Use more size_t type internally, when compiling against Tcl 9.0 headers. No change when using Tcl 8.x.

Add C++ travis build for TCL_UTF_MAX=4 (compat with Tcl 8.7) and TCL_UTF_MAX=6 (compat with Tcl 9.0) making sure that C++'s strict typing stays correct.

35 files changed, 357 insertions, 317 deletions

diff --git a/generic/nanosvg.h b/generic/nanosvg.h
index 7bb13d2..7bb13d2 100755..100644
--- a/generic/nanosvg.h
+++ b/generic/nanosvg.h
diff --git a/generic/tk.h b/generic/tk.h
index 3c75b98..1fd72fa 100644
--- a/generic/tk.h
+++ b/generic/tk.h
@@ -238,11 +238,19 @@ typedef struct Tk_OptionSpec {
  * option config code to handle a custom option.
  */
 
+#if TCL_MAJOR_VERSION > 8
+typedef int (Tk_CustomOptionSetProc) (ClientData clientData,
+	Tcl_Interp *interp, Tk_Window tkwin, Tcl_Obj **value, char *widgRec,
+	size_t offset, char *saveInternalPtr, int flags);
+typedef Tcl_Obj *(Tk_CustomOptionGetProc) (ClientData clientData,
+	Tk_Window tkwin, char *widgRec, size_t offset);
+#else
 typedef int (Tk_CustomOptionSetProc) (ClientData clientData,
 	Tcl_Interp *interp, Tk_Window tkwin, Tcl_Obj **value, char *widgRec,
 	int offset, char *saveInternalPtr, int flags);
 typedef Tcl_Obj *(Tk_CustomOptionGetProc) (ClientData clientData,
 	Tk_Window tkwin, char *widgRec, int offset);
+#endif
 typedef void (Tk_CustomOptionRestoreProc) (ClientData clientData,
 	Tk_Window tkwin, char *internalPtr, char *saveInternalPtr);
 typedef void (Tk_CustomOptionFreeProc) (ClientData clientData, Tk_Window tkwin,
@@ -346,10 +354,17 @@ typedef struct Tk_SavedOptions {
 
 #ifndef __NO_OLD_CONFIG
 
+#if TCL_MAJOR_VERSION > 8
+typedef int (Tk_OptionParseProc) (ClientData clientData, Tcl_Interp *interp,
+	Tk_Window tkwin, const char *value, char *widgRec, size_t offset);
+typedef const char *(Tk_OptionPrintProc) (ClientData clientData,
+	Tk_Window tkwin, char *widgRec, size_t offset, Tcl_FreeProc **freeProcPtr);
+#else
 typedef int (Tk_OptionParseProc) (ClientData clientData, Tcl_Interp *interp,
 	Tk_Window tkwin, const char *value, char *widgRec, int offset);
 typedef const char *(Tk_OptionPrintProc) (ClientData clientData,
 	Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr);
+#endif
 
 typedef struct Tk_CustomOption {
     Tk_OptionParseProc *parseProc;
@@ -1067,8 +1082,13 @@ typedef int	(Tk_ItemIndexProc)(Tcl_Interp *interp, Tk_Canvas canvas,
 #endif /* USE_OLD_CANVAS */
 typedef void	(Tk_ItemCursorProc)(Tk_Canvas canvas, Tk_Item *itemPtr,
 		    int index);
+#if TCL_MAJOR_VERSION > 8
+typedef size_t	(Tk_ItemSelectionProc)(Tk_Canvas canvas, Tk_Item *itemPtr,
+		    size_t offset, char *buffer, size_t maxBytes);
+#else
 typedef int	(Tk_ItemSelectionProc)(Tk_Canvas canvas, Tk_Item *itemPtr,
 		    int offset, char *buffer, int maxBytes);
+#endif
 #ifdef USE_OLD_CANVAS
 typedef void	(Tk_ItemInsertProc)(Tk_Canvas canvas, Tk_Item *itemPtr,
 		    int beforeThis, char *string);
@@ -1579,8 +1599,13 @@ typedef int (Tk_GetSelProc) (ClientData clientData, Tcl_Interp *interp,
 typedef void (Tk_LostSelProc) (ClientData clientData);
 typedef Tk_RestrictAction (Tk_RestrictProc) (ClientData clientData,
 	XEvent *eventPtr);
+#if TCL_MAJOR_VERSION > 8
+typedef size_t (Tk_SelectionProc) (ClientData clientData, size_t offset,
+	char *buffer, size_t maxBytes);
+#else
 typedef int (Tk_SelectionProc) (ClientData clientData, int offset,
 	char *buffer, int maxBytes);
+#endif
 
 /*
  *----------------------------------------------------------------------
diff --git a/generic/tkCanvArc.c b/generic/tkCanvArc.c
index 6952f4d..1f78c7c 100644
--- a/generic/tkCanvArc.c
+++ b/generic/tkCanvArc.c
@@ -88,9 +88,9 @@ typedef struct ArcItem {
 
 static int	StyleParseProc(ClientData clientData, Tcl_Interp *interp,
 		    Tk_Window tkwin, const char *value,
-		    char *widgRec, int offset);
+		    char *widgRec, TkSizeT offset);
 static const char * StylePrintProc(ClientData clientData, Tk_Window tkwin,
-		    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr);
+		    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 
 static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
@@ -99,7 +99,7 @@ static const Tk_CustomOption styleOption = {
     StyleParseProc, StylePrintProc, NULL
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 static const Tk_CustomOption dashOption = {
     TkCanvasDashParseProc, TkCanvasDashPrintProc, NULL
@@ -2202,7 +2202,7 @@ StyleParseProc(
     Tk_Window tkwin,		/* Window containing canvas widget. */
     const char *value,		/* Value of option. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item. */
+	TkSizeT offset)			/* Offset into item. */
 {
     int c;
     size_t length;
@@ -2265,7 +2265,7 @@ StylePrintProc(
     ClientData dummy,	/* Ignored. */
     Tk_Window tkwin,		/* Ignored. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Offset into item. */
+	TkSizeT offset,			/* Offset into item. */
     Tcl_FreeProc **freeProcPtr)	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
diff --git a/generic/tkCanvBmap.c b/generic/tkCanvBmap.c
index 3053469..b2dc012 100644
--- a/generic/tkCanvBmap.c
+++ b/generic/tkCanvBmap.c
@@ -45,7 +45,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 
 static const Tk_ConfigSpec configSpecs[] = {
diff --git a/generic/tkCanvImg.c b/generic/tkCanvImg.c
index 34b52ea..53e9c25 100644
--- a/generic/tkCanvImg.c
+++ b/generic/tkCanvImg.c
@@ -47,7 +47,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 
 static const Tk_ConfigSpec configSpecs[] = {
diff --git a/generic/tkCanvLine.c b/generic/tkCanvLine.c
index 0737d76..beb8942 100644
--- a/generic/tkCanvLine.c
+++ b/generic/tkCanvLine.c
@@ -108,15 +108,15 @@ static int		LineToPostscript(Tcl_Interp *interp,
 			    Tk_Canvas canvas, Tk_Item *itemPtr, int prepass);
 static int		ArrowParseProc(ClientData clientData,
 			    Tcl_Interp *interp, Tk_Window tkwin,
-			    const char *value, char *recordPtr, int offset);
+			    const char *value, char *recordPtr, TkSizeT offset);
 static const char * ArrowPrintProc(ClientData clientData,
-			    Tk_Window tkwin, char *recordPtr, int offset,
+			    Tk_Window tkwin, char *recordPtr, TkSizeT offset,
 			    Tcl_FreeProc **freeProcPtr);
 static int		ParseArrowShape(ClientData clientData,
 			    Tcl_Interp *interp, Tk_Window tkwin,
-			    const char *value, char *recordPtr, int offset);
+			    const char *value, char *recordPtr, TkSizeT offset);
 static const char * PrintArrowShape(ClientData clientData,
-			    Tk_Window tkwin, char *recordPtr, int offset,
+			    Tk_Window tkwin, char *recordPtr, TkSizeT offset,
 			    Tcl_FreeProc **freeProcPtr);
 static void		RotateLine(Tk_Canvas canvas, Tk_Item *itemPtr,
 			    double originX, double originY, double angleRad);
@@ -145,7 +145,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 static const Tk_CustomOption dashOption = {
     TkCanvasDashParseProc, TkCanvasDashPrintProc, NULL
@@ -1937,7 +1937,7 @@ ParseArrowShape(
     const char *value,		/* Textual specification of arrow shape. */
     char *recordPtr,		/* Pointer to item record in which to store
 				 * arrow information. */
-    int offset)			/* Offset of shape information in widget
+    TkSizeT offset)			/* Offset of shape information in widget
 				 * record. */
 {
     LineItem *linePtr = (LineItem *) recordPtr;
@@ -2005,7 +2005,7 @@ PrintArrowShape(
     Tk_Window tkwin,		/* Window associated with linePtr's widget. */
     char *recordPtr,		/* Pointer to item record containing current
 				 * shape information. */
-    int offset,			/* Offset of arrow information in record. */
+    TkSizeT offset,			/* Offset of arrow information in record. */
     Tcl_FreeProc **freeProcPtr)	/* Store address of function to call to free
 				 * string here. */
 {
@@ -2046,7 +2046,7 @@ ArrowParseProc(
     Tk_Window tkwin,		/* Window containing canvas widget. */
     const char *value,		/* Value of option. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item. */
+	TkSizeT offset)			/* Offset into item. */
 {
     int c;
     size_t length;
@@ -2113,7 +2113,7 @@ ArrowPrintProc(
     ClientData dummy,	/* Ignored. */
     Tk_Window tkwin,		/* Window containing canvas widget. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Offset into item. */
+	TkSizeT offset,			/* Offset into item. */
     Tcl_FreeProc **freeProcPtr)	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
diff --git a/generic/tkCanvPoly.c b/generic/tkCanvPoly.c
index c0329d6..71e67f8 100644
--- a/generic/tkCanvPoly.c
+++ b/generic/tkCanvPoly.c
@@ -62,7 +62,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 static const Tk_CustomOption dashOption = {
     TkCanvasDashParseProc, TkCanvasDashPrintProc, NULL
diff --git a/generic/tkCanvText.c b/generic/tkCanvText.c
index ab7b882..3c8f364 100644
--- a/generic/tkCanvText.c
+++ b/generic/tkCanvText.c
@@ -32,7 +32,7 @@ typedef struct TextItem {
      */
 
     double x, y;		/* Positioning point for text. */
-    int insertPos;		/* Character index of character just before
+    TkSizeT insertPos;		/* Character index of character just before
 				 * which the insertion cursor is displayed. */
 
     /*
@@ -62,8 +62,8 @@ typedef struct TextItem {
      * configuration settings above.
      */
 
-    int numChars;		/* Length of text in characters. */
-    int numBytes;		/* Length of text in bytes. */
+    TkSizeT numChars;		/* Length of text in characters. */
+    TkSizeT numBytes;		/* Length of text in bytes. */
     Tk_TextLayout textLayout;	/* Cached text layout information. */
     int actualWidth;		/* Width of text as computed. Used to make
 				 * selections of wrapped text display
@@ -87,7 +87,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 static const Tk_CustomOption offsetOption = {
     TkOffsetParseProc, TkOffsetPrintProc, INT2PTR(TK_OFFSET_RELATIVE)
@@ -146,9 +146,9 @@ static void		DeleteText(Tk_Canvas canvas,
 static void		DisplayCanvText(Tk_Canvas canvas,
 			    Tk_Item *itemPtr, Display *display, Drawable dst,
 			    int x, int y, int width, int height);
-static int		GetSelText(Tk_Canvas canvas,
-			    Tk_Item *itemPtr, int offset, char *buffer,
-			    int maxBytes);
+static TkSizeT	GetSelText(Tk_Canvas canvas,
+			    Tk_Item *itemPtr, TkSizeT offset, char *buffer,
+			    TkSizeT maxBytes);
 static int		GetTextIndex(Tcl_Interp *interp,
 			    Tk_Canvas canvas, Tk_Item *itemPtr,
 			    Tcl_Obj *obj, int *indexPtr);
@@ -510,19 +510,19 @@ ConfigureText(
     textPtr->numChars = Tcl_NumUtfChars(textPtr->text, textPtr->numBytes);
     if (textInfoPtr->selItemPtr == itemPtr) {
 
-	if (textInfoPtr->selectFirst >= textPtr->numChars) {
+	if (textInfoPtr->selectFirst >= (int)textPtr->numChars) {
 	    textInfoPtr->selItemPtr = NULL;
 	} else {
-	    if (textInfoPtr->selectLast >= textPtr->numChars) {
+	    if (textInfoPtr->selectLast >= (int)textPtr->numChars) {
 		textInfoPtr->selectLast = textPtr->numChars - 1;
 	    }
 	    if ((textInfoPtr->anchorItemPtr == itemPtr)
-		    && (textInfoPtr->selectAnchor >= textPtr->numChars)) {
+		    && (textInfoPtr->selectAnchor >= (int)textPtr->numChars)) {
 		textInfoPtr->selectAnchor = textPtr->numChars - 1;
 	    }
 	}
     }
-    if (textPtr->insertPos >= textPtr->numChars) {
+    if (textPtr->insertPos + 1 >= textPtr->numChars + 1) {
 	textPtr->insertPos = textPtr->numChars;
     }
 
