diff --git a/include/asm-v850/hardirq.h b/include/asm-v850/hardirq.h
index 4f913bc..d98488c 100644
--- a/include/asm-v850/hardirq.h
+++ b/include/asm-v850/hardirq.h
@@ -24,4 +24,6 @@
 # error HARDIRQ_BITS is too low!
 #endif
 
+void ack_bad_irq(unsigned int irq);
+
 #endif /* __V850_HARDIRQ_H__ */