAND_START             100
-#define INST_EXPAND_STKTOP            101
-#define INST_INVOKE_EXPANDED          102
+#define INST_EXPAND_START		100
+#define INST_EXPAND_STKTOP		101
+#define INST_INVOKE_EXPANDED		102
 
 /*
  * TIP #57 - 'lassign' command.  Code generation requires immediate
@@ -545,21 +538,23 @@ typedef struct ByteCode {
 #define INST_LIST_INDEX_IMM		103
 #define INST_LIST_RANGE_IMM		104
 
-#define INST_START_CMD                  105
+#define INST_START_CMD			105
 
 #define INST_LIST_IN			106
 #define INST_LIST_NOT_IN		107
 
-/* The last opcode */
-#define LAST_INST_OPCODE		107
+#define INST_PUSH_RETURN_OPTIONS	108
 
+/* The last opcode */
+#define LAST_INST_OPCODE		108
+
 /*
- * Table describing the Tcl bytecode instructions: their name (for
- * displaying code), total number of code bytes required (including
- * operand bytes), and a description of the type of each operand.
- * These operand types include signed and unsigned integers of length
- * one and four bytes. The unsigned integers are used for indexes or
- * for, e.g., the count of objects to push in a "push" instruction.
+ * Table describing the Tcl bytecode instructions: their name (for displaying
+ * code), total number of code bytes required (including operand bytes), and a
+ * description of the type of each operand. These operand types include signed
+ * and unsigned integers of length one and four bytes. The unsigned integers
+ * are used for indexes or for, e.g., the count of objects to push in a "push"
+ * instruction.
  */
 
 #define MAX_INSTRUCTION_OPERANDS 2
@@ -577,11 +572,11 @@ typedef enum InstOperandType {
 typedef struct InstructionDesc {
     char *name;			/* Name of instruction. */
     int numBytes;		/* Total number of bytes for instruction. */
-    int stackEffect;		/* The worst-case balance stack effect of the 
-				 * instruction, used for stack requirements 
+    int stackEffect;		/* The worst-case balance stack effect of the
+				 * instruction, used for stack requirements
 				 * computations. The value INT_MIN signals
-				 * that the instruction's worst case effect
-				 * is (1-opnd1).
+				 * that the instruction's worst case effect is
+				 * (1-opnd1).
 				 */
     int numOperands;		/* Number of operands. */
     InstOperandType opTypes[MAX_INSTRUCTION_OPERANDS];
@@ -592,15 +587,15 @@ MODULE_SCOPE InstructionDesc tclInstructionTable[];
 
 /*
  * Compilation of some Tcl constructs such as if commands and the logical or
- * (||) and logical and (&&) operators in expressions requires the
- * generation of forward jumps. Since the PC target of these jumps isn't
- * known when the jumps are emitted, we record the offset of each jump in an
- * array of JumpFixup structures. There is one array for each sequence of
- * jumps to one target PC. When we learn the target PC, we update the jumps
- * with the correct distance. Also, if the distance is too great (> 127
- * bytes), we replace the single-byte jump with a four byte jump
- * instruction, move the instructions after the jump down, and update the
- * code offsets for any commands between the jump and the target.
+ * (||) and logical and (&&) operators in expressions requires the generation
+ * of forward jumps. Since the PC target of these jumps isn't known when the
+ * jumps are emitted, we record the offset of each jump in an array of
+ * JumpFixup structures. There is one array for each sequence of jumps to one
+ * target PC. When we learn the target PC, we update the jumps with the
+ * correct distance. Also, if the distance is too great (> 127 bytes), we
+ * replace the single-byte jump with a four byte jump instruction, move the
+ * instructions after the jump down, and update the code offsets for any
+ * commands between the jump and the target.
  */
 
 typedef enum {
@@ -619,9 +614,9 @@ typedef struct JumpFixup {
 				 * commands if the two-byte jump at jumpPc
 				 * must be replaced with a five-byte one. */
     int exceptIndex;		/* Index of the first range entry in the
-				 * ExceptionRange array after the current
-				 * one. This field is used to adjust the
-				 * code offsets in subsequent ExceptionRange
+				 * ExceptionRange array after the current one.
+				 * This field is used to adjust the code
+				 * offsets in subsequent ExceptionRange
 				 * records when a jump is grown from 2 bytes
 				 * to 5 bytes. */
 } JumpFixup;
@@ -639,21 +634,21 @@ typedef struct JumpFixupArray {
 } JumpFixupArray;
 