@@ -846,7 +846,7 @@ DisplayCanvText(
     if (textInfoPtr->selItemPtr == itemPtr) {
 	selFirstChar = textInfoPtr->selectFirst;
 	selLastChar = textInfoPtr->selectLast;
-	if (selLastChar > textPtr->numChars) {
+	if (selLastChar > (int)textPtr->numChars) {
 	    selLastChar = textPtr->numChars - 1;
 	}
 	if ((selFirstChar >= 0) && (selFirstChar <= selLastChar)) {
@@ -969,7 +969,7 @@ DisplayCanvText(
 	TkDrawAngledTextLayout(display, drawable, textPtr->selTextGC,
 		textPtr->textLayout, drawableX, drawableY, textPtr->angle,
 		selFirstChar, selLastChar + 1);
-	if (selLastChar + 1 < textPtr->numChars) {
+	if (selLastChar + 1 < (int)textPtr->numChars) {
 	    TkDrawAngledTextLayout(display, drawable, textPtr->gc,
 		    textPtr->textLayout, drawableX, drawableY, textPtr->angle,
 		    selLastChar + 1, textPtr->numChars);
@@ -1027,7 +1027,7 @@ TextInsert(
     if (index < 0) {
 	index = 0;
     }
-    if (index > textPtr->numChars) {
+    if (index > (int)textPtr->numChars) {
 	index = textPtr->numChars;
     }
     byteIndex = Tcl_UtfAtIndex(text, index) - text;
@@ -1064,7 +1064,7 @@ TextInsert(
 	    textInfoPtr->selectAnchor += charsAdded;
 	}
     }
-    if (textPtr->insertPos >= index) {
+    if (textPtr->insertPos + 1 >= (TkSizeT)index + 1) {
 	textPtr->insertPos += charsAdded;
     }
     ComputeTextBbox(canvas, textPtr);
@@ -1105,7 +1105,7 @@ TextDeleteChars(
     if (first < 0) {
 	first = 0;
     }
-    if (last >= textPtr->numChars) {
+    if (last >= (int)textPtr->numChars) {
 	last = textPtr->numChars - 1;
     }
     if (first > last) {
@@ -1155,9 +1155,9 @@ TextDeleteChars(
 	    }
 	}
     }
-    if (textPtr->insertPos > first) {
+    if ((int)textPtr->insertPos > first) {
 	textPtr->insertPos -= charsRemoved;
-	if (textPtr->insertPos < first) {
+	if ((int)textPtr->insertPos < first) {
 	    textPtr->insertPos = first;
 	}
     }
@@ -1393,7 +1393,7 @@ GetTextIndex(
     if (TCL_OK == TkGetIntForIndex(obj, textPtr->numChars - 1, 1, &idx)) {
 	if (idx == TCL_INDEX_NONE) {
 	    idx = 0;
-	} else if (idx > (TkSizeT)textPtr->numChars) {
+	} else if (idx > textPtr->numChars) {
 	    idx = textPtr->numChars;
 	}
 	*indexPtr = (int)idx;
@@ -1489,7 +1489,7 @@ SetTextCursor(
 
     if (index < 0) {
 	textPtr->insertPos = 0;
-    } else if (index > textPtr->numChars) {
+    } else if (index > (int)textPtr->numChars) {
 	textPtr->insertPos = textPtr->numChars;
     } else {
 	textPtr->insertPos = index;
@@ -1516,25 +1516,25 @@ SetTextCursor(
  *--------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 GetSelText(
     Tk_Canvas canvas,		/* Canvas containing selection. */
     Tk_Item *itemPtr,		/* Text item containing selection. */
-    int offset,			/* Byte offset within selection of first
+	TkSizeT offset,			/* Byte offset within selection of first
 				 * character to be returned. */
     char *buffer,		/* Location in which to place selection. */
-    int maxBytes)		/* Maximum number of bytes to place at buffer,
+	TkSizeT maxBytes)		/* Maximum number of bytes to place at buffer,
 				 * not including terminating NULL
 				 * character. */
 {
     TextItem *textPtr = (TextItem *) itemPtr;
-    int byteCount;
+    TkSizeT byteCount;
     char *text;
     const char *selStart, *selEnd;
     Tk_CanvasTextInfo *textInfoPtr = textPtr->textInfoPtr;
     (void)canvas;
 
-    if ((textInfoPtr->selectFirst < 0) ||
+    if ((textInfoPtr->selectFirst == -1) ||
 	    (textInfoPtr->selectFirst > textInfoPtr->selectLast)) {
 	return 0;
     }
@@ -1542,13 +1542,13 @@ GetSelText(
     selStart = Tcl_UtfAtIndex(text, textInfoPtr->selectFirst);
     selEnd = Tcl_UtfAtIndex(selStart,
 	    textInfoPtr->selectLast + 1 - textInfoPtr->selectFirst);
+    if (selEnd  <= selStart + offset) {
+	return 0;
+    }
     byteCount = selEnd - selStart - offset;
     if (byteCount > maxBytes) {
 	byteCount = maxBytes;
     }
-    if (byteCount <= 0) {
-	return 0;
-    }
     memcpy(buffer, selStart + offset, byteCount);
     buffer[byteCount] = '\0';
     return byteCount;
diff --git a/generic/tkCanvUtil.c b/generic/tkCanvUtil.c
index 1d6a394..eee1ad2 100644
--- a/generic/tkCanvUtil.c
+++ b/generic/tkCanvUtil.c
@@ -402,13 +402,13 @@ Tk_CanvasGetTextInfo(
  */
 
 int
-Tk_CanvasTagsParseProc(
+TkCanvasTagsParseProc(
     ClientData dummy,	/* Not used.*/
     Tcl_Interp *interp,		/* Used for reporting errors. */
     Tk_Window tkwin,		/* Window containing canvas widget. */
     const char *value,		/* Value of option (list of tag names). */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item (ignored). */
+    TkSizeT offset)			/* Offset into item (ignored). */
 {
     Tk_Item *itemPtr = (Tk_Item *) widgRec;
     int argc, i;
@@ -472,11 +472,11 @@ Tk_CanvasTagsParseProc(
  */
 
 const char *
-Tk_CanvasTagsPrintProc(
+TkCanvasTagsPrintProc(
     ClientData dummy,	/* Ignored. */
     Tk_Window tkwin,		/* Window containing canvas widget. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Ignored. */
+    TkSizeT offset,			/* Ignored. */
     Tcl_FreeProc **freeProcPtr)	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
@@ -523,7 +523,7 @@ TkCanvasDashParseProc(
     Tk_Window tkwin,		/* Window containing canvas widget. */
     const char *value,		/* Value of option. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item. */
+    TkSizeT offset)			/* Offset into item. */
 {
     (void)dummy;
     (void)tkwin;
@@ -558,7 +558,7 @@ TkCanvasDashPrintProc(
     ClientData dummy,	/* Ignored. */
     Tk_Window tkwin,		/* Window containing canvas widget. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Offset in record for item. */
+	TkSizeT offset,			/* Offset in record for item. */
     Tcl_FreeProc **freeProcPtr)	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
@@ -747,7 +747,7 @@ TkSmoothParseProc(
     Tk_Window tkwin,		/* Window containing canvas widget. */
     const char *value,		/* Value of option. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item. */
+	TkSizeT offset)			/* Offset into item. */
 {
     const Tk_SmoothMethod **smoothPtr =
 	    (const Tk_SmoothMethod **) (widgRec + offset);
@@ -839,7 +839,7 @@ TkSmoothPrintProc(
     ClientData dummy,	/* Ignored. */
     Tk_Window tkwin,		/* Window containing canvas widget. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Offset into item. */
+    TkSizeT offset,			/* Offset into item. */
     Tcl_FreeProc **freeProcPtr)	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
diff --git a/generic/tkCanvWind.c b/generic/tkCanvWind.c
index 22729d6..8028c14 100644
--- a/generic/tkCanvWind.c
+++ b/generic/tkCanvWind.c
@@ -41,7 +41,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 
 static const Tk_ConfigSpec configSpecs[] = {
diff --git a/generic/tkCanvas.c b/generic/tkCanvas.c
index d3868d5..54087e6 100644
--- a/generic/tkCanvas.c
+++ b/generic/tkCanvas.c
@@ -223,8 +223,8 @@ static void		CanvasCmdDeletedProc(ClientData clientData);
 static void		CanvasDoEvent(TkCanvas *canvasPtr, XEvent *eventPtr);
 static void		CanvasEventProc(ClientData clientData,
 			    XEvent *eventPtr);
-static int		CanvasFetchSelection(ClientData clientData, int offset,
-			    char *buffer, int maxBytes);
+static TkSizeT	CanvasFetchSelection(ClientData clientData, TkSizeT offset,
+			    char *buffer, TkSizeT maxBytes);
 static Tk_Item *	CanvasFindClosest(TkCanvas *canvasPtr,
 			    double coords[2]);
 static void		CanvasFocusProc(TkCanvas *canvasPtr, int gotFocus);
@@ -5689,13 +5689,13 @@ CanvasSelectTo(
  *--------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 CanvasFetchSelection(
     ClientData clientData,	/* Information about canvas widget. */
-    int offset,			/* Offset within selection of first character
+	TkSizeT offset,			/* Offset within selection of first character
 				 * to be returned. */
     char *buffer,		/* Location in which to place selection. */
-    int maxBytes)		/* Maximum number of bytes to place at buffer,
+	TkSizeT maxBytes)		/* Maximum number of bytes to place at buffer,
 				 * not including terminating NULL
 				 * character. */
 {
diff --git a/generic/tkClipboard.c b/generic/tkClipboard.c
index f09958e..308be14 100644
--- a/generic/tkClipboard.c
+++ b/generic/tkClipboard.c
@@ -19,12 +19,12 @@
  * Prototypes for functions used only in this file:
  */
 
-static int		ClipboardAppHandler(ClientData clientData,
-			    int offset, char *buffer, int maxBytes);
-static int		ClipboardHandler(ClientData clientData,
-			    int offset, char *buffer, int maxBytes);
-static int		ClipboardWindowHandler(ClientData clientData,
-			    int offset, char *buffer, int maxBytes);
+static TkSizeT	ClipboardAppHandler(ClientData clientData,
+			    TkSizeT offset, char *buffer, TkSizeT maxBytes);
+static TkSizeT	ClipboardHandler(ClientData clientData,
+			    TkSizeT offset, char *buffer, TkSizeT maxBytes);
+static TkSizeT	ClipboardWindowHandler(ClientData clientData,
+			    TkSizeT offset, char *buffer, TkSizeT maxBytes);
 static void		ClipboardLostSel(ClientData clientData);
 static int		ClipboardGetProc(ClientData clientData,
 			    Tcl_Interp *interp, const char *portion);
@@ -48,20 +48,20 @@ static int		ClipboardGetProc(ClientData clientData,
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 ClipboardHandler(
     ClientData clientData,	/* Information about data to fetch. */
-    int offset,			/* Return selection bytes starting at this
+    TkSizeT offset,			/* Return selection bytes starting at this
 				 * offset. */
     char *buffer,		/* Place to store converted selection. */
-    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+    TkSizeT maxBytes)		/* Maximum # of bytes to store at buffer. */
 {
     TkClipboardTarget *targetPtr = (TkClipboardTarget *)clientData;
     TkClipboardBuffer *cbPtr;
     char *srcPtr, *destPtr;
-    size_t count = 0;
-    size_t scanned = 0;
-    size_t length, freeCount;
+    TkSizeT count = 0;
+    TkSizeT scanned = 0;
+    TkSizeT length, freeCount;
 
     /*
      * Skip to buffer containing offset byte
@@ -71,7 +71,7 @@ ClipboardHandler(
 	if (cbPtr == NULL) {
 	    return 0;
 	}
-	if (scanned + cbPtr->length > (size_t)offset) {
+	if (scanned + cbPtr->length > offset) {
 	    break;
 	}
 	scanned += cbPtr->length;
@@ -102,7 +102,7 @@ ClipboardHandler(
 	srcPtr = cbPtr->buffer;
 	length = cbPtr->length;
     }
-    return (int)count;
+    return count;
 }
 
 /*
@@ -126,30 +126,30 @@ ClipboardHandler(
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 ClipboardAppHandler(
     ClientData clientData,	/* Pointer to TkDisplay structure. */
-    int offset,			/* Return selection bytes starting at this
+	TkSizeT offset,			/* Return selection bytes starting at this
 				 * offset. */
     char *buffer,		/* Place to store converted selection. */
-    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+	TkSizeT maxBytes)		/* Maximum # of bytes to store at buffer. */
 {
     TkDisplay *dispPtr = (TkDisplay *)clientData;
-    size_t length;
+    TkSizeT length;
     const char *p;
 
     p = dispPtr->clipboardAppPtr->winPtr->nameUid;
     length = strlen(p);
-    length -= offset;
-    if (length <= 0) {
+    if (length <= offset) {
 	return 0;
     }
-    if (length > (size_t) maxBytes) {
+    length -= offset;
+    if (length > maxBytes) {
 	length = maxBytes;
     }
     memcpy(buffer, p, length);
     buffer[length] = 0;
-    return (int)length;
+    return length;
 }
 
