Index: kernel/generic/src/lib/str.c
===================================================================
--- kernel/generic/src/lib/str.c	(revision 02667d9f8facbf1c4afd9bb4842fefd0a6c1aec9)
+++ kernel/generic/src/lib/str.c	(revision 002fd5f375765c45f5e59bbc374e1418520abddf)
@@ -114,5 +114,5 @@
 
 /** Check the condition if wchar_t is signed */
-#ifdef WCHAR_IS_UNSIGNED
+#ifdef __WCHAR_UNSIGNED__
 	#define WCHAR_SIGNED_CHECK(cond)  (true)
 #else