 /*
- * The structure describing one variable list of a foreach command. Note
- * that only foreach commands inside procedure bodies are compiled inline so
- * a ForeachVarList structure always describes local variables. Furthermore,
+ * The structure describing one variable list of a foreach command. Note that
+ * only foreach commands inside procedure bodies are compiled inline so a
+ * ForeachVarList structure always describes local variables. Furthermore,
  * only scalar variables are supported for inline-compiled foreach loops.
  */
 
 typedef struct ForeachVarList {
     int numVars;		/* The number of variables in the list. */
     int varIndexes[1];		/* An array of the indexes ("slot numbers")
-				 * for each variable in the procedure's
-				 * array of local variables. Only scalar
-				 * variables are supported. The actual
-				 * size of this field will be large enough
-				 * to numVars indexes. THIS MUST BE THE
-				 * LAST FIELD IN THE STRUCTURE! */
+				 * for each variable in the procedure's array
+				 * of local variables. Only scalar variables
+				 * are supported. The actual size of this
+				 * field will be large enough to numVars
+				 * indexes. THIS MUST BE THE LAST FIELD IN THE
+				 * STRUCTURE! */
 } ForeachVarList;
 
 /*
@@ -665,22 +660,21 @@ typedef struct ForeachVarList {
 typedef struct ForeachInfo {
     int numLists;		/* The number of both the variable and value
 				 * lists of the foreach command. */
-    int firstValueTemp;		/* Index of the first temp var in a proc
-				 * frame used to point to a value list. */
-    int loopCtTemp;		/* Index of temp var in a proc frame
-				 * holding the loop's iteration count. Used
-				 * to determine next value list element to
-				 * assign each loop var. */
+    int firstValueTemp;		/* Index of the first temp var in a proc frame
+				 * used to point to a value list. */
+    int loopCtTemp;		/* Index of temp var in a proc frame holding
+				 * the loop's iteration count. Used to
+				 * determine next value list element to assign
+				 * each loop var. */
     ForeachVarList *varLists[1];/* An array of pointers to ForeachVarList
 				 * structures describing each var list. The
 				 * actual size of this field will be large
-				 * enough to numVars indexes. THIS MUST BE
-				 * THE LAST FIELD IN THE STRUCTURE! */
+				 * enough to numVars indexes. THIS MUST BE THE
+				 * LAST FIELD IN THE STRUCTURE! */
 } ForeachInfo;
 
 MODULE_SCOPE AuxDataType		tclForeachInfoType;
-
-
+
 /*
  *----------------------------------------------------------------
  * Procedures exported by tclBasic.c to be used within the engine.
@@ -702,7 +696,7 @@ MODULE_SCOPE int	TclEvalObjvInternal _ANSI_ARGS_((Tcl_Interp *interp,
  *
 MODULE_SCOPE int	TclCompEvalObj _ANSI_ARGS_((Tcl_Interp *interp,
 			    Tcl_Obj *objPtr));
-*/
+ */
 
 /*
  *----------------------------------------------------------------
@@ -759,8 +753,7 @@ MODULE_SCOPE void	TclInitByteCodeObj _ANSI_ARGS_((Tcl_Obj *objPtr,
 			    CompileEnv *envPtr));
 MODULE_SCOPE void	TclInitCompilation _ANSI_ARGS_((void));
 MODULE_SCOPE void	TclInitCompileEnv _ANSI_ARGS_((Tcl_Interp *interp,
-			    CompileEnv *envPtr, char *string,
-			    int numBytes));
+			    CompileEnv *envPtr, char *string, int numBytes));
 MODULE_SCOPE void	TclInitJumpFixupArray _ANSI_ARGS_((
 			    JumpFixupArray *fixupArrayPtr));
 MODULE_SCOPE void	TclInitLiteralTable _ANSI_ARGS_((
@@ -780,7 +773,8 @@ MODULE_SCOPE void	TclPrintObject _ANSI_ARGS_((FILE *outFile,
 			    Tcl_Obj *objPtr, int maxChars));
 MODULE_SCOPE void	TclPrintSource _ANSI_ARGS_((FILE *outFile,
 			    CONST char *string, int maxChars));
-MODULE_SCOPE void	TclRegisterAuxDataType _ANSI_ARGS_((AuxDataType *typePtr));
+MODULE_SCOPE void	TclRegisterAuxDataType _ANSI_ARGS_((
+			    AuxDataType *typePtr));
 MODULE_SCOPE int	TclRegisterLiteral _ANSI_ARGS_((CompileEnv *envPtr,
 			    char *bytes, int length, int flags));
 MODULE_SCOPE void	TclReleaseLiteral _ANSI_ARGS_((Tcl_Interp *interp,
@@ -793,11 +787,11 @@ MODULE_SCOPE void	TclVerifyGlobalLiteralTable _ANSI_ARGS_((
 MODULE_SCOPE void	TclVerifyLocalLiteralTable _ANSI_ARGS_((
 			    CompileEnv *envPtr));
 #endif
-MODULE_SCOPE int	TclCompileVariableCmd _ANSI_ARGS_((
-			    Tcl_Interp *interp, Tcl_Parse *parsePtr, CompileEnv *envPtr));
+MODULE_SCOPE int	TclCompileVariableCmd _ANSI_ARGS_((Tcl_Interp *interp,
+			    Tcl_Parse *parsePtr, CompileEnv *envPtr));
 MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 			    Tcl_Token *tokenPtr, Tcl_Obj *valuePtr));
-
+
 /*
  *----------------------------------------------------------------
  * Macros and flag values used by Tcl bytecode compilation and execution
@@ -808,31 +802,34 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 #define LITERAL_ON_HEAP    0x01
 #define LITERAL_NS_SCOPE   0x02
 /*
- * Form of TclRegisterLiteral with onHeap == 0.
- * In that case, it is safe to cast away CONSTness, and it
- * is cleanest to do that here, all in one place.
+ * Form of TclRegisterLiteral with onHeap == 0. In that case, it is safe to
+ * cast away CONSTness, and it is cleanest to do that here, all in one place.
+ *
+ * int TclRegisterNewLiteral(CompileEnv *envPtr, const char *bytes,
+ *			     int length);
  */
 
