diff --git a/src/kservice.c b/src/kservice.c
index 5a59345b3e6..167f94a6a72 100644
--- a/src/kservice.c
+++ b/src/kservice.c
@@ -448,7 +448,7 @@ rt_weak rt_err_t rt_backtrace_formatted_print(rt_ubase_t *buffer, long buflen)
 {
     rt_kprintf("please use: addr2line -e rtthread.elf -a -f");
 
-    for (size_t i = 0; i < buflen && buffer[i] != 0; i++)
+    for (rt_size_t i = 0; i < buflen && buffer[i] != 0; i++)
     {
         rt_kprintf(" 0x%lx", (rt_ubase_t)buffer[i]);
     }
diff --git a/src/thread.c b/src/thread.c
index d9816b52776..994e04d6f5e 100644
--- a/src/thread.c
+++ b/src/thread.c
@@ -829,7 +829,7 @@ rt_err_t rt_thread_control(rt_thread_t thread, int cmd, void *arg)
         {
             rt_uint8_t cpu;
 
-            cpu = (rt_uint8_t)(size_t)arg;
+            cpu = (rt_uint8_t)(rt_size_t)arg;
             return rt_sched_thread_bind_cpu(thread, cpu);
         }