fix compiler errors and warning

source/gui/widgets/treebox.cpp

@@ -611,7 +611,7 @@ namespace nana
 						{
 							scroll.create(*data.widget_ptr, nana::rectangle(data.graph->width() - 16, 0, 16, data.graph->height()));
 
-							scroll.events().value_changed.connect_unignorable([this](const arg_scroll& arg)
+							scroll.events().value_changed.connect_unignorable([this](const arg_scroll&)
 							{
 								adjust.scroll_timestamp = nana::system::timestamp();
 								adjust.timer.start();
@@ -1791,7 +1791,6 @@ namespace nana
 					if (!node)
 						return;
 
-					auto & node_state = impl_->node_state;
 					switch (nl.what())
 					{
 					case component::icon:

source/paint/detail/image_ico.hpp

@@ -269,7 +269,9 @@ public:
 	{
 		if (_m_read_ico(data, bytes))
 		{
+#if defined(NANA_WINDOWS)
 			native_handle_ = ::CreateIconFromResourceEx(reinterpret_cast<PBYTE>(const_cast<void*>(data)), static_cast<DWORD>(bytes), TRUE, 0x00030000, 0, 0, LR_DEFAULTCOLOR);
+#endif
 			return true;
 		}
 		return false;