 /*
@@ -171,13 +171,13 @@ ClipboardAppHandler(
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 ClipboardWindowHandler(
     ClientData dummy,	/* Not used. */
-    int offset,			/* Return selection bytes starting at this
+	TkSizeT offset,			/* Return selection bytes starting at this
 				 * offset. */
     char *buffer,		/* Place to store converted selection. */
-    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+	TkSizeT maxBytes)		/* Maximum # of bytes to store at buffer. */
 {
     (void)dummy;
     (void)offset;
diff --git a/generic/tkEntry.c b/generic/tkEntry.c
index bffe8b8..e331dcb 100644
--- a/generic/tkEntry.c
+++ b/generic/tkEntry.c
@@ -412,8 +412,8 @@ static void		EntryComputeGeometry(Entry *entryPtr);
 static void		EntryEventProc(ClientData clientData,
 			    XEvent *eventPtr);
 static void		EntryFocusProc(Entry *entryPtr, int gotFocus);
-static int		EntryFetchSelection(ClientData clientData, int offset,
-			    char *buffer, int maxBytes);
+static TkSizeT	EntryFetchSelection(ClientData clientData, TkSizeT offset,
+			    char *buffer, TkSizeT maxBytes);
 static void		EntryLostSelection(ClientData clientData);
 static void		EventuallyRedraw(Entry *entryPtr);
 static void		EntryScanTo(Entry *entryPtr, int y);
@@ -637,7 +637,7 @@ EntryWidgetObjCmd(
 		&index) != TCL_OK) {
 	    goto error;
 	}
-	if ((index == entryPtr->numChars) && (index > 0)) {
+	if ((index == (int)entryPtr->numChars) && (index > 0)) {
 	    index--;
 	}
 	Tk_CharBbox(entryPtr->textLayout, index, &x, &y, &width, &height);
@@ -989,7 +989,7 @@ EntryWidgetObjCmd(
 		break;
 	    }
 	}
-	if (index >= entryPtr->numChars) {
+	if (index >= (int)entryPtr->numChars) {
 	    index = entryPtr->numChars - 1;
 	}
 	if (index < 0) {
@@ -1706,8 +1706,8 @@ DisplayEntry(
 	    0, 0, Tk_Width(tkwin), Tk_Height(tkwin), 0, TK_RELIEF_FLAT);
 
     if (showSelection && (entryPtr->state != STATE_DISABLED)
-	    && (entryPtr->selectLast > entryPtr->leftIndex)) {
-	if (entryPtr->selectFirst <= entryPtr->leftIndex) {
+	    && (entryPtr->selectLast > (int)entryPtr->leftIndex)) {
+	if (entryPtr->selectFirst <= (int)entryPtr->leftIndex) {
 	    selStartX = entryPtr->leftX;
 	} else {
 	    Tk_CharBbox(entryPtr->textLayout, entryPtr->selectFirst,
@@ -1749,7 +1749,7 @@ DisplayEntry(
 	cursorX -= (entryPtr->insertWidth == 1) ? 1 : (entryPtr->insertWidth)/2;
 	Tk_SetCaretPos(entryPtr->tkwin, cursorX, baseY - fm.ascent,
 		fm.ascent + fm.descent);
-	if (entryPtr->insertPos >= entryPtr->leftIndex && cursorX < xBound) {
+	if ((entryPtr->insertPos >= (int)entryPtr->leftIndex) && cursorX < xBound) {
 	    if (entryPtr->flags & CURSOR_ON) {
 		Tk_Fill3DRectangle(tkwin, pixmap, entryPtr->insertBorder,
 			cursorX, baseY - fm.ascent, entryPtr->insertWidth,
@@ -1783,7 +1783,7 @@ DisplayEntry(
 	    && (entryPtr->selectFirst < entryPtr->selectLast)) {
 	int selFirst;
 
-	if (entryPtr->selectFirst < entryPtr->leftIndex) {
+	if (entryPtr->selectFirst < (int)entryPtr->leftIndex) {
 	    selFirst = entryPtr->leftIndex;
 	} else {
 	    selFirst = entryPtr->selectFirst;
@@ -1982,7 +1982,7 @@ EntryComputeGeometry(
 	p = (char *)ckalloc(entryPtr->numDisplayBytes + 1);
 	entryPtr->displayString = p;
 
-	for (i = entryPtr->numChars; --i >= 0; ) {
+	for (i = entryPtr->numChars; i-- > 0; ) {
 	    memcpy(p, buf, size);
 	    p += size;
 	}
@@ -2083,7 +2083,7 @@ EntryComputeGeometry(
 	if (rightX < overflow) {
 	    maxOffScreen++;
 	}
-	if (entryPtr->leftIndex > maxOffScreen) {
+	if (entryPtr->leftIndex + 1 > (TkSizeT)maxOffScreen + 1) {
 	    entryPtr->leftIndex = maxOffScreen;
 	}
 	Tk_CharBbox(entryPtr->textLayout, entryPtr->leftIndex, &rightX,
@@ -2200,7 +2200,7 @@ InsertChars(
     if ((entryPtr->selectAnchor > index) || (entryPtr->selectFirst >= index)) {
 	entryPtr->selectAnchor += charsAdded;
     }
-    if (entryPtr->leftIndex > index) {
+    if (entryPtr->leftIndex + 1 > (TkSizeT)index + 1) {
 	entryPtr->leftIndex += charsAdded;
     }
     if (entryPtr->insertPos >= index) {
@@ -2237,7 +2237,7 @@ DeleteChars(
     const char *string;
     char *newStr, *toDelete;
 
-    if ((index + count) > entryPtr->numChars) {
+    if ((index + count) > (int)entryPtr->numChars) {
 	count = entryPtr->numChars - index;
     }
     if (count <= 0) {
@@ -2308,8 +2308,8 @@ DeleteChars(
 	    entryPtr->selectAnchor = index;
 	}
     }
-    if (entryPtr->leftIndex > index) {
-	if (entryPtr->leftIndex >= (index + count)) {
+    if (entryPtr->leftIndex + 1 > (TkSizeT)index + 1) {
+	if (entryPtr->leftIndex + 1 >= (TkSizeT)index + count + 1) {
 	    entryPtr->leftIndex -= count;
 	} else {
 	    entryPtr->leftIndex = index;
@@ -2482,21 +2482,21 @@ EntrySetValue(
     }
 
     if (entryPtr->selectFirst >= 0) {
-	if (entryPtr->selectFirst >= entryPtr->numChars) {
+	if (entryPtr->selectFirst >= (int)entryPtr->numChars) {
 	    entryPtr->selectFirst = -1;
 	    entryPtr->selectLast = -1;
-	} else if (entryPtr->selectLast > entryPtr->numChars) {
+	} else if (entryPtr->selectLast > (int)entryPtr->numChars) {
 	    entryPtr->selectLast = entryPtr->numChars;
 	}
     }
-    if (entryPtr->leftIndex >= entryPtr->numChars) {
-	if (entryPtr->numChars > 0) {
+    if (entryPtr->leftIndex + 1 >= entryPtr->numChars + 1) {
+	if (entryPtr->numChars + 1 > 1) {
 	    entryPtr->leftIndex = entryPtr->numChars - 1;
 	} else {
 	    entryPtr->leftIndex = 0;
 	}
     }
-    if (entryPtr->insertPos > entryPtr->numChars) {
+    if (entryPtr->insertPos > (int)entryPtr->numChars) {
 	entryPtr->insertPos = entryPtr->numChars;
     }
 
@@ -2657,8 +2657,8 @@ GetEntryIndex(
     if (TCL_OK == TkGetIntForIndex(indexObj, entryPtr->numChars - 1, 1, &idx)) {
 	if (idx == TCL_INDEX_NONE) {
 	    idx = 0;
-	} else if (idx > (TkSizeT)entryPtr->numChars) {
-	    idx = (TkSizeT)entryPtr->numChars;
+	} else if (idx > entryPtr->numChars) {
+	    idx = entryPtr->numChars;
 	}
 	*indexPtr = (int)idx;
 	return TCL_OK;
@@ -2680,7 +2680,7 @@ GetEntryIndex(
 	*indexPtr = entryPtr->insertPos;
 	break;
     case 's':
-	if (entryPtr->selectFirst < 0) {
+	if (entryPtr->selectFirst == -1) {
 	    Tcl_ResetResult(interp);
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		    "selection isn't in widget %s",
@@ -2727,7 +2727,7 @@ GetEntryIndex(
 	 * be selected, for example.
 	 */
 
-	if (roundUp && (*indexPtr < entryPtr->numChars)) {
+	if (roundUp && (*indexPtr < (int)entryPtr->numChars)) {
 	    *indexPtr += 1;
 	}
 	break;
@@ -2781,7 +2781,7 @@ EntryScanTo(
 
     newLeftIndex = entryPtr->scanMarkIndex
 	    - (10 * (x - entryPtr->scanMarkX)) / entryPtr->avgWidth;
-    if (newLeftIndex >= entryPtr->numChars) {
+    if (newLeftIndex >= (int)entryPtr->numChars) {
 	newLeftIndex = entryPtr->scanMarkIndex = entryPtr->numChars - 1;
 	entryPtr->scanMarkX = x;
     }
@@ -2790,11 +2790,11 @@ EntryScanTo(
 	entryPtr->scanMarkX = x;
     }
 
-    if (newLeftIndex != entryPtr->leftIndex) {
+    if ((TkSizeT)newLeftIndex != entryPtr->leftIndex) {
 	entryPtr->leftIndex = newLeftIndex;
 	entryPtr->flags |= UPDATE_SCROLLBAR;
 	EntryComputeGeometry(entryPtr);
-	if (newLeftIndex != entryPtr->leftIndex) {
+	if ((TkSizeT)newLeftIndex != entryPtr->leftIndex) {
 	    entryPtr->scanMarkIndex = entryPtr->leftIndex;
 	    entryPtr->scanMarkX = x;
 	}
@@ -2842,8 +2842,8 @@ EntrySelectTo(
      * Pick new starting and ending points for the selection.
      */
 
-    if (entryPtr->selectAnchor > entryPtr->numChars) {
-	entryPtr->selectAnchor = entryPtr->numChars;
+    if (entryPtr->selectAnchor > (int)entryPtr->numChars) {
+	entryPtr->selectAnchor = (int)entryPtr->numChars;
     }
     if (entryPtr->selectAnchor <= index) {
 	newFirst = entryPtr->selectAnchor;
@@ -2885,21 +2885,21 @@ EntrySelectTo(
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 EntryFetchSelection(
     ClientData clientData,	/* Information about entry widget. */
-    int offset,			/* Byte offset within selection of first
+	TkSizeT offset,			/* Byte offset within selection of first
 				 * character to be returned. */
     char *buffer,		/* Location in which to place selection. */
-    int maxBytes)		/* Maximum number of bytes to place at buffer,
+	TkSizeT maxBytes)		/* Maximum number of bytes to place at buffer,
 				 * not including terminating NUL character. */
 {
     Entry *entryPtr = (Entry *)clientData;
-    int byteCount;
+    TkSizeT byteCount;
     const char *string;
     const char *selStart, *selEnd;
 
-    if ((entryPtr->selectFirst < 0) || (!entryPtr->exportSelection)
+    if ((entryPtr->selectFirst == -1) || (!entryPtr->exportSelection)
 	    || Tcl_IsSafe(entryPtr->interp)) {
 	return -1;
     }
@@ -2907,14 +2907,14 @@ EntryFetchSelection(
     selStart = Tcl_UtfAtIndex(string, entryPtr->selectFirst);
     selEnd = Tcl_UtfAtIndex(selStart,
 	    entryPtr->selectLast - entryPtr->selectFirst);
+    if (selEnd <= selStart + offset) {
+	return 0;
+    }
     byteCount = selEnd - selStart - offset;
     if (byteCount > maxBytes) {
 	byteCount = maxBytes;
     }
-    if (byteCount <= 0) {
-	return 0;
-    }
-    memcpy(buffer, selStart + offset, (size_t) byteCount);
+    memcpy(buffer, selStart + offset, byteCount);
     buffer[byteCount] = '\0';
     return byteCount;
 }
@@ -3035,7 +3035,7 @@ EntryVisibleRange(
 	charsInWindow = Tk_PointToChar(entryPtr->textLayout,
 		Tk_Width(entryPtr->tkwin) - entryPtr->inset
 		- entryPtr->xWidth - entryPtr->layoutX - 1, 0);
-	if (charsInWindow < entryPtr->numChars) {
+	if (charsInWindow < (int)entryPtr->numChars) {
 	    charsInWindow++;
 	}
 	charsInWindow -= entryPtr->leftIndex;
@@ -3845,7 +3845,7 @@ SpinboxWidgetObjCmd(
 		&index) != TCL_OK) {
 	    goto error;
 	}
-	if ((index == entryPtr->numChars) && (index > 0)) {
+	if ((index == (int)entryPtr->numChars) && (index > 0)) {
 	    index--;
 	}
 	Tk_CharBbox(entryPtr->textLayout, index, &x, &y, &width, &height);
@@ -4275,7 +4275,7 @@ SpinboxWidgetObjCmd(
 		break;
 	    }
 	}
-	if (index >= entryPtr->numChars) {
+	if (index >= (int)entryPtr->numChars) {
 	    index = entryPtr->numChars - 1;
 	}
 	if (index < 0) {
diff --git a/generic/tkEntry.h b/generic/tkEntry.h
index c81563c..f251185 100644
--- a/generic/tkEntry.h
+++ b/generic/tkEntry.h
@@ -134,7 +134,7 @@ typedef struct {
 