 #define TclRegisterNewLiteral(envPtr, bytes, length) \
-	TclRegisterLiteral(envPtr, (char *)(bytes), length, \
-                /*flags*/ 0)
+	TclRegisterLiteral(envPtr, (char *)(bytes), length, /*flags*/ 0)
 
 /*
- * Form of TclRegisterNSLiteral with onHeap == 0.
- * In that case, it is safe to cast away CONSTness, and it
- * is cleanest to do that here, all in one place.
+ * Form of TclRegisterNSLiteral with onHeap == 0.  In that case, it is safe to
+ * cast away CONSTness, and it is cleanest to do that here, all in one place.
+ *
+ * int TclRegisterNewNSLiteral(CompileEnv *envPtr, const char *bytes,
+ *			       int length);
  */
 
 #define TclRegisterNewNSLiteral(envPtr, bytes, length) \
 	TclRegisterLiteral(envPtr, (char *)(bytes), length, \
-                /*flags*/ LITERAL_NS_SCOPE)
-
+		/*flags*/ LITERAL_NS_SCOPE)
 
 /*
- * Macro used to manually adjust the stack requirements; used
- * in cases where the stack effect cannot be computed from
- * the opcode and its operands, but is still known at
- * compile time.
+ * Macro used to manually adjust the stack requirements; used in cases where
+ * the stack effect cannot be computed from the opcode and its operands, but
+ * is still known at compile time.
+ *
+ * void TclAdjustStackDepth(int delta, CompileEnv *envPtr);
  */
 
 #define TclAdjustStackDepth(delta, envPtr) \
@@ -844,12 +841,13 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
     (envPtr)->currStackDepth += (delta)
 
 /*
- * Macro used to update the stack requirements.
- * It is called by the macros TclEmitOpCode, TclEmitInst1 and
- * TclEmitInst4.
- * Remark that the very last instruction of a bytecode always
- * reduces the stack level: INST_DONE or INST_POP, so that the 
- * maxStackdepth is always updated.
+ * Macro used to update the stack requirements.  It is called by the macros
+ * TclEmitOpCode, TclEmitInst1 and TclEmitInst4.
+ * Remark that the very last instruction of a bytecode always reduces the
+ * stack level: INST_DONE or INST_POP, so that the maxStackdepth is always
+ * updated.
+ *
+ * void TclUpdateStackReqs(unsigned char op, int i, CompileEnv *envPtr);
  */
 
 #define TclUpdateStackReqs(op, i, envPtr) \
@@ -859,16 +857,15 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 	    if (delta == INT_MIN) {\
 		delta = 1 - (i);\
 	    }\
-            TclAdjustStackDepth(delta, envPtr);\
-        }\
+	    TclAdjustStackDepth(delta, envPtr);\
+	}\
     }
 
 /*
- * Macro to emit an opcode byte into a CompileEnv's code array.
- * The ANSI C "prototype" for this macro is:
+ * Macro to emit an opcode byte into a CompileEnv's code array.  The ANSI C
+ * "prototype" for this macro is:
  *
- * MODULE_SCOPE void	TclEmitOpcode _ANSI_ARGS_((unsigned char op,
- *		    CompileEnv *envPtr));
+ * void TclEmitOpcode(unsigned char op, CompileEnv *envPtr);
  */
 
 #define TclEmitOpcode(op, envPtr) \
@@ -878,11 +875,11 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
     TclUpdateStackReqs(op, 0, envPtr)
 
 /*
- * Macros to emit an integer operand.
- * The ANSI C "prototype" for these macros are:
+ * Macros to emit an integer operand.  The ANSI C "prototype" for these macros
+ * are:
  *
- * MODULE_SCOPE void	TclEmitInt1 _ANSI_ARGS_((int i, CompileEnv *envPtr));
- * MODULE_SCOPE void	TclEmitInt4 _ANSI_ARGS_((int i, CompileEnv *envPtr));
+ * void TclEmitInt1(int i, CompileEnv *envPtr);
+ * void TclEmitInt4(int i, CompileEnv *envPtr);
  */
 
