diff --git a/include/errno.h b/include/errno.h
index ccb7869..3af539b 100644
--- a/include/errno.h
+++ b/include/errno.h
@@ -12,12 +12,21 @@
 
 #define __set_errno(val) do { errno = val; } while (0)
 
+/**
+ * errno_str() - get description for error number
+ *
+ * @errno:	error number (negative in case of error)
+ * Return:	string describing the error. If CONFIG_ERRNO_STR is not
+ *		defined an empty string is returned.
+ */
 #ifdef CONFIG_ERRNO_STR
 const char *errno_str(int errno);
 #else
+static const char error_message[] = "";
+
 static inline const char *errno_str(int errno)
 {
-	return 0;
+	return error_message;
 }
 #endif
 #endif /* _ERRNO_H */