Index: arch/mips32/src/drivers/serial.c
===================================================================
--- arch/mips32/src/drivers/serial.c	(revision 80d2bdbb59aff7f143abc484128e57a0c2b47e47)
+++ arch/mips32/src/drivers/serial.c	(revision 631ca4d04a2284ebd54da4b84fc569fab1e212a4)
@@ -113,8 +113,8 @@
 iroutine old_timer;
 /** Do polling on timer interrupt */
-static void timer_replace(int n, void *stack)
+static void timer_replace(int n, istate_t *istate)
 {
-	old_timer(n, stack);
-	serial_interrupt(n, stack);
+	old_timer(n, istate);
+	serial_interrupt(n, istate);
 }