     Tk_TextLayout placeholderLayout;/* Cached placeholder text layout information. */
     char *placeholderString;	/* String value of placeholder. */
-    int placeholderChars;	/* Number of chars in placeholder. */
+    TkSizeT placeholderChars;	/* Number of chars in placeholder. */
     XColor *placeholderColorPtr;/* Color value of placeholder foreground. */
     GC placeholderGC;		/* For drawing placeholder text. */
     int placeholderX;		/* Origin for layout. */
@@ -151,13 +151,13 @@ typedef struct {
 				 * malloced memory with the same character
 				 * length as string but whose characters are
 				 * all equal to showChar. */
-    int numBytes;		/* Length of string in bytes. */
-    int numChars;		/* Length of string in characters. Both string
+    TkSizeT numBytes;		/* Length of string in bytes. */
+    TkSizeT numChars;		/* Length of string in characters. Both string
 				 * and displayString have the same character
 				 * length, but may have different byte lengths
 				 * due to being made from different UTF-8
 				 * characters. */
-    int numDisplayBytes;	/* Length of displayString in bytes. */
+    TkSizeT numDisplayBytes;	/* Length of displayString in bytes. */
     int inset;			/* Number of pixels on the left and right
 				 * sides that are taken up by XPAD,
 				 * borderWidth (if any), and highlightWidth
@@ -166,7 +166,7 @@ typedef struct {
     int layoutX, layoutY;	/* Origin for layout. */
     int leftX;			/* X position at which character at leftIndex
 				 * is drawn (varies depending on justify). */
-    int leftIndex;		/* Character index of left-most character
+    TkSizeT leftIndex;		/* Character index of left-most character
 				 * visible in window. */
     Tcl_TimerToken insertBlinkHandler;
 				/* Timer handler used to blink cursor on and
diff --git a/generic/tkInt.decls b/generic/tkInt.decls
index dd493e9..4ac3bab 100644
--- a/generic/tkInt.decls
+++ b/generic/tkInt.decls
@@ -567,51 +567,51 @@ declare 168 {
 # Next group of functions exposed due to [Bug 2768945].
 declare 169 {
     int TkStateParseProc(ClientData clientData, Tcl_Interp *interp,
-	    Tk_Window tkwin, const char *value, char *widgRec, int offset)
+	    Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset)
 }
 declare 170 {
     const char *TkStatePrintProc(ClientData clientData, Tk_Window tkwin,
-	    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr)
+	    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr)
 }
 declare 171 {
     int TkCanvasDashParseProc(ClientData clientData, Tcl_Interp *interp,
-	    Tk_Window tkwin, const char *value, char *widgRec, int offset)
+	    Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset)
 }
 declare 172 {
     const char *TkCanvasDashPrintProc(ClientData clientData, Tk_Window tkwin,
-	    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr)
+	    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr)
 }
 declare 173 {
     int TkOffsetParseProc(ClientData clientData, Tcl_Interp *interp,
-	    Tk_Window tkwin, const char *value, char *widgRec, int offset)
+	    Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset)
 }
 declare 174 {
     const char *TkOffsetPrintProc(ClientData clientData, Tk_Window tkwin,
-	    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr)
+	    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr)
 }
 declare 175 {
     int TkPixelParseProc(ClientData clientData, Tcl_Interp *interp,
-	    Tk_Window tkwin, const char *value, char *widgRec, int offset)
+	    Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset)
 }
 declare 176 {
     const char *TkPixelPrintProc(ClientData clientData, Tk_Window tkwin,
-	    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr)
+	    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr)
 }
 declare 177 {
     int TkOrientParseProc(ClientData clientData, Tcl_Interp *interp,
-	    Tk_Window tkwin, const char *value, char *widgRec, int offset)
+	    Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset)
 }
 declare 178 {
     const char *TkOrientPrintProc(ClientData clientData, Tk_Window tkwin,
-	    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr)
+	    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr)
 }
 declare 179 {
     int TkSmoothParseProc(ClientData clientData, Tcl_Interp *interp,
-	    Tk_Window tkwin, const char *value, char *widgRec, int offset)
+	    Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset)
 }
 declare 180 {
     const char *TkSmoothPrintProc(ClientData clientData, Tk_Window tkwin,
-	    char *widgRec, int offset, Tcl_FreeProc **freeProcPtr)
+	    char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr)
 }
 
 # Angled text API, exposed for Emiliano Gavilán's RBC work.
diff --git a/generic/tkInt.h b/generic/tkInt.h
index 6ebf8eb..ab06435 100644
--- a/generic/tkInt.h
+++ b/generic/tkInt.h
@@ -1283,6 +1283,15 @@ MODULE_SCOPE int	TkGetDoublePixels(Tcl_Interp *interp, Tk_Window tkwin,
 MODULE_SCOPE int	TkPostscriptImage(Tcl_Interp *interp, Tk_Window tkwin,
 			    Tk_PostscriptInfo psInfo, XImage *ximage,
 			    int x, int y, int width, int height);
+#if TCL_MAJOR_VERSION > 8
+MODULE_SCOPE int TkCanvasTagsParseProc(ClientData clientData, Tcl_Interp *interp,
+    Tk_Window tkwin, const char *value, char *widgRec, size_t offset);
+MODULE_SCOPE const char *TkCanvasTagsPrintProc(ClientData clientData, Tk_Window tkwin,
+    char *widgRec, size_t offset, Tcl_FreeProc **freeProcPtr);
+#else
+#define TkCanvasTagsParseProc Tk_CanvasTagsParseProc
+#define TkCanvasTagsPrintProc Tk_CanvasTagsPrintProc
+#endif
 MODULE_SCOPE void       TkMapTopFrame(Tk_Window tkwin);
 MODULE_SCOPE XEvent *	TkpGetBindingXEvent(Tcl_Interp *interp);
 MODULE_SCOPE void	TkCreateExitHandler(Tcl_ExitProc *proc,
@@ -1390,8 +1399,8 @@ MODULE_SCOPE void	TkUnixSetXftClipRegion(Region clipRegion);
 #endif
 
 #if TCL_UTF_MAX > 4
-#   define TkUtfToUniChar (size_t)Tcl_UtfToUniChar
-#   define TkUniCharToUtf (size_t)Tcl_UniCharToUtf
+#   define TkUtfToUniChar(src, ch) (size_t)(((int (*)(const char *, int *))Tcl_UtfToUniChar)(src, ch))
+#   define TkUniCharToUtf(ch, src) (size_t)(((int (*)(int, char *))Tcl_UniCharToUtf)(ch, src))
 #   define TkUtfPrev Tcl_UtfPrev
 #else
     MODULE_SCOPE size_t TkUtfToUniChar(const char *, int *);
diff --git a/generic/tkIntDecls.h b/generic/tkIntDecls.h
index 0b3a3cc..f241b75 100644
--- a/generic/tkIntDecls.h
+++ b/generic/tkIntDecls.h
@@ -488,51 +488,57 @@ EXTERN void		TkTextInsertDisplayProc(struct TkText *textPtr,
 /* 169 */
 EXTERN int		TkStateParseProc(ClientData clientData,
 				Tcl_Interp *interp, Tk_Window tkwin,
-				const char *value, char *widgRec, int offset);
+				const char *value, char *widgRec,
+				TkSizeT offset);
 /* 170 */
 EXTERN const char *	TkStatePrintProc(ClientData clientData,
-				Tk_Window tkwin, char *widgRec, int offset,
-				Tcl_FreeProc **freeProcPtr);
+				Tk_Window tkwin, char *widgRec,
+				TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 /* 171 */
 EXTERN int		TkCanvasDashParseProc(ClientData clientData,
 				Tcl_Interp *interp, Tk_Window tkwin,
-				const char *value, char *widgRec, int offset);
+				const char *value, char *widgRec,
+				TkSizeT offset);
 /* 172 */
 EXTERN const char *	TkCanvasDashPrintProc(ClientData clientData,
-				Tk_Window tkwin, char *widgRec, int offset,
-				Tcl_FreeProc **freeProcPtr);
+				Tk_Window tkwin, char *widgRec,
+				TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 /* 173 */
 EXTERN int		TkOffsetParseProc(ClientData clientData,
 				Tcl_Interp *interp, Tk_Window tkwin,
-				const char *value, char *widgRec, int offset);
+				const char *value, char *widgRec,
+				TkSizeT offset);
 /* 174 */
 EXTERN const char *	TkOffsetPrintProc(ClientData clientData,
-				Tk_Window tkwin, char *widgRec, int offset,
-				Tcl_FreeProc **freeProcPtr);
+				Tk_Window tkwin, char *widgRec,
+				TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 /* 175 */
 EXTERN int		TkPixelParseProc(ClientData clientData,
 				Tcl_Interp *interp, Tk_Window tkwin,
-				const char *value, char *widgRec, int offset);
+				const char *value, char *widgRec,
+				TkSizeT offset);
 /* 176 */
 EXTERN const char *	TkPixelPrintProc(ClientData clientData,
-				Tk_Window tkwin, char *widgRec, int offset,
-				Tcl_FreeProc **freeProcPtr);
+				Tk_Window tkwin, char *widgRec,
+				TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 /* 177 */
 EXTERN int		TkOrientParseProc(ClientData clientData,
 				Tcl_Interp *interp, Tk_Window tkwin,
-				const char *value, char *widgRec, int offset);
+				const char *value, char *widgRec,
+				TkSizeT offset);
 /* 178 */
 EXTERN const char *	TkOrientPrintProc(ClientData clientData,
-				Tk_Window tkwin, char *widgRec, int offset,
-				Tcl_FreeProc **freeProcPtr);
+				Tk_Window tkwin, char *widgRec,
+				TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 /* 179 */
 EXTERN int		TkSmoothParseProc(ClientData clientData,
 				Tcl_Interp *interp, Tk_Window tkwin,
-				const char *value, char *widgRec, int offset);
+				const char *value, char *widgRec,
+				TkSizeT offset);
 /* 180 */
 EXTERN const char *	TkSmoothPrintProc(ClientData clientData,
-				Tk_Window tkwin, char *widgRec, int offset,
-				Tcl_FreeProc **freeProcPtr);
+				Tk_Window tkwin, char *widgRec,
+				TkSizeT offset, Tcl_FreeProc **freeProcPtr);
 /* 181 */
 EXTERN void		TkDrawAngledTextLayout(Display *display,
 				Drawable drawable, GC gc,
@@ -757,18 +763,18 @@ typedef struct TkIntStubs {
     void (*tkTextChanged) (struct TkSharedText *sharedTextPtr, struct TkText *textPtr, const struct TkTextIndex *index1Ptr, const struct TkTextIndex *index2Ptr); /* 166 */
     int (*tkBTreeNumLines) (TkTextBTree tree, const struct TkText *textPtr); /* 167 */
     void (*tkTextInsertDisplayProc) (struct TkText *textPtr, struct TkTextDispChunk *chunkPtr, int x, int y, int height, int baseline, Display *display, Drawable dst, int screenY); /* 168 */
-    int (*tkStateParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, int offset); /* 169 */
-    const char * (*tkStatePrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr); /* 170 */
-    int (*tkCanvasDashParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, int offset); /* 171 */
-    const char * (*tkCanvasDashPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr); /* 172 */
-    int (*tkOffsetParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, int offset); /* 173 */
-    const char * (*tkOffsetPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr); /* 174 */
-    int (*tkPixelParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, int offset); /* 175 */
-    const char * (*tkPixelPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr); /* 176 */
-    int (*tkOrientParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, int offset); /* 177 */
-    const char * (*tkOrientPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr); /* 178 */
-    int (*tkSmoothParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, int offset); /* 179 */
-    const char * (*tkSmoothPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, int offset, Tcl_FreeProc **freeProcPtr); /* 180 */
+    int (*tkStateParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset); /* 169 */
+    const char * (*tkStatePrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr); /* 170 */
+    int (*tkCanvasDashParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset); /* 171 */
+    const char * (*tkCanvasDashPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr); /* 172 */
+    int (*tkOffsetParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset); /* 173 */
+    const char * (*tkOffsetPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr); /* 174 */
+    int (*tkPixelParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset); /* 175 */
+    const char * (*tkPixelPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr); /* 176 */
+    int (*tkOrientParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset); /* 177 */
+    const char * (*tkOrientPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr); /* 178 */
+    int (*tkSmoothParseProc) (ClientData clientData, Tcl_Interp *interp, Tk_Window tkwin, const char *value, char *widgRec, TkSizeT offset); /* 179 */
+    const char * (*tkSmoothPrintProc) (ClientData clientData, Tk_Window tkwin, char *widgRec, TkSizeT offset, Tcl_FreeProc **freeProcPtr); /* 180 */
     void (*tkDrawAngledTextLayout) (Display *display, Drawable drawable, GC gc, Tk_TextLayout layout, int x, int y, double angle, int firstChar, int lastChar); /* 181 */
     void (*tkUnderlineAngledTextLayout) (Display *display, Drawable drawable, GC gc, Tk_TextLayout layout, int x, int y, double angle, int underline); /* 182 */
     int (*tkIntersectAngledTextLayout) (Tk_TextLayout layout, int x, int y, int width, int height, double angle); /* 183 */
diff --git a/generic/tkListbox.c b/generic/tkListbox.c
index ce5f350..6ea80ff 100644
--- a/generic/tkListbox.c
+++ b/generic/tkListbox.c
@@ -409,8 +409,8 @@ static void		ListboxComputeGeometry(Listbox *listPtr,
 			    int fontChanged, int maxIsStale, int updateGrid);
 static void		ListboxEventProc(ClientData clientData,
 			    XEvent *eventPtr);
-static int		ListboxFetchSelection(ClientData clientData,
-			    int offset, char *buffer, int maxBytes);
+static TkSizeT	ListboxFetchSelection(ClientData clientData,
+			    TkSizeT offset, char *buffer, TkSizeT maxBytes);
 static void		ListboxLostSelection(ClientData clientData);
 static void		GenerateListboxSelectEvent(Listbox *listPtr);
 static void		EventuallyRedrawRange(Listbox *listPtr,
@@ -3112,13 +3112,13 @@ ListboxSelect(
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 ListboxFetchSelection(
     ClientData clientData,	/* Information about listbox widget. */
-    int offset,			/* Offset within selection of first byte to be
+	TkSizeT offset,			/* Offset within selection of first byte to be
 				 * returned. */
     char *buffer,		/* Location in which to place selection. */
-    int maxBytes)		/* Maximum number of bytes to place at buffer,
+	TkSizeT maxBytes)		/* Maximum number of bytes to place at buffer,
 				 * not including terminating NULL
 				 * character. */
 {
@@ -3163,12 +3163,12 @@ ListboxFetchSelection(
      * Copy the requested portion of the selection to the buffer.
      */
 