 #define TclEmitInt1(i, envPtr) \
@@ -906,16 +903,13 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 /*
  * Macros to emit an instruction with signed or unsigned integer operands.
  * Four byte integers are stored in "big-endian" order with the high order
- * byte stored at the lowest address.
- * The ANSI C "prototypes" for these macros are:
+ * byte stored at the lowest address.  The ANSI C "prototypes" for these
+ * macros are:
  *
- * MODULE_SCOPE void	TclEmitInstInt1 _ANSI_ARGS_((unsigned char op, int i, 
- *		    CompileEnv *envPtr));
- * MODULE_SCOPE void	TclEmitInstInt4 _ANSI_ARGS_((unsigned char op, int i, 
- *		    CompileEnv *envPtr));
+ * void TclEmitInstInt1(unsigned char op, int i, CompileEnv *envPtr);
+ * void TclEmitInstInt4(unsigned char op, int i, CompileEnv *envPtr);
  */
 
-
 #define TclEmitInstInt1(op, i, envPtr) \
     if (((envPtr)->codeNext + 2) > (envPtr)->codeEnd) { \
 	TclExpandCodeArray(envPtr); \
@@ -941,11 +935,11 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 
 /*
  * Macro to push a Tcl object onto the Tcl evaluation stack. It emits the
- * object's one or four byte array index into the CompileEnv's code
- * array. These support, respectively, a maximum of 256 (2**8) and 2**32
- * objects in a CompileEnv. The ANSI C "prototype" for this macro is:
+ * object's one or four byte array index into the CompileEnv's code array.
+ * These support, respectively, a maximum of 256 (2**8) and 2**32 objects in a
+ * CompileEnv. The ANSI C "prototype" for this macro is:
  *
- * MODULE_SCOPE void	TclEmitPush _ANSI_ARGS_((int objIndex, CompileEnv *envPtr));
+ * void	TclEmitPush(int objIndex, CompileEnv *envPtr);
  */
 
 #define TclEmitPush(objIndex, envPtr) \
@@ -959,12 +953,12 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
     }
 
 /*
- * Macros to update a (signed or unsigned) integer starting at a pointer.
- * The two variants depend on the number of bytes. The ANSI C "prototypes"
- * for these macros are:
+ * Macros to update a (signed or unsigned) integer starting at a pointer.  The
+ * two variants depend on the number of bytes. The ANSI C "prototypes" for
+ * these macros are:
  *
- * MODULE_SCOPE void	TclStoreInt1AtPtr _ANSI_ARGS_((int i, unsigned char *p));
- * MODULE_SCOPE void	TclStoreInt4AtPtr _ANSI_ARGS_((int i, unsigned char *p));
+ * void TclStoreInt1AtPtr(int i, unsigned char *p);
+ * void TclStoreInt4AtPtr(int i, unsigned char *p);
  */
 
 #define TclStoreInt1AtPtr(i, p) \
@@ -977,14 +971,12 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
     *(p+3) = (unsigned char) ((unsigned int) (i)      )
 
 /*
- * Macros to update instructions at a particular pc with a new op code
- * and a (signed or unsigned) int operand. The ANSI C "prototypes" for
- * these macros are:
+ * Macros to update instructions at a particular pc with a new op code and a
+ * (signed or unsigned) int operand. The ANSI C "prototypes" for these macros
+ * are:
  *
- * MODULE_SCOPE void	TclUpdateInstInt1AtPc _ANSI_ARGS_((unsigned char op, int i,
- *		    unsigned char *pc));
- * MODULE_SCOPE void	TclUpdateInstInt4AtPc _ANSI_ARGS_((unsigned char op, int i,
- *		    unsigned char *pc));
+ * void TclUpdateInstInt1AtPc(unsigned char op, int i, unsigned char *pc);
+ * void TclUpdateInstInt4AtPc(unsigned char op, int i, unsigned char *pc);
  */
 
 #define TclUpdateInstInt1AtPc(op, i, pc) \
@@ -996,12 +988,12 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
     TclStoreInt4AtPtr((i), ((pc)+1))
 
 /*
- * Macro to fix up a forward jump to point to the current
- * code-generation position in the bytecode being created (the most
- * common case). The ANSI C "prototypes" for this macro is:
+ * Macro to fix up a forward jump to point to the current code-generation
+ * position in the bytecode being created (the most common case). The ANSI C
+ * "prototypes" for this macro is:
  *
- * MODULE_SCOPE int	TclFixupForwardJumpToHere _ANSI_ARGS_((CompileEnv *envPtr,
- *		    JumpFixup *fixupPtr, int threshold));
+ * int TclFixupForwardJumpToHere(CompileEnv *envPtr, JumpFixup *fixupPtr,
+ *				 int threshold);
  */
 
