vm: cleanups

vm/callstack.cpp

@@ -21,7 +21,7 @@ be calling it at all, so we leave it as it is for now. */
 void *factor_vm::second_from_top_stack_frame(context *ctx)
 {
 	void *frame_top = ctx->callstack_top;
-	for (unsigned i = 0; i < 2; ++i)
+	for (cell i = 0; i < 2; ++i)
 	{
 		void *pred = frame_predecessor(frame_top);
 		if (pred >= ctx->callstack_bottom)

vm/code_heap.cpp

@@ -105,7 +105,6 @@ struct all_blocks_set_verifier {
 	void operator()(code_block *block, cell size)
 	{
 		FACTOR_ASSERT(all_blocks->find((cell)block) != all_blocks->end());
-		// XXX check block size
 	}
 };