-    if (length <= (TkSizeT)offset) {
+    if (length <= offset) {
 	count = 0;
     } else {
 	count = length - offset;
-	if (count > maxBytes) {
-	    count = maxBytes;
+	if (count > (int)maxBytes) {
+	    count = (int)maxBytes;
 	}
 	memcpy(buffer, Tcl_DStringValue(&selection) + offset, count);
     }
diff --git a/generic/tkPanedWindow.c b/generic/tkPanedWindow.c
index 297b335..5972f69 100644
--- a/generic/tkPanedWindow.c
+++ b/generic/tkPanedWindow.c
@@ -225,10 +225,10 @@ static void		DestroyOptionTables(ClientData clientData,
 			    Tcl_Interp *interp);
 static int		SetSticky(ClientData clientData, Tcl_Interp *interp,
 			    Tk_Window tkwin, Tcl_Obj **value, char *recordPtr,
-			    int internalOffset, char *oldInternalPtr,
+			    TkSizeT internalOffset, char *oldInternalPtr,
 			    int flags);
 static Tcl_Obj *	GetSticky(ClientData clientData, Tk_Window tkwin,
-			    char *recordPtr, int internalOffset);
+			    char *recordPtr, TkSizeT internalOffset);
 static void		RestoreSticky(ClientData clientData, Tk_Window tkwin,
 			    char *internalPtr, char *oldInternalPtr);
 static void		AdjustForSticky(int sticky, int cavityWidth,
@@ -236,7 +236,7 @@ static void		AdjustForSticky(int sticky, int cavityWidth,
 			    int *slaveWidthPtr, int *slaveHeightPtr);
 static void		MoveSash(PanedWindow *pwPtr, int sash, int diff);
 static int		ObjectIsEmpty(Tcl_Obj *objPtr);
-static void *	ComputeSlotAddress(void *recordPtr, size_t offset);
+static void *	ComputeSlotAddress(void *recordPtr, TkSizeT offset);
 static int		PanedWindowIdentifyCoords(PanedWindow *pwPtr,
 			    Tcl_Interp *interp, int x, int y);
 
@@ -2402,7 +2402,7 @@ GetSticky(
     ClientData dummy,
     Tk_Window tkwin,
     char *recordPtr,		/* Pointer to widget record. */
-    int internalOffset)		/* Offset within *recordPtr containing the
+    TkSizeT internalOffset)		/* Offset within *recordPtr containing the
 				 * sticky value. */
 {
     int sticky = *(int *)(recordPtr + internalOffset);
@@ -2456,7 +2456,7 @@ SetSticky(
 				 * We use a pointer to the pointer because we
 				 * may need to return a value (NULL). */
     char *recordPtr,		/* Pointer to storage for the widget record. */
-    int internalOffset,		/* Offset within *recordPtr at which the
+    TkSizeT internalOffset,		/* Offset within *recordPtr at which the
 				 * internal value is to be stored. */
     char *oldInternalPtr,	/* Pointer to storage for the old value. */
     int flags)			/* Flags for the option, set Tk_SetOptions. */
@@ -3035,9 +3035,9 @@ ObjectIsEmpty(
 static void *
 ComputeSlotAddress(
     void *recordPtr,	/* Pointer to the start of a record. */
-    size_t offset)		/* Offset of a slot within that record; may be -1. */
+	TkSizeT offset)		/* Offset of a slot within that record; may be TCL_INDEX_NONE. */
 {
-    if (offset != (size_t)-1) {
+    if (offset != TCL_INDEX_NONE) {
 	return (char *)recordPtr + offset;
     } else {
 	return NULL;
diff --git a/generic/tkRectOval.c b/generic/tkRectOval.c
index a820411..76bf03b 100644
--- a/generic/tkRectOval.c
+++ b/generic/tkRectOval.c
@@ -47,7 +47,7 @@ static const Tk_CustomOption stateOption = {
     TkStateParseProc, TkStatePrintProc, INT2PTR(2)
 };
 static const Tk_CustomOption tagsOption = {
-    Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
+    TkCanvasTagsParseProc, TkCanvasTagsPrintProc, NULL
 };
 static const Tk_CustomOption dashOption = {
     TkCanvasDashParseProc, TkCanvasDashPrintProc, NULL
diff --git a/generic/tkSelect.c b/generic/tkSelect.c
index a6548b6..3ad2820 100644
--- a/generic/tkSelect.c
+++ b/generic/tkSelect.c
@@ -59,8 +59,8 @@ static Tcl_ThreadDataKey dataKey;
  * Forward declarations for functions defined in this file:
  */
 
-static int		HandleTclCommand(ClientData clientData,
-			    int offset, char *buffer, int maxBytes);
+static TkSizeT	HandleTclCommand(ClientData clientData,
+			    TkSizeT offset, char *buffer, TkSizeT maxBytes);
 static void		LostSelection(ClientData clientData);
 static int		SelGetProc(ClientData clientData,
 			    Tcl_Interp *interp, const char *portion);
@@ -1319,13 +1319,13 @@ SelGetProc(
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 HandleTclCommand(
     ClientData clientData,	/* Information about command to execute. */
-    int offset,			/* Return selection bytes starting at this
+	TkSizeT offset,			/* Return selection bytes starting at this
 				 * offset. */
     char *buffer,		/* Place to store converted selection. */
-    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+	TkSizeT maxBytes)		/* Maximum # of bytes to store at buffer. */
 {
     CommandInfo *cmdInfoPtr = (CommandInfo *)clientData;
     int length;
@@ -1349,7 +1349,7 @@ HandleTclCommand(
      * character.
      */
 
-    if (offset == cmdInfoPtr->byteOffset) {
+    if ((int)offset == cmdInfoPtr->byteOffset) {
 	charOffset = cmdInfoPtr->charOffset;
 	extraBytes = strlen(cmdInfoPtr->buffer);
 	if (extraBytes > 0) {
@@ -1370,7 +1370,7 @@ HandleTclCommand(
      */
 
     command = Tcl_ObjPrintf("%s %d %d",
-	    cmdInfoPtr->command, charOffset, maxBytes);
+	    cmdInfoPtr->command, charOffset, (int)maxBytes);
     Tcl_IncrRefCount(command);
 
     /*
@@ -1387,7 +1387,7 @@ HandleTclCommand(
 	 */
 
 	string = Tcl_GetStringFromObj(Tcl_GetObjResult(interp), &length);
-	count = (length > maxBytes) ? maxBytes : length;
+	count = (length > (int)maxBytes) ? (int)maxBytes : length;
 	memcpy(buffer, string, count);
 	buffer[count] = '\0';
 
@@ -1397,7 +1397,7 @@ HandleTclCommand(
 	 */
 
 	if (cmdInfoPtr->interp != NULL) {
-	    if (length <= maxBytes) {
+	    if (length <= (int)maxBytes) {
 		cmdInfoPtr->charOffset += Tcl_NumUtfChars(string, -1);
 		cmdInfoPtr->buffer[0] = '\0';
 	    } else {
diff --git a/generic/tkSelect.h b/generic/tkSelect.h
index 405cbea..c2d153b 100644
--- a/generic/tkSelect.h
+++ b/generic/tkSelect.h
@@ -107,7 +107,7 @@ typedef struct TkSelRetrievalInfo {
 
 typedef struct TkClipboardBuffer {
     char *buffer;		/* Null terminated data buffer. */
-    size_t length;		/* Length of string in buffer. */
+    TkSizeT length;		/* Length of string in buffer. */
     struct TkClipboardBuffer *nextPtr;
 				/* Next in list of buffers. NULL means end of
 				 * list . */
diff --git a/generic/tkStubInit.c b/generic/tkStubInit.c
index 1942173..8b98928 100644
--- a/generic/tkStubInit.c
+++ b/generic/tkStubInit.c
@@ -100,6 +100,12 @@ static Tk_Style Tk_GetStyleFromObj(Tcl_Obj *obj)
 #define TkMacOSXInitAppleEvents_ TkMacOSXInitAppleEvents
 #define TkGenWMConfigureEvent_ TkGenWMConfigureEvent
 #define TkGenerateActivateEvents_ TkGenerateActivateEvents
+#define Tk_CanvasTagsParseProc \
+		(int (*) (void *, Tcl_Interp *,Tk_Window, const char *, char *, \
+		int offset))(void *)TkCanvasTagsParseProc
+#define Tk_CanvasTagsPrintProc \
+		(const char *(*) (void *,Tk_Window, char *, int, \
+		Tcl_FreeProc **))(void *)TkCanvasTagsPrintProc
 
 #ifdef _WIN32
 
diff --git a/generic/tkTest.c b/generic/tkTest.c
index 97b33fc..1f76fe2 100644
--- a/generic/tkTest.c
+++ b/generic/tkTest.c
@@ -186,19 +186,10 @@ static int		TestmetricsObjCmd(ClientData dummy,
 static int		TestobjconfigObjCmd(ClientData dummy,
 			    Tcl_Interp *interp, int objc,
 			    Tcl_Obj * const objv[]);
-static int		CustomOptionSet(ClientData clientData,
-			    Tcl_Interp *interp, Tk_Window tkwin,
-			    Tcl_Obj **value, char *recordPtr,
-			    int internalOffset, char *saveInternalPtr,
-			    int flags);
-static Tcl_Obj *	CustomOptionGet(ClientData clientData,
-			    Tk_Window tkwin, char *recordPtr,
-			    int internalOffset);
-static void		CustomOptionRestore(ClientData clientData,
-			    Tk_Window tkwin, char *internalPtr,
-			    char *saveInternalPtr);
-static void		CustomOptionFree(ClientData clientData,
-			    Tk_Window tkwin, char *internalPtr);
+static Tk_CustomOptionSetProc CustomOptionSet;
+static Tk_CustomOptionGetProc CustomOptionGet;
+static Tk_CustomOptionRestoreProc CustomOptionRestore;
+static Tk_CustomOptionFreeProc CustomOptionFree;
 static int		TestpropObjCmd(ClientData dummy,
 			    Tcl_Interp *interp, int objc,
 			    Tcl_Obj * const objv[]);
@@ -2047,8 +2038,7 @@ TestwrapperObjCmd(
  *		CustomOptionSet		Sets option value to new setting.
  *		CustomOptionGet		Creates a new Tcl_Obj.
  *		CustomOptionRestore	Resets option value to original value.
- *		CustomOptionFree	Free storage for internal rep of
- *					option.
+ *		CustomOptionFree	Free storage for internal rep of option.
  *
  *----------------------------------------------------------------------
  */
@@ -2060,7 +2050,7 @@ CustomOptionSet(
     Tk_Window tkwin,
     Tcl_Obj **value,
     char *recordPtr,
-    int internalOffset,
+	TkSizeT internalOffset,
     char *saveInternalPtr,
     int flags)
 {
@@ -2071,7 +2061,7 @@ CustomOptionSet(
 
     objEmpty = 0;
 