 #define TclFixupForwardJumpToHere(envPtr, fixupPtr, threshold) \
@@ -1011,23 +1003,22 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 
 /*
  * Macros to get a signed integer (GET_INT{1,2}) or an unsigned int
- * (GET_UINT{1,2}) from a pointer. There are two variants for each
- * return type that depend on the number of bytes fetched.
- * The ANSI C "prototypes" for these macros are:
+ * (GET_UINT{1,2}) from a pointer. There are two variants for each return type
+ * that depend on the number of bytes fetched.  The ANSI C "prototypes" for
+ * these macros are:
  *
- * MODULE_SCOPE int		TclGetInt1AtPtr  _ANSI_ARGS_((unsigned char *p));
- * MODULE_SCOPE int		TclGetInt4AtPtr  _ANSI_ARGS_((unsigned char *p));
- * MODULE_SCOPE unsigned int	TclGetUInt1AtPtr _ANSI_ARGS_((unsigned char *p));
- * MODULE_SCOPE unsigned int	TclGetUInt4AtPtr _ANSI_ARGS_((unsigned char *p));
+ * int TclGetInt1AtPtr(unsigned char *p);
+ * int TclGetInt4AtPtr(unsigned char *p);
+ * unsigned int TclGetUInt1AtPtr(unsigned char *p);
+ * unsigned int TclGetUInt4AtPtr(unsigned char *p);
  */
 
 /*
- * The TclGetInt1AtPtr macro is tricky because we want to do sign
- * extension on the 1-byte value. Unfortunately the "char" type isn't
- * signed on all platforms so sign-extension doesn't always happen
- * automatically. Sometimes we can explicitly declare the pointer to be
- * signed, but other times we have to explicitly sign-extend the value
- * in software.
+ * The TclGetInt1AtPtr macro is tricky because we want to do sign extension on
+ * the 1-byte value. Unfortunately the "char" type isn't signed on all
+ * platforms so sign-extension doesn't always happen automatically. Sometimes
+ * we can explicitly declare the pointer to be signed, but other times we have
+ * to explicitly sign-extend the value in software.
  */
 
 #ifndef __CHAR_UNSIGNED__
@@ -1035,10 +1026,10 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 #else
 #   ifdef HAVE_SIGNED_CHAR
 #	define TclGetInt1AtPtr(p) ((int) *((signed char *) p))
-#    else
+#   else
 #	define TclGetInt1AtPtr(p) (((int) *((char *) p)) \
 		| ((*(p) & 0200) ? (-256) : 0))
-#    endif
+#   endif
 #endif
 
 #define TclGetInt4AtPtr(p) (((int) TclGetInt1AtPtr(p) << 24) | \
@@ -1053,11 +1044,11 @@ MODULE_SCOPE int	TclWordKnownAtCompileTime _ANSI_ARGS_((
 					    (*((p)+3)))
 
 /*
- * Macros used to compute the minimum and maximum of two integers.
- * The ANSI C "prototypes" for these macros are:
+ * Macros used to compute the minimum and maximum of two integers.  The ANSI C
+ * "prototypes" for these macros are:
  *
- * MODULE_SCOPE int  TclMin _ANSI_ARGS_((int i, int j));
- * MODULE_SCOPE int  TclMax _ANSI_ARGS_((int i, int j));
+ * int TclMin(int i, int j);
+ * int TclMax(int i, int j);
  */
 
 #define TclMin(i, j)   ((((int) i) < ((int) j))? (i) : (j))
diff --git a/generic/tclExecute.c b/generic/tclExecute.c
index c86be8f..9277a70 100644
--- a/generic/tclExecute.c
+++ b/generic/tclExecute.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclExecute.c,v 1.190 2005/05/18 20:55:04 dgp Exp $
+ * RCS: @(#) $Id: tclExecute.c,v 1.191 2005/06/20 21:27:13 dkf Exp $
  */
 
 #include "tclInt.h"
@@ -1085,8 +1085,8 @@ TclExecuteByteCode(interp, codePtr)
     register Tcl_Obj **tosPtr;  /* Cached pointer to top of evaluation stack. */
     register unsigned char *pc = codePtr->codeStart;
 				/* The current program counter. */
-    int instructionCount = 0;	/* Counter that is used to work out
-				 * when to call Tcl_AsyncReady() */
+    int instructionCount = 0;	/* Counter that is used to work out when to
+				 * call Tcl_AsyncReady() */
     Tcl_Obj *expandNestList = NULL;
     int checkInterp = 0;        /* Indicates when a check of interp readyness
 				 * is necessary. Set by DECACHE_STACK_INFO() */
@@ -1101,8 +1101,8 @@ TclExecuteByteCode(interp, codePtr)
 
     
     /*
-     * Result variable - needed only when going to checkForcatch or
-     * other error handlers; also used as local in some opcodes.
+     * Result variable - needed only when going to checkForcatch or other
+     * error handlers; also used as local in some opcodes.
      */
 
     int result = TCL_OK;	/* Return code returned after execution. */
@@ -1247,25 +1247,28 @@ TclExecuteByteCode(interp, codePtr)
 #endif
 
