diff --git a/include/iotrace.h b/include/iotrace.h
index 9bd1f16..e4ceb61 100644
--- a/include/iotrace.h
+++ b/include/iotrace.h
@@ -31,10 +31,11 @@
 #define writew(val, addr)	iotrace_writew(val, (const void *)(addr))
 
 #undef readb
-#define readb(addr)	iotrace_readb((const void *)(addr))
+#define readb(addr)	iotrace_readb((const void *)(uintptr_t)addr)
 
 #undef writeb
-#define writeb(val, addr)	iotrace_writeb(val, (const void *)(addr))
+#define writeb(val, addr) \
+	iotrace_writeb(val, (const void *)(uintptr_t)addr)
 
 #endif