
'original' tcl8.3.2/generic/tclParse.c, line 1393:
	    code = EvalObjv(interp, objectsUsed, objv, p, bytesLeft, 0);

'new and improved' version:
	    code = EvalObjv(interp, objectsUsed, objv, p, 
			    parse.commandStart + parse.commandSize - p, 0);

comments:
all we've done here is substitute a new and more accurate string length value in lieu of 'bytesLeft'.  parse.commentStart and parse.commentSize could probably also be used to prevent any leading comments from being passed to the tclTrace callback.