     /*
-     * Check for asynchronous handlers [Bug 746722]; we
-     * do the check every ASYNC_CHECK_COUNT_MASK instruction,
-     * of the form (2**n-1).
+     * Check for asynchronous handlers [Bug 746722]; we do the check every
+     * ASYNC_CHECK_COUNT_MASK instruction, of the form (2**n-1).
      */
 
     if ((instructionCount++ & ASYNC_CHECK_COUNT_MASK) == 0) {
 	if (Tcl_AsyncReady()) {
+	    int localResult;
 	    DECACHE_STACK_INFO();
-	    result = Tcl_AsyncInvoke(interp, result);
+	    localResult = Tcl_AsyncInvoke(interp, result);
 	    CACHE_STACK_INFO();
-	    if (result == TCL_ERROR) {
+	    if (localResult == TCL_ERROR) {
+		result = localResult;
 		goto checkForCatch;
 	    }
 	}
 	if (Tcl_LimitReady(interp)) {
+	    int localResult;
 	    DECACHE_STACK_INFO();
-	    result = Tcl_LimitCheck(interp);
+	    localResult = Tcl_LimitCheck(interp);
 	    CACHE_STACK_INFO();
-	    if (result == TCL_ERROR) {
+	    if (localResult == TCL_ERROR) {
+		result = localResult;
 		goto checkForCatch;
 	    }
 	}
@@ -1420,177 +1423,166 @@ TclExecuteByteCode(interp, codePtr)
 	TRACE_WITH_OBJ(("=> "), objResultPtr);
 	NEXT_INST_F(1, 0, 1);
 
-    case INST_OVER:
-        {
-	    int opnd;
-	    
-	    opnd = TclGetUInt4AtPtr(pc+1);
-	    objResultPtr = *(tosPtr - opnd);
-	    TRACE_WITH_OBJ(("=> "), objResultPtr);
-	    NEXT_INST_F(5, 0, 1);
-	}
+    case INST_OVER: {
+	int opnd;
 
-    case INST_CONCAT1:
-	{
-	    int opnd, length, appendLen = 0;
-	    char *bytes, *p;		
-	    Tcl_Obj **currPtr;
-	    
-	    opnd = TclGetUInt1AtPtr(pc+1);
+	opnd = TclGetUInt4AtPtr(pc+1);
+	objResultPtr = *(tosPtr - opnd);
+	TRACE_WITH_OBJ(("=> "), objResultPtr);
+	NEXT_INST_F(5, 0, 1);
+    }
 
-	    /*
-	     * Compute the length to be appended.
-	     */
-	    
-	    for (currPtr = tosPtr - (opnd-2); currPtr <= tosPtr; 
-		     currPtr++) {
-		bytes = Tcl_GetStringFromObj(*currPtr, &length);
-		if (bytes != NULL) {
-		    appendLen += length;
-		}
-	    }
+    case INST_CONCAT1: {
+	int opnd, length, appendLen = 0;
+	char *bytes, *p;		
+	Tcl_Obj **currPtr;
 
-	    /*
-	     * If nothing is to be appended, just return the first
-	     * object by dropping all the others from the stack; this
-	     * saves both the computation and copy of the string rep
-	     * of the first object, enabling the fast '$x[set x {}]'
-	     * idiom for 'K $x [set x{}]'.
-	     */
+	opnd = TclGetUInt1AtPtr(pc+1);
 
-	    if (appendLen == 0) {
-		TRACE_WITH_OBJ(("%u => ", opnd), objResultPtr);
-		NEXT_INST_V(2, (opnd-1), 0);
+	/*
+	 * Compute the length to be appended.
+	 */
+
+	for (currPtr = tosPtr - (opnd-2); currPtr <= tosPtr; currPtr++) {
+	    bytes = Tcl_GetStringFromObj(*currPtr, &length);
+	    if (bytes != NULL) {
+		appendLen += length;
 	    }
+	}
 
