fix compilation when using stdout protocol

Firmware/communication/communication.cpp

@@ -182,10 +182,10 @@ int _write(int file, const char* data, int len);
 // @brief This is what printf calls internally
 int _write(int file, const char* data, int len) {
 #ifdef USB_PROTOCOL_STDOUT
-    usb_stream_output.process_bytes((const uint8_t *)data, len);
+    usb_stream_output_ptr->process_bytes((const uint8_t *)data, len);
 #endif
 #ifdef UART_PROTOCOL_STDOUT
-    uart4_stream_output.process_bytes((const uint8_t *)data, len);
+    uart4_stream_output_ptr->process_bytes((const uint8_t *)data, len);
 #endif
     return len;
 }

Firmware/communication/interface_uart.cpp

@@ -48,6 +48,7 @@ public:
 private:
     uint8_t tx_buf_[UART_TX_BUFFER_SIZE];
 } uart4_stream_output;
+StreamSink* uart4_stream_output_ptr = &uart4_stream_output;
 
 PacketToStreamConverter uart4_packet_output(uart4_stream_output);
 BidirectionalPacketBasedChannel uart4_channel(uart4_packet_output);

Firmware/communication/interface_uart.h

@@ -2,6 +2,9 @@
 #define __INTERFACE_UART_HPP
 
 #ifdef __cplusplus
+#include "protocol.hpp"
+extern StreamSink* uart4_stream_output_ptr;
+
 extern "C" {
 #endif
 

Firmware/communication/interface_usb.cpp

@@ -67,6 +67,7 @@ public:
 private:
     PacketSink& output_;
 } usb_stream_output(usb_packet_output);
+StreamSink* usb_stream_output_ptr = &usb_stream_output;
 
 #if defined(USB_PROTOCOL_NATIVE)
 BidirectionalPacketBasedChannel usb_channel(usb_packet_output);

Firmware/communication/interface_usb.h

@@ -2,6 +2,9 @@
 #define __INTERFACE_USB_HPP
 
 #ifdef __cplusplus
+#include "protocol.hpp"
+extern StreamSink* usb_stream_output_ptr;
+
 extern "C" {
 #endif