Remove compilaton warnings

diff --git a/lwext4/tree.h b/lwext4/tree.h
index b4db596ed491c920a4d3d26bf4330b4f479f03e7..291ad174cc90b3a5679451e380185157b02b0cab 100644 (file)
--- a/lwext4/tree.h
+++ b/lwext4/tree.h
@@ -31,8 +31,10 @@
 #define        _SYS_TREE_H_
 
 #ifdef __GNUC__
+#ifndef __unused
 #define __unused __attribute__ ((__unused__))
 #endif
+#endif
 /*
  * This file defines data structures for different types of trees:
  * splay trees and red-black trees.