diff --git a/ext/hal/altera/altera_hal/HAL/src/altera_common.c b/ext/hal/altera/altera_hal/HAL/src/altera_common.c
index f87f3dac28a..58e335ca401 100644
--- a/ext/hal/altera/altera_hal/HAL/src/altera_common.c
+++ b/ext/hal/altera/altera_hal/HAL/src/altera_common.c
@@ -80,3 +80,7 @@ unsigned int alt_busy_sleep (unsigned int us)
 	k_busy_wait(us);
 	return 0;
 }
+
+void alt_printf(const char *fmt, ...)
+{
+}