diff --git a/hardware/arduino/avr/cores/arduino/Print.h b/hardware/arduino/avr/cores/arduino/Print.h
index 7b53aa4d17e..a2a56de62c6 100644
--- a/hardware/arduino/avr/cores/arduino/Print.h
+++ b/hardware/arduino/avr/cores/arduino/Print.h
@@ -79,6 +79,8 @@ class Print
     size_t println(double, int = 2);
     size_t println(const Printable&);
     size_t println(void);
+
+    virtual void flush() { /* Empty implementation for backward compatibility */ }
 };
 
 #endif
diff --git a/hardware/arduino/avr/cores/arduino/Stream.h b/hardware/arduino/avr/cores/arduino/Stream.h
index 15f6761f001..c30d16463e2 100644
--- a/hardware/arduino/avr/cores/arduino/Stream.h
+++ b/hardware/arduino/avr/cores/arduino/Stream.h
@@ -48,7 +48,6 @@ class Stream : public Print
     virtual int available() = 0;
     virtual int read() = 0;
     virtual int peek() = 0;
-    virtual void flush() = 0;
 
     Stream() {_timeout=1000;}
 
diff --git a/hardware/arduino/sam/cores/arduino/Print.h b/hardware/arduino/sam/cores/arduino/Print.h
index 7b53aa4d17e..a2a56de62c6 100644
--- a/hardware/arduino/sam/cores/arduino/Print.h
+++ b/hardware/arduino/sam/cores/arduino/Print.h
@@ -79,6 +79,8 @@ class Print
     size_t println(double, int = 2);
     size_t println(const Printable&);
     size_t println(void);
+
+    virtual void flush() { /* Empty implementation for backward compatibility */ }
 };
 
 #endif
diff --git a/hardware/arduino/sam/cores/arduino/Stream.h b/hardware/arduino/sam/cores/arduino/Stream.h
index 0d9a49aca3a..b677dd18d52 100644
--- a/hardware/arduino/sam/cores/arduino/Stream.h
+++ b/hardware/arduino/sam/cores/arduino/Stream.h
@@ -48,7 +48,6 @@ class Stream : public Print
     virtual int available() = 0;
     virtual int read() = 0;
     virtual int peek() = 0;
-    virtual void flush() = 0;
 
     Stream() {_timeout=1000;}