-    if (internalOffset != -1) {
+    if (internalOffset != TCL_INDEX_NONE) {
 	internalPtr = recordPtr + internalOffset;
     } else {
 	internalPtr = NULL;
@@ -2121,7 +2111,7 @@ CustomOptionGet(
     ClientData dummy,
     Tk_Window tkwin,
     char *recordPtr,
-    int internalOffset)
+	TkSizeT internalOffset)
 {
     (void)dummy;
     (void)tkwin;
diff --git a/generic/tkText.c b/generic/tkText.c
index 882225f..36b5ae2 100644
--- a/generic/tkText.c
+++ b/generic/tkText.c
@@ -96,11 +96,11 @@ static const char *const insertUnfocussedStrings[] = {
 static int		SetLineStartEnd(ClientData clientData,
 			    Tcl_Interp *interp, Tk_Window tkwin,
 			    Tcl_Obj **value, char *recordPtr,
-			    int internalOffset, char *oldInternalPtr,
+			    TkSizeT internalOffset, char *oldInternalPtr,
 			    int flags);
 static Tcl_Obj *	GetLineStartEnd(ClientData clientData,
 			    Tk_Window tkwin, char *recordPtr,
-			    int internalOffset);
+			    TkSizeT internalOffset);
 static void		RestoreLineStartEnd(ClientData clientData,
 			    Tk_Window tkwin, char *internalPtr,
 			    char *oldInternalPtr);
@@ -365,8 +365,8 @@ static int		CreateWidget(TkSharedText *sharedPtr, Tk_Window tkwin,
 			    int objc, Tcl_Obj *const objv[]);
 static void		TextEventProc(ClientData clientData,
 			    XEvent *eventPtr);
-static int		TextFetchSelection(ClientData clientData, int offset,
-			    char *buffer, int maxBytes);
+static TkSizeT	TextFetchSelection(ClientData clientData, TkSizeT offset,
+			    char *buffer, TkSizeT maxBytes);
 static int		TextIndexSortProc(const void *first,
 			    const void *second);
 static int		TextInsertCmd(TkSharedText *sharedTextPtr,
@@ -3413,13 +3413,13 @@ DeleteIndexRange(
  *----------------------------------------------------------------------
  */
 
-static int
+static TkSizeT
 TextFetchSelection(
     ClientData clientData,	/* Information about text widget. */
-    int offset,			/* Offset within selection of first character
+	TkSizeT offset,			/* Offset within selection of first character
 				 * to be returned. */
     char *buffer,		/* Location in which to place selection. */
-    int maxBytes)		/* Maximum number of bytes to place at buffer,
+	TkSizeT maxBytes)		/* Maximum number of bytes to place at buffer,
 				 * not including terminating NULL
 				 * character. */
 {
@@ -3484,13 +3484,15 @@ TextFetchSelection(
 	 */
 
 	while (1) {
+	    TkSizeT offsetInSeg1;
 	    if (maxBytes == 0) {
 		goto fetchDone;
 	    }
-	    segPtr = TkTextIndexToSeg(&textPtr->selIndex, &offsetInSeg);
+	    segPtr = TkTextIndexToSeg(&textPtr->selIndex, &offsetInSeg1);
+	    offsetInSeg = offsetInSeg1;
 	    chunkSize = segPtr->size - offsetInSeg;
-	    if (chunkSize > maxBytes) {
-		chunkSize = maxBytes;
+	    if (chunkSize > (int)maxBytes) {
+		chunkSize = (int)maxBytes;
 	    }
 	    if (textPtr->selIndex.linePtr == search.curIndex.linePtr) {
 		int leftInRange;
@@ -4095,14 +4097,14 @@ TextSearchIndexInLine(
 	if ((segPtr->typePtr == &tkTextCharType) &&
 		(searchSpecPtr->searchElide
 		|| !TkTextIsElided(textPtr, &curIndex, NULL))) {
-	    if (leftToScan < segPtr->size) {
+	    if (leftToScan < (int)segPtr->size) {
 		if (searchSpecPtr->exact) {
 		    index += leftToScan;
 		} else {
 		    index += Tcl_NumUtfChars(segPtr->body.chars, leftToScan);
 		}
 	    } else if (searchSpecPtr->exact) {
-		index += segPtr->size;
+		index += (int)segPtr->size;
 	    } else {
 		index += Tcl_NumUtfChars(segPtr->body.chars, -1);
 	    }
@@ -4362,7 +4364,7 @@ TextSearchFoundMatch(
 		}
 	    } else {
 		if (searchSpecPtr->exact) {
-		    leftToScan -= segPtr->size;
+		    leftToScan -= (int)segPtr->size;
 		} else {
 		    leftToScan -= Tcl_NumUtfChars(segPtr->body.chars, -1);
 		}
@@ -5433,7 +5435,7 @@ TextGetText(
 
     if (TkTextIndexCmp(indexPtr1, indexPtr2) < 0) {
 	while (1) {
-	    int offset;
+	    TkSizeT offset;
 	    TkTextSegment *segPtr = TkTextIndexToSeg(&tmpIndex, &offset);
 	    int last = segPtr->size, last2;
 
@@ -6778,14 +6780,14 @@ GetLineStartEnd(
     ClientData dummy,
     Tk_Window tkwin,
     char *recordPtr,		/* Pointer to widget record. */
-    int internalOffset)		/* Offset within *recordPtr containing the
+    TkSizeT internalOffset)		/* Offset within *recordPtr containing the
 				 * line value. */
 {
     TkTextLine *linePtr = *(TkTextLine **)(recordPtr + internalOffset);
     (void)dummy;
     (void)tkwin;
 
-    if (linePtr == NULL) {
+    if ((internalOffset == TCL_INDEX_NONE) || (recordPtr == NULL)) {
 	return Tcl_NewObj();
     }
     return Tcl_NewWideIntObj(1 + TkBTreeLinesTo(NULL, linePtr));
@@ -6819,7 +6821,7 @@ SetLineStartEnd(
 				 * We use a pointer to the pointer because we
 				 * may need to return a value (NULL). */
     char *recordPtr,		/* Pointer to storage for the widget record. */
-    int internalOffset,		/* Offset within *recordPtr at which the
+    TkSizeT internalOffset,		/* Offset within *recordPtr at which the
 				 * internal value is to be stored. */
     char *oldInternalPtr,	/* Pointer to storage for the old value. */
     int flags)			/* Flags for the option, set Tk_SetOptions. */
@@ -6830,7 +6832,7 @@ SetLineStartEnd(
     (void)dummy;
     (void)tkwin;
 
-    if (internalOffset >= 0) {
+    if (internalOffset != TCL_INDEX_NONE) {
 	internalPtr = (char *)recordPtr + internalOffset;
     } else {
 	internalPtr = NULL;
diff --git a/generic/tkText.h b/generic/tkText.h
index 8fb4134..52abc8c 100644
--- a/generic/tkText.h
+++ b/generic/tkText.h
@@ -165,7 +165,7 @@ typedef struct TkTextSegment {
     struct TkTextSegment *nextPtr;
 				/* Next in list of segments for this line, or
 				 * NULL for end of list. */
-    int size;			/* Size of this segment (# of bytes of index
+    TkSizeT size;			/* Size of this segment (# of bytes of index
 				 * space it occupies). */
     union {
 	char chars[2];		/* Characters that make up character info.
@@ -847,7 +847,7 @@ typedef struct TkText {
  */
 
 typedef TkTextSegment *	Tk_SegSplitProc(struct TkTextSegment *segPtr,
-			    int index);
+			    TkSizeT index);
 typedef int		Tk_SegDeleteProc(struct TkTextSegment *segPtr,
 			    TkTextLine *linePtr, int treeGone);
 typedef TkTextSegment *	Tk_SegCleanupProc(struct TkTextSegment *segPtr,
@@ -856,8 +856,8 @@ typedef void		Tk_SegLineChangeProc(struct TkTextSegment *segPtr,
 			    TkTextLine *linePtr);
 typedef int		Tk_SegLayoutProc(struct TkText *textPtr,
 			    struct TkTextIndex *indexPtr,
-			    TkTextSegment *segPtr, int offset, int maxX,
-			    int maxChars, int noCharsYet, TkWrapMode wrapMode,
+			    TkTextSegment *segPtr, TkSizeT offset, int maxX,
+				TkSizeT maxChars, int noCharsYet, TkWrapMode wrapMode,
 			    struct TkTextDispChunk *chunkPtr);
 typedef void		Tk_SegCheckProc(TkTextSegment *segPtr,
 			    TkTextLine *linePtr);
@@ -1060,7 +1060,7 @@ MODULE_SCOPE int	TkTextIndexBbox(TkText *textPtr,
 			    int *widthPtr, int *heightPtr, int *charWidthPtr);
 MODULE_SCOPE int	TkTextCharLayoutProc(TkText *textPtr,
 			    TkTextIndex *indexPtr, TkTextSegment *segPtr,
-			    int offset, int maxX, int maxChars, int noBreakYet,
+			    TkSizeT offset, int maxX, TkSizeT maxChars, int noBreakYet,
 			    TkWrapMode wrapMode, TkTextDispChunk *chunkPtr);
 MODULE_SCOPE void	TkTextCreateDInfo(TkText *textPtr);
 MODULE_SCOPE int	TkTextDLineInfo(TkText *textPtr,
@@ -1106,7 +1106,7 @@ MODULE_SCOPE void	TkTextIndexOfX(TkText *textPtr, int x,
 MODULE_SCOPE int	TkTextIndexYPixels(TkText *textPtr,
 			    const TkTextIndex *indexPtr);
 MODULE_SCOPE TkTextSegment *TkTextIndexToSeg(const TkTextIndex *indexPtr,
-			    int *offsetPtr);
+			    TkSizeT *offsetPtr);
 MODULE_SCOPE void	TkTextLostSelection(ClientData clientData);
 MODULE_SCOPE TkTextIndex *TkTextMakeCharIndex(TkTextBTree tree, TkText *textPtr,
 			    int lineIndex, int charIndex,
diff --git a/generic/tkTextBTree.c b/generic/tkTextBTree.c
index 071ae59..5ce7a99 100644
--- a/generic/tkTextBTree.c
+++ b/generic/tkTextBTree.c
@@ -161,7 +161,7 @@ static int		CharDeleteProc(TkTextSegment *segPtr,
 			    TkTextLine *linePtr, int treeGone);
 static TkTextSegment *	CharCleanupProc(TkTextSegment *segPtr,
 			    TkTextLine *linePtr);
-static TkTextSegment *	CharSplitProc(TkTextSegment *segPtr, int index);
+static TkTextSegment *	CharSplitProc(TkTextSegment *segPtr, TkSizeT index);
 static void		CheckNodeConsistency(Node *nodePtr, int references);
 static void		CleanupLine(TkTextLine *linePtr);
 static void		DeleteSummaries(Summary *tagPtr);
@@ -1197,7 +1197,7 @@ SplitSeg(
     segPtr = linePtr->segPtr;
 
     while (segPtr != NULL) {
-	if (segPtr->size > count) {
+	if (segPtr->size > (TkSizeT)count) {
 	    if (count == 0) {
 		return prevPtr;
 	    }
@@ -2654,7 +2654,7 @@ TkBTreeStartSearch(
 				/* Where to store information about search's
 				 * progress. */
 {
-    int offset;
+    TkSizeT offset;
     TkTextIndex index0;		/* First index of the tag. */
     TkTextSegment *seg0Ptr;	/* First segment of the tag. */
 
@@ -2750,7 +2750,7 @@ TkBTreeStartSearchBack(
 				/* Where to store information about search's
 				 * progress. */
 {
-    int offset;
+	TkSizeT offset;
     TkTextIndex index0;		/* Last index of the tag. */
     TkTextIndex backOne;	/* One character before starting index. */
     TkTextSegment *seg0Ptr;	/* Last segment of the tag. */
@@ -3244,7 +3244,7 @@ TkBTreeCharTagged(
 
     toggleSegPtr = NULL;
     for (index = 0, segPtr = indexPtr->linePtr->segPtr;
-	    (index + segPtr->size) <= indexPtr->byteIndex;
+	    (index + (int)segPtr->size) <= indexPtr->byteIndex;
 	    index += segPtr->size, segPtr = segPtr->nextPtr) {
 	if (((segPtr->typePtr == &tkTextToggleOnType)
 		|| (segPtr->typePtr == &tkTextToggleOffType))
@@ -3364,7 +3364,7 @@ TkBTreeGetTags(
     linePtr = indexPtr->linePtr;
     index = 0;
     segPtr = linePtr->segPtr;
-    while ((index + segPtr->size) <= indexPtr->byteIndex) {
+    while ((index + (int)segPtr->size) <= indexPtr->byteIndex) {
 	if ((segPtr->typePtr == &tkTextToggleOnType)
 		|| (segPtr->typePtr == &tkTextToggleOffType)) {
 	    IncCount(segPtr->body.toggle.tagPtr, 1, &tagInfo);
@@ -3528,7 +3528,7 @@ TkTextIsElided(
     index = 0;
     linePtr = indexPtr->linePtr;
     segPtr = linePtr->segPtr;
-    while ((index + segPtr->size) <= indexPtr->byteIndex) {
+    while ((index + (int)segPtr->size) <= indexPtr->byteIndex) {
 	if ((segPtr->typePtr == &tkTextToggleOnType)
 		|| (segPtr->typePtr == &tkTextToggleOffType)) {
 	    tagPtr = segPtr->body.toggle.tagPtr;
@@ -3865,7 +3865,7 @@ TkBTreeCheck(
     }
     if (segPtr->size != 1) {
 	Tcl_Panic("TkBTreeCheck: last line has wrong # characters: %d",
-		segPtr->size);
+		(int)segPtr->size);
     }
     if ((segPtr->body.chars[0] != '\n') || (segPtr->body.chars[1] != 0)) {
 	Tcl_Panic("TkBTreeCheck: last line had bad value: %s",
@@ -4549,7 +4549,7 @@ TkBTreeNumPixels(
 static TkTextSegment *
 CharSplitProc(
     TkTextSegment *segPtr,	/* Pointer to segment to split. */
-    int index)			/* Position within segment at which to
+    TkSizeT index)			/* Position within segment at which to
 				 * split. */
 {
     TkTextSegment *newPtr1, *newPtr2;
@@ -4675,10 +4675,10 @@ CharCheckProc(
      * to each other: they should be merged together.
      */
 
