diff --git a/cores/arduino/IPAddress.cpp b/cores/arduino/IPAddress.cpp
index d9fe5be1d..339002670 100644
--- a/cores/arduino/IPAddress.cpp
+++ b/cores/arduino/IPAddress.cpp
@@ -112,3 +112,4 @@ size_t IPAddress::printTo(Print& p) const
     return n;
 }
 
+const IPAddress INADDR_NONE(0,0,0,0);
\ No newline at end of file
diff --git a/cores/arduino/IPAddress.h b/cores/arduino/IPAddress.h
index d762f2c02..5d0db6e45 100644
--- a/cores/arduino/IPAddress.h
+++ b/cores/arduino/IPAddress.h
@@ -73,6 +73,6 @@ class IPAddress : public Printable {
     friend class DNSClient;
 };
 
-const IPAddress INADDR_NONE(0,0,0,0);
+extern const IPAddress INADDR_NONE;
 
 #endif