diff --git a/components/finsh/finsh.h b/components/finsh/finsh.h
index 575066e464050410faf4ba3dd05aaed79eebde6d..12474e841a7427ef382814c898b1e1f4acab14f4 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 c10c3c0092324eb4e48ff8c60eccb6b00909bc57..9a8ef631fd631ff45f6d300303ee831ba3b6a406 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 11f9dc6459d97f5120c1741b20b739f6113b24a5..49d4f8d44ac24202bf571c7ff7041f39ebd8f70c 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 fc1b9acb38f4224fc80b0c267653cf2ef7e23c19..a2e1b5b884b23a821954b59e9efebd0874ff12b3 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 */