-    if (segPtr->size <= 0) {
+    if (segPtr->size + 1 <= 1) {
 	Tcl_Panic("CharCheckProc: segment has size <= 0");
     }
-    if (strlen(segPtr->body.chars) != (size_t) segPtr->size) {
+    if (strlen(segPtr->body.chars) != (size_t)segPtr->size) {
 	Tcl_Panic("CharCheckProc: segment has wrong size");
     }
     if (segPtr->nextPtr == NULL) {
diff --git a/generic/tkTextDisp.c b/generic/tkTextDisp.c
index 2dfe964..6917292 100644
--- a/generic/tkTextDisp.c
+++ b/generic/tkTextDisp.c
@@ -1173,7 +1173,8 @@ LayoutDLine(
 				/* Pointer to last chunk in display lines with
 				 * numBytes > 0. Used to drop 0-sized chunks
 				 * from the end of the line. */
-    int byteOffset, ascent, descent, code, elide, elidesize;
+    TkSizeT byteOffset;
+    int ascent, descent, code, elide, elidesize;
     StyleValues *sValuePtr;
     TkTextElideInfo info;	/* Keep track of elide state. */
 
@@ -1213,7 +1214,7 @@ LayoutDLine(
     if (elide && indexPtr->byteIndex == 0) {
 	maxBytes = 0;
 	for (segPtr = info.segPtr; segPtr != NULL; segPtr = segPtr->nextPtr) {
-	    if (segPtr->size > 0) {
+	    if (segPtr->size + 1 > 1) {
 		if (elide == 0) {
 		    /*
 		     * We toggled a tag and the elide state changed to
@@ -1334,7 +1335,7 @@ LayoutDLine(
   connectNextLogicalLine:
     byteOffset = curIndex.byteIndex;
     segPtr = curIndex.linePtr->segPtr;
-    while ((byteOffset > 0) && (byteOffset >= segPtr->size)) {
+    while ((byteOffset + 1 > 1) && (byteOffset + 1 >= segPtr->size + 1)) {
 	byteOffset -= segPtr->size;
 	segPtr = segPtr->nextPtr;
 
@@ -1374,7 +1375,7 @@ LayoutDLine(
 	if (elide && (lastChunkPtr != NULL)
 		&& (lastChunkPtr->displayProc == NULL /*ElideDisplayProc*/)) {
 	    elidesize = segPtr->size - byteOffset;
-	    if (elidesize > 0) {
+	    if (segPtr->size + 1 > byteOffset + 1) {
 		curIndex.byteIndex += elidesize;
 		lastChunkPtr->numBytes += elidesize;
 		breakByteOffset = lastChunkPtr->breakIndex
@@ -7603,11 +7604,11 @@ TkTextCharLayoutProc(
     TkTextIndex *indexPtr,	/* Index of first character to lay out
 				 * (corresponds to segPtr and offset). */
     TkTextSegment *segPtr,	/* Segment being layed out. */
-    int byteOffset,		/* Byte offset within segment of first
+    TkSizeT byteOffset,		/* Byte offset within segment of first
 				 * character to consider. */
     int maxX,			/* Chunk must not occupy pixels at this
 				 * position or higher. */
-    int maxBytes,		/* Chunk must not include more than this many
+	TkSizeT maxBytes,		/* Chunk must not include more than this many
 				 * characters. */
     int noCharsYet,		/* Non-zero means no characters have been
 				 * assigned to this display line yet. */
@@ -7684,7 +7685,7 @@ TkTextCharLayoutProc(
 	    chunkPtr->x, maxX, TK_ISOLATE_END, &nextX);
 #endif /* TK_LAYOUT_WITH_BASE_CHUNKS */
 
-    if (bytesThatFit < maxBytes) {
+    if ((TkSizeT)bytesThatFit + 1 <= maxBytes) {
 	if ((bytesThatFit == 0) && noCharsYet) {
 	    int ch;
 	    int chLen = TkUtfToUniChar(p, &ch);
diff --git a/generic/tkTextImage.c b/generic/tkTextImage.c
index ccdfda6..ef79376 100644
--- a/generic/tkTextImage.c
+++ b/generic/tkTextImage.c
@@ -43,7 +43,7 @@ static void		EmbImageDisplayProc(TkText *textPtr,
 			    Drawable dst, int screenY);
 static int		EmbImageLayoutProc(TkText *textPtr,
 			    TkTextIndex *indexPtr, TkTextSegment *segPtr,
-			    int offset, int maxX, int maxChars,
+			    TkSizeT offset, int maxX, TkSizeT maxChars,
 			    int noCharsYet, TkWrapMode wrapMode,
 			    TkTextDispChunk *chunkPtr);
 static void		EmbImageProc(ClientData clientData, int x, int y,
@@ -533,11 +533,11 @@ EmbImageLayoutProc(
     TkText *textPtr,		/* Text widget being layed out. */
     TkTextIndex *indexPtr,	/* Identifies first character in chunk. */
     TkTextSegment *eiPtr,	/* Segment corresponding to indexPtr. */
-    int offset,			/* Offset within segPtr corresponding to
+	TkSizeT offset,			/* Offset within segPtr corresponding to
 				 * indexPtr (always 0). */
     int maxX,			/* Chunk must not occupy pixels at this
 				 * position or higher. */
-    int maxChars,		/* Chunk must not include more than this many
+	TkSizeT maxChars,		/* Chunk must not include more than this many
 				 * characters. */
     int noCharsYet,		/* Non-zero means no characters have been
 				 * assigned to this line yet. */
@@ -631,7 +631,7 @@ EmbImageCheckProc(
     }
     if (eiPtr->size != 1) {
 	Tcl_Panic("EmbImageCheckProc: embedded image has size %d",
-		eiPtr->size);
+		(int)eiPtr->size);
     }
 }
 
diff --git a/generic/tkTextIndex.c b/generic/tkTextIndex.c
index 70a53ae..4a80844 100644
--- a/generic/tkTextIndex.c
+++ b/generic/tkTextIndex.c
@@ -425,7 +425,7 @@ TkTextMakeByteIndex(
 	    indexPtr->byteIndex = index - sizeof(char);
 	    break;
 	}
-	if (index + segPtr->size > byteIndex) {
+	if (index + (int)segPtr->size > byteIndex) {
 	    indexPtr->byteIndex = byteIndex;
 	    if ((byteIndex > index) && (segPtr->typePtr == &tkTextCharType)) {
 		/*
@@ -531,7 +531,7 @@ TkTextMakeCharIndex(
 		index += offset;
 	    }
 	} else {
-	    if (charIndex < segPtr->size) {
+	    if (charIndex < (int)segPtr->size) {
 		indexPtr->byteIndex = index;
 		break;
 	    }
@@ -565,11 +565,11 @@ TkTextMakeCharIndex(
 TkTextSegment *
 TkTextIndexToSeg(
     const TkTextIndex *indexPtr,/* Text index. */
-    int *offsetPtr)		/* Where to store offset within segment, or
+    TkSizeT *offsetPtr)		/* Where to store offset within segment, or
 				 * NULL if offset isn't wanted. */
 {
     TkTextSegment *segPtr;
-    int offset;
+    TkSizeT offset;
 
     for (offset = indexPtr->byteIndex, segPtr = indexPtr->linePtr->segPtr;
 	    offset >= segPtr->size;
@@ -1049,7 +1049,7 @@ TkTextPrintIndex(
 	    linePtr = TkBTreeNextLine(NULL, linePtr);
 	    segPtr = linePtr->segPtr;
 	}
-	if (numBytes <= segPtr->size) {
+	if (numBytes <= (int)segPtr->size) {
 	    break;
 	}
 	if (segPtr->typePtr == &tkTextCharType) {
@@ -1488,7 +1488,7 @@ TkTextIndexForwChars(
     TkTextLine *linePtr;
     TkTextSegment *segPtr;
     TkTextElideInfo *infoPtr = NULL;
-    int byteOffset;
+    TkSizeT byteOffset;
     char *start, *end, *p;
     int ch;
     int elide = 0;
@@ -1597,7 +1597,7 @@ TkTextIndexForwChars(
 			charCount--;
 		    }
 		} else if (type & COUNT_INDICES) {
-		    if (charCount < segPtr->size - byteOffset) {
+		    if (charCount + byteOffset < segPtr->size) {
 			dstPtr->byteIndex += charCount;
 			goto forwardCharDone;
 		    }
@@ -1676,7 +1676,7 @@ IndexCountBytesOrdered(
 				/* Index describing location of last character
 				 * at which to stop the count. */
 {
-    int byteCount, offset;
+    TkSizeT byteCount, offset;
     TkTextSegment *segPtr, *segPtr1;
     TkTextLine *linePtr;
 
@@ -1753,7 +1753,8 @@ TkTextIndexCount(
     TkTextLine *linePtr1;
     TkTextSegment *segPtr, *seg2Ptr = NULL;
     TkTextElideInfo *infoPtr = NULL;
-    int byteOffset, maxBytes, count = 0, elide = 0;
+    TkSizeT byteOffset, maxBytes, count = 0;
+    int elide = 0;
     int checkElided = (type & COUNT_DISPLAY);
 
     /*
@@ -1843,13 +1844,13 @@ TkTextIndexCount(
 	    }
 
 	    if (segPtr->typePtr == &tkTextCharType) {
-		int byteLen = segPtr->size - byteOffset;
+		TkSizeT byteLen = segPtr->size - byteOffset;
 		unsigned char *str = (unsigned char *)
 			segPtr->body.chars + byteOffset;
-		int i;
+		TkSizeT i;
 
 		if (segPtr == seg2Ptr) {
-		    if (byteLen > (maxBytes - byteOffset)) {
+		    if (byteLen + byteOffset > maxBytes) {
 			byteLen = maxBytes - byteOffset;
 		    }
 		}
@@ -1876,10 +1877,10 @@ TkTextIndexCount(
 		}
 	    } else {
 		if (type & COUNT_INDICES) {
-		    int byteLen = segPtr->size - byteOffset;
+		    TkSizeT byteLen = segPtr->size - byteOffset;
 
 		    if (segPtr == seg2Ptr) {
-			if (byteLen > (maxBytes - byteOffset)) {
+			if (byteLen + byteOffset > maxBytes) {
 			    byteLen = maxBytes - byteOffset;
 			}
 		    }
@@ -2055,7 +2056,7 @@ TkTextIndexBackChars(
 		linePtr = TkBTreeNextLine(NULL, linePtr);
 		segPtr = linePtr->segPtr;
 	    }
-	    if (segSize <= segPtr->size) {
+	    if (segSize <= (int)segPtr->size) {
 		break;
 	    }
 	    segSize -= segPtr->size;
@@ -2296,7 +2297,7 @@ StartEnd(
     } else if ((*string == 'w') && (strncmp(string, "wordend", length) == 0)
 	    && (length >= 5)) {
 	int firstChar = 1;
-	int offset;
+	TkSizeT offset;
 
