diff --git a/src/userprog/process.c b/src/userprog/process.c
index a77d9df..accd108 100644
--- a/src/userprog/process.c
+++ b/src/userprog/process.c
@@ -64,7 +64,7 @@ process_execute (const char *cmd)
   return tid;
 }
 
-static bool process_init_stack (char *saveptr, void **esp, char *file_name);
+static bool process_init_stack (char *cmd_saveptr, void **esp, char *file_name);
 static void *push_to_stack (void **esp, void *data, size_t data_size);
 
 /* A thread function that loads a user process and starts it
@@ -125,7 +125,7 @@ start_process (void *cmd)
 /* Helper function that initializes the stack of a newly created 
    user process. Returns true if successful, false otherwise. */
 static bool
-process_init_stack (char *saveptr, void **esp, char *file_name)
+process_init_stack (char *cmd_saveptr, void **esp, char *file_name)
   {
     /* Load command line argument *data* to user process stack.
        This can't cause overflow due to enforcing that the size of
@@ -152,7 +152,7 @@ process_init_stack (char *saveptr, void **esp, char *file_name)
         list_push_front (&arg_list, &arg_elem->elem);
 
         arg_count++;
-        arg = strtok_r (NULL, " ", &saveptr);
+        arg = strtok_r (NULL, " ", &cmd_saveptr);
       }
 
     /* Calculate the remaining number of bytes that need to be written