Tcl Source Code

2011-08-16  Don Porter  <[email protected]>

	* generic/tclCompile.c: [Bug 3392070] More complete prevention of
	Tcl_Obj reference cycles when producing an intrep of ByteCode.

2011-08-16  Donal K. Fellows  <[email protected]>

	* generic/tclListObj.c (TclLindexList, TclLsetFlat): Silence warnings
	about (unreachable) cases of uninitialized variables.
	* generic/tclCmdIL.c (SelectObjFromSublist): Improve the generation of
	* generic/tclIndexObj.c (Tcl_ParseArgsObjv): messages through the use
	* generic/tclVar.c (ArrayStartSearchCmd):    of Tcl_ObjPrintf.

    for (i = 0;  i < numLitObjects;  i++) {
	if (objPtr == envPtr->literalArrayPtr[i].objPtr) {
	    /*
	     * Prevent circular reference where the bytecode intrep of
	     * a value contains a literal which is that same value.
	     * If this is allowed to happen, refcount decrements may not
	     * reach zero, and memory may leak.  Bugs 467523, 3357771
	     *
	     * NOTE:  [Bugs 3392070, 3389764] We make a copy based completely
	     * on the string value, and do not call Tcl_DuplicateObj() so we
             * can be sure we do not have any lingering cycles hiding in
	     * the intrep.
	     */
	    int numBytes;
	    const char *bytes = Tcl_GetStringFromObj(objPtr, &numBytes);

	    codePtr->objArrayPtr[i] = Tcl_DuplicateObj(objPtr);
	    codePtr->objArrayPtr[i] = Tcl_NewStringObj(bytes, numBytes);
	    Tcl_IncrRefCount(codePtr->objArrayPtr[i]);
	    Tcl_DecrRefCount(objPtr);
	} else {
	    codePtr->objArrayPtr[i] = envPtr->literalArrayPtr[i].objPtr;
	}
    }