From 090d53a74e1ebe256523608c4b7fd90304d611b9 Mon Sep 17 00:00:00 2001
From: Cristian Maglie <c.maglie@bug.st>
Date: Fri, 26 Jul 2013 12:50:17 +0200
Subject: [PATCH] Fixed compile problem for Leonardo after
 0bd6a2d20fb9664255b20e0db11dd4586ebe9007

---
 cores/arduino/USBAPI.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/cores/arduino/USBAPI.h b/cores/arduino/USBAPI.h
index eb2e593..1a4183b 100644
--- a/cores/arduino/USBAPI.h
+++ b/cores/arduino/USBAPI.h
@@ -25,6 +25,8 @@ extern USBDevice_ USBDevice;
 //================================================================================
 //	Serial over CDC (Serial1 is the physical port)
 
+struct ring_buffer;
+
 class Serial_ : public Stream
 {
 private:
@@ -193,4 +195,4 @@ void USB_Flush(uint8_t ep);
 
 #endif
 
-#endif /* if defined(USBCON) */
\ No newline at end of file
+#endif /* if defined(USBCON) */