diff --git a/Source/Core/Core/Src/HW/EXI_DeviceEthernet.cpp b/Source/Core/Core/Src/HW/EXI_DeviceEthernet.cpp
index a83d755a34..a39173159e 100644
--- a/Source/Core/Core/Src/HW/EXI_DeviceEthernet.cpp
+++ b/Source/Core/Core/Src/HW/EXI_DeviceEthernet.cpp
@@ -19,6 +19,7 @@
 
 #include "EXI_Device.h"
 #include "EXI_DeviceEthernet.h"
+#include <stdarg.h>
 
 //#define SONICDEBUG
 #ifdef SONICDEBUG