-	    /*
-	     * If the first object is shared, we need a new obj for
-	     * the result; otherwise, we can reuse the first object.
-	     * In any case, make sure it has enough room to accomodate
-	     * all the concatenated bytes. Note that if it is unshared
-	     * its bytes are already copied by Tcl_SetObjectLength, so
-	     * that we set the loop parameters to avoid copying them
-	     * again: p points to the end of the already copied bytes,
-	     * currPtr to the second object.
-	     */
-	    
-	    objResultPtr = *(tosPtr-(opnd-1));
-	    bytes = Tcl_GetStringFromObj(objResultPtr, &length);
+	/*
+	 * If nothing is to be appended, just return the first object by
+	 * dropping all the others from the stack; this saves both the
+	 * computation and copy of the string rep of the first object,
+	 * enabling the fast '$x[set x {}]' idiom for 'K $x [set x{}]'.
+	 */
+
+	if (appendLen == 0) {
+	    TRACE_WITH_OBJ(("%u => ", opnd), objResultPtr);
+	    NEXT_INST_V(2, (opnd-1), 0);
+	}
+
+	/*
+	 * If the first object is shared, we need a new obj for the result;
+	 * otherwise, we can reuse the first object.  In any case, make sure
+	 * it has enough room to accomodate all the concatenated bytes. Note
+	 * that if it is unshared its bytes are already copied by
+	 * Tcl_SetObjectLength, so that we set the loop parameters to avoid
+	 * copying them again: p points to the end of the already copied
+	 * bytes, currPtr to the second object.
+	 */
+
+	objResultPtr = *(tosPtr-(opnd-1));
+	bytes = Tcl_GetStringFromObj(objResultPtr, &length);
 #if !TCL_COMPILE_DEBUG
-	    if (!Tcl_IsShared(objResultPtr)) {
-		Tcl_SetObjLength(objResultPtr, (length + appendLen));
-		p = TclGetString(objResultPtr) + length;
-		currPtr = tosPtr - (opnd - 2);
-	    } else {
+	if (!Tcl_IsShared(objResultPtr)) {
+	    Tcl_SetObjLength(objResultPtr, (length + appendLen));
+	    p = TclGetString(objResultPtr) + length;
+	    currPtr = tosPtr - (opnd - 2);
+	} else {
 #endif
-		p = (char *) ckalloc((unsigned) (length + appendLen + 1));
-		TclNewObj(objResultPtr);
-		objResultPtr->bytes = p;
-		objResultPtr->length = length + appendLen;
-		currPtr = tosPtr - (opnd - 1);
+	    p = (char *) ckalloc((unsigned) (length + appendLen + 1));
+	    TclNewObj(objResultPtr);
+	    objResultPtr->bytes = p;
+	    objResultPtr->length = length + appendLen;
+	    currPtr = tosPtr - (opnd - 1);
 #if !TCL_COMPILE_DEBUG
-	    } 
+	} 
 #endif
 
-	    /*
-	     * Append the remaining characters.
-	     */
+	/*
+	 * Append the remaining characters.
+	 */
 
-	    for (; currPtr <= tosPtr; currPtr++) {
-		bytes = Tcl_GetStringFromObj(*currPtr, &length);
-		if (bytes != NULL) {
-		    memcpy((VOID *) p, (VOID *) bytes,
-			    (size_t) length);
-		    p += length;
-		}
+	for (; currPtr <= tosPtr; currPtr++) {
+	    bytes = Tcl_GetStringFromObj(*currPtr, &length);
+	    if (bytes != NULL) {
+		memcpy((VOID *) p, (VOID *) bytes, (size_t) length);
+		p += length;
 	    }
-	    *p = '\0';
-		
-	    TRACE_WITH_OBJ(("%u => ", opnd), objResultPtr);
-	    NEXT_INST_V(2, opnd, 1);
 	}
+	*p = '\0';
 
-    case INST_EXPAND_START:
+	TRACE_WITH_OBJ(("%u => ", opnd), objResultPtr);
+	NEXT_INST_V(2, opnd, 1);
+    }
+
+    case INST_EXPAND_START: {
 	/*
-	 * Push an element to the expandNestList. This records
-	 * the current tosPtr - i.e., the point in the stack
-	 * where the expanded command starts.
+	 * Push an element to the expandNestList. This records the current
+	 * tosPtr - i.e., the point in the stack where the expanded command
+	 * starts.
 	 *
-	 * Use a Tcl_Obj as linked list element; slight mem waste,
-	 * but faster allocation than ckalloc. This also abuses
-	 * the Tcl_Obj structure, as we do not define a special
-	 * tclObjType for it. It is not dangerous as the obj is
-	 * never passed anywhere, so that all manipulations are
-	 * performed here and in INST_INVOKE_EXPANDED (in case of
-	 * an expansion error, also in INST_EXPAND_STKTOP).
+	 * Use a Tcl_Obj as linked list element; slight mem waste, but faster
+	 * allocation than ckalloc. This also abuses the Tcl_Obj structure, as
+	 * we do not define a special tclObjType for it. It is not dangerous
+	 * as the obj is never passed anywhere, so that all manipulations are
+	 * performed here and in INST_INVOKE_EXPANDED (in case of an expansion
+	 * error, also in INST_EXPAND_STKTOP).
 	 */
 
-        {
-	    Tcl_Obj *objPtr;
+	Tcl_Obj *objPtr;
 
-	    TclNewObj(objPtr);
-	    objPtr->internalRep.twoPtrValue.ptr1 = (VOID *) (tosPtr - eePtr->stackPtr);
-	    objPtr->internalRep.twoPtrValue.ptr2 = (VOID *) expandNestList;
-	    expandNestList = objPtr;
-	    NEXT_INST_F(1, 0, 0);
-	}
+	TclNewObj(objPtr);
+	objPtr->internalRep.twoPtrValue.ptr1 = (VOID *)
+		(tosPtr - eePtr->stackPtr);
+	objPtr->internalRep.twoPtrValue.ptr2 = (VOID *) expandNestList;
+	expandNestList = objPtr;
+	NEXT_INST_F(1, 0, 0);
+    }
 
