diff --git a/libcpu/arm/common/backtrace.c b/libcpu/arm/common/backtrace.c
index 59a4d0bf79e48e61e3e0fa30380252e962cc1631..764c0f5e1b728ac2640a57d6fef7af68f79de5bf 100644
--- a/libcpu/arm/common/backtrace.c
+++ b/libcpu/arm/common/backtrace.c
@@ -42,7 +42,7 @@ void rt_hw_backtrace(rt_uint32_t *fp, rt_uint32_t thread_entry)
 
 	for(i=0; i<10; i++)
 	{
-		fp = *(fp - 3);
+		fp = (rt_uint32_t *)*(fp - 3);
 		pc = *fp ;
 
 		func_entry = pc - 0xC;
diff --git a/libcpu/arm/s3c24x0/cpu.c b/libcpu/arm/s3c24x0/cpu.c
index 34ba6b889b07b8b6a2a7f963a37c3790c6104ed7..a9845f4125dba918c9760839847c268281d044b6 100644
--- a/libcpu/arm/s3c24x0/cpu.c
+++ b/libcpu/arm/s3c24x0/cpu.c
@@ -12,6 +12,7 @@
  * 2006-03-13     Bernard      first version
  */
 
+#include <rthw.h>
 #include <rtthread.h>
 #include "s3c24x0.h"
 
@@ -180,7 +181,10 @@ void rt_hw_cpu_shutdown()
 	rt_kprintf("shutdown...\n");
 
 	level = rt_hw_interrupt_disable();
-	RT_ASSERT(RT_NULL);
+	while (level)
+	{
+		RT_ASSERT(0);
+	}
 }
 
 /*@}*/