 	/*
 	 * If the current character isn't part of a word then just move
@@ -2339,7 +2340,7 @@ StartEnd(
     } else if ((*string == 'w') && (strncmp(string, "wordstart", length) == 0)
 	    && (length >= 5)) {
 	int firstChar = 1;
-	int offset;
+	TkSizeT offset;
 
 	if (modifier == TKINDEX_DISPLAY) {
 	    TkTextIndexForwChars(textPtr, indexPtr, 0, indexPtr,
@@ -2364,7 +2365,7 @@ StartEnd(
 		if (!Tcl_UniCharIsWordChar(ch)) {
 		    break;
 		}
-		if (offset > 0) {
+		if (offset + 1 > 1) {
 		    chSize = (segPtr->body.chars + offset
 			    - TkUtfPrev(segPtr->body.chars + offset,
 			    segPtr->body.chars));
@@ -2383,7 +2384,7 @@ StartEnd(
                 indexPtr->byteIndex -= chSize;
             }
             offset -= chSize;
-	    if (offset < 0) {
+	    if ((int)offset < 0) {
 		if (indexPtr->byteIndex == 0) {
 		    goto done;
 		}
diff --git a/generic/tkTextMark.c b/generic/tkTextMark.c
index 11acf37..8eceda9 100644
--- a/generic/tkTextMark.c
+++ b/generic/tkTextMark.c
@@ -36,8 +36,8 @@ static TkTextSegment *	MarkCleanupProc(TkTextSegment *segPtr,
 static void		MarkCheckProc(TkTextSegment *segPtr,
 			    TkTextLine *linePtr);
 static int		MarkLayoutProc(TkText *textPtr, TkTextIndex *indexPtr,
-			    TkTextSegment *segPtr, int offset, int maxX,
-			    int maxChars, int noCharsYet, TkWrapMode wrapMode,
+			    TkTextSegment *segPtr, TkSizeT offset, int maxX,
+			    TkSizeT maxChars, int noCharsYet, TkWrapMode wrapMode,
 			    TkTextDispChunk *chunkPtr);
 static int		MarkFindNext(Tcl_Interp *interp,
 			    TkText *textPtr, Tcl_Obj *markName);
@@ -564,11 +564,11 @@ MarkLayoutProc(
     TkText *textPtr,		/* Text widget being layed out. */
     TkTextIndex *indexPtr,	/* Identifies first character in chunk. */
     TkTextSegment *segPtr,	/* Segment corresponding to indexPtr. */
-    int offset,			/* Offset within segPtr corresponding to
+	TkSizeT offset,			/* Offset within segPtr corresponding to
 				 * indexPtr (always 0). */
     int maxX,			/* Chunk must not occupy pixels at this
 				 * position or higher. */
-    int maxChars,		/* Chunk must not include more than this many
+	TkSizeT maxChars,		/* Chunk must not include more than this many
 				 * characters. */
     int noCharsYet,		/* Non-zero means no characters have been
 				 * assigned to this line yet. */
diff --git a/generic/tkTextWind.c b/generic/tkTextWind.c
index d9c77d1..b046076 100644
--- a/generic/tkTextWind.c
+++ b/generic/tkTextWind.c
@@ -57,7 +57,7 @@ static int		EmbWinDeleteProc(TkTextSegment *segPtr,
 			    TkTextLine *linePtr, int treeGone);
 static int		EmbWinLayoutProc(TkText *textPtr,
 			    TkTextIndex *indexPtr, TkTextSegment *segPtr,
-			    int offset, int maxX, int maxChars,int noCharsYet,
+			    TkSizeT offset, int maxX, TkSizeT maxChars,int noCharsYet,
 			    TkWrapMode wrapMode, TkTextDispChunk *chunkPtr);
 static void		EmbWinStructureProc(ClientData clientData,
 			    XEvent *eventPtr);
@@ -822,11 +822,11 @@ EmbWinLayoutProc(
     TkText *textPtr,		/* Text widget being layed out. */
     TkTextIndex *indexPtr,	/* Identifies first character in chunk. */
     TkTextSegment *ewPtr,	/* Segment corresponding to indexPtr. */
-    int offset,			/* Offset within segPtr corresponding to
+	TkSizeT offset,			/* Offset within segPtr corresponding to
 				 * indexPtr (always 0). */
     int maxX,			/* Chunk must not occupy pixels at this
 				 * position or higher. */
-    int maxChars,		/* Chunk must not include more than this many
+	TkSizeT maxChars,		/* Chunk must not include more than this many
 				 * characters. */
     int noCharsYet,		/* Non-zero means no characters have been
 				 * assigned to this line yet. */
@@ -1063,7 +1063,7 @@ EmbWinCheckProc(
 	Tcl_Panic("EmbWinCheckProc: embedded window is last segment in line");
     }
     if (ewPtr->size != 1) {
-	Tcl_Panic("EmbWinCheckProc: embedded window has size %d", ewPtr->size);
+	Tcl_Panic("EmbWinCheckProc: embedded window has size %d", (int)ewPtr->size);
     }
 }
 
diff --git a/generic/tkUtil.c b/generic/tkUtil.c
index 01155c9..5a970c0 100644
--- a/generic/tkUtil.c
+++ b/generic/tkUtil.c
@@ -51,7 +51,7 @@ TkStateParseProc(
     TCL_UNUSED(Tk_Window),		/* Window containing canvas widget. */
     const char *value,		/* Value of option. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item. */
+	TkSizeT offset)			/* Offset into item. */
 {
     int c;
     int flags = PTR2INT(clientData);
@@ -128,7 +128,7 @@ TkStatePrintProc(
     TCL_UNUSED(void *),	/* Ignored. */
     TCL_UNUSED(Tk_Window),		/* Window containing canvas widget. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Offset into item. */
+    TkSizeT offset,			/* Offset into item. */
     TCL_UNUSED(Tcl_FreeProc **))	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
@@ -174,7 +174,7 @@ TkOrientParseProc(
     TCL_UNUSED(Tk_Window),		/* Window containing canvas widget. */
     const char *value,		/* Value of option. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset)			/* Offset into item. */
+	TkSizeT offset)			/* Offset into item. */
 {
     int c;
     size_t length;
@@ -230,7 +230,7 @@ TkOrientPrintProc(
     TCL_UNUSED(void *),	/* Ignored. */
     TCL_UNUSED(Tk_Window),		/* Window containing canvas widget. */
     char *widgRec,		/* Pointer to record for item. */
-    int offset,			/* Offset into item. */
+    TkSizeT offset,			/* Offset into item. */
     TCL_UNUSED(Tcl_FreeProc **))	/* Pointer to variable to fill in with
 				 * information about how to reclaim storage
 				 * for return string. */
@@ -262,7 +262,7 @@ TkOffsetParseProc(
     Tk_Window tkwin,		/* Window on same display as tile */
     const char *value,		/* Name of image */
     char *widgRec,		/* Widget structure record */
-    int offset)			/* Offset of tile in record */
+    TkSizeT offset)			/* Offset of tile in record */
 {
     Tk_TSOffset *offsetPtr = (Tk_TSOffset *) (widgRec + offset);
     Tk_TSOffset tsoffset;
@@ -412,7 +412,7 @@ TkOffsetPrintProc(
     TCL_UNUSED(void *),	/* not used */
     TCL_UNUSED(Tk_Window),		/* not used */
     char *widgRec,		/* Widget structure record */
-    int offset,			/* Offset of tile in record */
+	TkSizeT offset,			/* Offset of tile in record */
     Tcl_FreeProc **freeProcPtr)	/* not used */
 {
     Tk_TSOffset *offsetPtr = (Tk_TSOffset *) (widgRec + offset);
@@ -479,7 +479,7 @@ TkPixelParseProc(
     Tk_Window tkwin,		/* Window on same display as tile */
     const char *value,		/* Name of image */
     char *widgRec,		/* Widget structure record */
-    int offset)			/* Offset of tile in record */
+	TkSizeT offset)			/* Offset of tile in record */
 {
     double *doublePtr = (double *) (widgRec + offset);
     int result;
@@ -513,7 +513,7 @@ TkPixelPrintProc(
     TCL_UNUSED(void *),	/* not used */
     TCL_UNUSED(Tk_Window),		/* not used */
     char *widgRec,		/* Widget structure record */
-    int offset,			/* Offset of tile in record */
+    TkSizeT offset,			/* Offset of tile in record */
     Tcl_FreeProc **freeProcPtr)	/* not used */
 {
     double *doublePtr = (double *) (widgRec + offset);
diff --git a/generic/ttk/ttkEntry.c b/generic/ttk/ttkEntry.c
index fe7f6ff..9e5b63a 100644
--- a/generic/ttk/ttkEntry.c
+++ b/generic/ttk/ttkEntry.c
@@ -84,8 +84,8 @@ typedef struct {
      * Internal state:
      */
     char *string;		/* Storage for string (malloced) */
-    int numBytes;		/* Length of string in bytes. */
-    int numChars;		/* Length of string in characters. */
+    TkSizeT numBytes;		/* Length of string in bytes. */
+    TkSizeT numChars;		/* Length of string in characters. */
 
     int insertPos;		/* Insert index */
     int selectFirst;		/* Index of start of selection, or -1 */
@@ -350,32 +350,32 @@ EntryEditable(Entry *entryPtr)
 /* EntryFetchSelection --
  *	Selection handler for entry widgets.
  */
-static int
+static TkSizeT
 EntryFetchSelection(
-    ClientData clientData, int offset, char *buffer, int maxBytes)
+    ClientData clientData, TkSizeT offset, char *buffer, TkSizeT maxBytes)
 {
     Entry *entryPtr = (Entry *)clientData;
-    int byteCount;
+    TkSizeT byteCount;
     const char *string;
     const char *selStart, *selEnd;
 
-    if (entryPtr->entry.selectFirst < 0 || (!entryPtr->entry.exportSelection)
+    if (entryPtr->entry.selectFirst == -1 || (!entryPtr->entry.exportSelection)
 	    || Tcl_IsSafe(entryPtr->core.interp)) {
-	return -1;
+	return TCL_INDEX_NONE;
     }
     string = entryPtr->entry.displayString;
 
     selStart = Tcl_UtfAtIndex(string, entryPtr->entry.selectFirst);
     selEnd = Tcl_UtfAtIndex(selStart,
 	    entryPtr->entry.selectLast - entryPtr->entry.selectFirst);
+    if (selEnd  <= selStart + offset) {
+	return 0;
+    }
     byteCount = selEnd - selStart - offset;
     if (byteCount > maxBytes) {
     /* @@@POSSIBLE BUG: Can transfer partial UTF-8 sequences.  Is this OK? */
 	byteCount = maxBytes;
     }
-    if (byteCount <= 0) {
-	return 0;
-    }
     memcpy(buffer, selStart + offset, byteCount);
     buffer[byteCount] = '\0';
     return byteCount;
@@ -734,7 +734,7 @@ static void
 EntryStoreValue(Entry *entryPtr, const char *value)
 {
     size_t numBytes = strlen(value);
-    int numChars = Tcl_NumUtfChars(value, numBytes);
+    TkSizeT numChars = Tcl_NumUtfChars(value, numBytes);
 
     if (entryPtr->core.flags & VALIDATING)
 	entryPtr->core.flags |= VALIDATION_SET_VALUE;
@@ -886,7 +886,7 @@ DeleteChars(
     if (index < 0) {
 	index = 0;
     }
-    if (count > entryPtr->entry.numChars - index) {
+    if (count + index > (int)entryPtr->entry.numChars) {
 	count = entryPtr->entry.numChars - index;
     }
     if (count <= 0) {
@@ -1373,8 +1373,8 @@ EntryIndex(
     const char *string;
 
     if (TCL_OK == TkGetIntForIndex(indexObj, entryPtr->entry.numChars - 1, 1, &idx)) {
-    	if (idx + 1 > (TkSizeT)entryPtr->entry.numChars + 1) {
-    	    idx = (TkSizeT)entryPtr->entry.numChars;
+    	if (idx + 1 > entryPtr->entry.numChars + 1) {
+    	    idx = entryPtr->entry.numChars;
     	}
     	*indexPtr = (int)idx;
     	return TCL_OK;
@@ -1389,7 +1389,7 @@ EntryIndex(
     } else if (strncmp(string, "right", length) == 0) {	/* for debugging */
 	*indexPtr = entryPtr->entry.xscroll.last;
     } else if (strncmp(string, "sel.", 4) == 0) {
-	if (entryPtr->entry.selectFirst < 0) {
+	if (entryPtr->entry.selectFirst == -1) {
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		    "selection isn't in widget %s",
 		    Tk_PathName(entryPtr->core.tkwin)));
@@ -1430,7 +1430,7 @@ EntryIndex(
 	 * last character to be selected, for example.
 	 */
 
-	if (roundUp && (*indexPtr < entryPtr->entry.numChars)) {
+	if (roundUp && (*indexPtr < (int)entryPtr->entry.numChars)) {
 	    *indexPtr += 1;
 	}
     } else {
@@ -1463,7 +1463,7 @@ EntryBBoxCommand(
     if (EntryIndex(interp, entryPtr, objv[2], &index) != TCL_OK) {
 	return TCL_ERROR;
     }
-    if ((index == entryPtr->entry.numChars) && (index > 0)) {
+    if ((index == (int)entryPtr->entry.numChars) && (index > 0)) {
 	index--;
     }
     Tk_CharBbox(entryPtr->entry.textLayout, index,
diff --git a/generic/ttk/ttkTagSet.c b/generic/ttk/ttkTagSet.c
index 96e6c4e..33d06bc 100644
--- a/generic/ttk/ttkTagSet.c
+++ b/generic/ttk/ttkTagSet.c
@@ -281,7 +281,7 @@ void Ttk_TagSetValues(Ttk_TagTable tagTable, Ttk_TagSet tagSet, void *record)
 
     for (i = 0; tagTable->optionSpecs[i].type != TK_OPTION_END; ++i) {
 	const Tk_OptionSpec *optionSpec = tagTable->optionSpecs + i;
-	int offset = optionSpec->objOffset;
+	size_t offset = optionSpec->objOffset;
 	int prio = LOWEST_PRIORITY;
 
 	for (j = 0; j < tagSet->nTags; ++j) {
@@ -300,7 +300,7 @@ void Ttk_TagSetApplyStyle(
     const Tk_OptionSpec *optionSpec = tagTable->optionSpecs;
 
     while (optionSpec->type != TK_OPTION_END) {
-	int offset = optionSpec->objOffset;
+	size_t offset = optionSpec->objOffset;
 	const char *optionName = optionSpec->optionName;
 	Tcl_Obj *val = Ttk_StyleMap(style, optionName, state);
 	if (val) {