-    case INST_EXPAND_STKTOP:
-	{  
-	    int objc, length, i;
-	    Tcl_Obj **objv, *valuePtr, *objPtr;
+    case INST_EXPAND_STKTOP: {  
+	int objc, length, i;
+	Tcl_Obj **objv, *valuePtr, *objPtr;
 
-	    /*
-	     * Make sure that the element at stackTop is a list; if not,
-	     * remove the element from the expand link list and leave.
-	     */
-	    
+	/*
+	 * Make sure that the element at stackTop is a list; if not, remove
+	 * the element from the expand link list and leave.
+	 */
 
-	    valuePtr = *tosPtr;
-	    result = Tcl_ListObjGetElements(interp, valuePtr, &objc, &objv);
-	    if (result != TCL_OK) {
-		TRACE_WITH_OBJ(("%.30s => ERROR: ", O2S(valuePtr)),
-	        	Tcl_GetObjResult(interp));
-		objPtr = expandNestList;
-		expandNestList = (Tcl_Obj *) objPtr->internalRep.twoPtrValue.ptr2;
-		TclDecrRefCount(objPtr);
-		goto checkForCatch;
-	    }
-	    tosPtr--;
+	valuePtr = *tosPtr;
+	if (Tcl_ListObjGetElements(interp, valuePtr, &objc, &objv) != TCL_OK) {
+	    TRACE_WITH_OBJ(("%.30s => ERROR: ", O2S(valuePtr)),
+		    Tcl_GetObjResult(interp));
+	    objPtr = expandNestList;
+	    expandNestList = (Tcl_Obj *) objPtr->internalRep.twoPtrValue.ptr2;
+	    TclDecrRefCount(objPtr);
+	    goto checkForCatch;
+	}
+	tosPtr--;
 
-	    /*
-	     * Make sure there is enough room in the stack to expand
-	     * this list *and* process the rest of the command (at least
-	     * up to the next argument expansion or command end).
-	     * The operand is the current stack depth, as seen by the 
-	     * compiler.
-	     */ 
-
-	    length = objc + codePtr->maxStackDepth - TclGetInt4AtPtr(pc+1);
-	    while ((tosPtr + length) > eePtr->endPtr) {
-		DECACHE_STACK_INFO();
-		GrowEvaluationStack(eePtr); 
-		CACHE_STACK_INFO();
-	    }
-	    
-	    /*
-	     * Expand the list at stacktop onto the stack; free the list.
-	     */
+	/*
+	 * Make sure there is enough room in the stack to expand this list
+	 * *and* process the rest of the command (at least up to the next
+	 * argument expansion or command end).  The operand is the current
+	 * stack depth, as seen by the compiler.
+	 */ 
+
+	length = objc + codePtr->maxStackDepth - TclGetInt4AtPtr(pc+1);
+	while ((tosPtr + length) > eePtr->endPtr) {
+	    DECACHE_STACK_INFO();
+	    GrowEvaluationStack(eePtr); 
+	    CACHE_STACK_INFO();
+	}
 
-	    for (i = 0; i < objc; i++) {
-		PUSH_OBJECT(objv[i]);
-	    }
-	    TclDecrRefCount(valuePtr);
-	    NEXT_INST_F(5, 0, 0);
+	/*
+	 * Expand the list at stacktop onto the stack; free the list.
+	 */
+
+	for (i = 0; i < objc; i++) {
+	    PUSH_OBJECT(objv[i]);
 	}
+	TclDecrRefCount(valuePtr);
+	NEXT_INST_F(5, 0, 0);
+    }
 
     {
 	/*
 	 * INVOCATION BLOCK
 	 */
-	
+
 	int objc, pcAdjustment;
-	
+
 	case INST_INVOKE_EXPANDED:
             {
 		Tcl_Obj *objPtr;
@@ -2698,8 +2690,7 @@ TclExecuteByteCode(interp, codePtr)
 	    NEXT_INST_F(1, 2, -1); /* already has the correct refCount */
 	}
 
-    case INST_LIST_INDEX_IMM:
-    {
+    case INST_LIST_INDEX_IMM: {
 	/*** lindex with objc==3 and index in bytecode stream ***/
 
 	int listc, idx, opnd;
@@ -4742,6 +4733,11 @@ TclExecuteByteCode(interp, codePtr)
 	TRACE(("=> %u\n", result));
 	NEXT_INST_F(1, 0, 1);
 
+    case INST_PUSH_RETURN_OPTIONS:
+	objResultPtr = Tcl_GetReturnOptions(interp, result);
+	TRACE_WITH_OBJ(("=> "), objResultPtr);
+	NEXT_INST_F(1, 0, 1);
+
     default:
 	Tcl_Panic("TclExecuteByteCode: unrecognized opCode %u", *pc);
     } /* end of switch on opCode */