diff --git a/components/finsh/finsh.h b/components/finsh/finsh.h
index 575066e464..12474e841a 100644
--- a/components/finsh/finsh.h
+++ b/components/finsh/finsh.h
@@ -24,7 +24,7 @@
 #define FINSH_STRING_MAX        128     /* max length of string */
 #define FINSH_VARIABLE_MAX      8       /* max number of variable */
 
-#define FINSH_STACK_MAX         128     /* max stack size */
+#define FINSH_STACK_MAX         64      /* max stack size */
 #define FINSH_TEXT_MAX          128     /* max text segment size */
 
 #define HEAP_ALIGNMENT          4       /* heap alignment */
diff --git a/components/finsh/finsh_error.c b/components/finsh/finsh_error.c
index c10c3c0092..9a8ef631fd 100644
--- a/components/finsh/finsh_error.c
+++ b/components/finsh/finsh_error.c
@@ -15,7 +15,7 @@
 
 u_char global_errno;
 
-const char* finsh_error_string_table[] =
+static const char* finsh_error_string_table[] =
 {
     "No error",
 	"Invalid token",
diff --git a/components/finsh/finsh_token.c b/components/finsh/finsh_token.c
index 11f9dc6459..49d4f8d44a 100644
--- a/components/finsh/finsh_token.c
+++ b/components/finsh/finsh_token.c
@@ -28,7 +28,7 @@ struct name_table
 };
 
 /* keyword */
-static struct name_table finsh_name_table[] =
+static const struct name_table finsh_name_table[] =
 {
 	{"void",		finsh_token_type_void},
 	{"char",		finsh_token_type_char},
diff --git a/components/finsh/shell.c b/components/finsh/shell.c
index fc1b9acb38..a2e1b5b884 100644
--- a/components/finsh/shell.c
+++ b/components/finsh/shell.c
@@ -144,9 +144,10 @@ void finsh_auto_complete(char* prefix)
 	rt_kprintf("finsh>>%s", prefix);
 }
 
-extern const char* finsh_error_string_table[];
 void finsh_run_line(struct finsh_parser* parser, const char *line)
 {
+	const char* err_str;
+
 	rt_kprintf("\n");
 	finsh_parser_run(parser, (unsigned char*)line);
 
@@ -157,7 +158,8 @@ void finsh_run_line(struct finsh_parser* parser, const char *line)
 	}
 	else
 	{
-		rt_kprintf("%s\n", finsh_error_string(finsh_errno()));
+		err_str = finsh_error_string(finsh_errno());
+		rt_kprintf("%s\n", err_str);
 	}
 
 	/* run virtual machine */