diff --git a/lib/clib/memcpy.c b/lib/clib/memcpy.c
index 500979fb..154a5074 100644
--- a/lib/clib/memcpy.c
+++ b/lib/clib/memcpy.c
@@ -32,7 +32,7 @@
 
 #include "clib.h"
 
-#ifdef __GNUC__
+#if defined(__GNUC__)  && !defined(AOS3)
 #pragma GCC diagnostic ignored "-Wcast-align"
 #endif
 
diff --git a/lib/clib/memset.c b/lib/clib/memset.c
index a7ceca62..0ec1ecc2 100644
--- a/lib/clib/memset.c
+++ b/lib/clib/memset.c
@@ -35,7 +35,7 @@
 
 #include "clib.h"
 
-#ifdef __GNUC__
+#if defined(__GNUC__)  && !defined(AOS3)
 #pragma GCC diagnostic ignored "-Wcast-align"
 #endif
 
diff --git a/lib/platform.h b/lib/platform.h
index f72f0960..08d477a6 100644
--- a/lib/platform.h
+++ b/lib/platform.h
@@ -66,13 +66,13 @@
 #endif
 
 // Check weather an POSIX compatible API is available
-#if defined(unix) || defined(__unix__) || defined(__unix)
+#if defined(unix) || defined(__unix__) || defined(__unix)
 # ifndef UNIX
-#  define UNIX
-# endif
+#  define UNIX
+# endif
 # include <unistd.h>
-# include <dirent.h>
-# include <termios.h>
+# include <dirent.h>
+# include <termios.h>
 #endif
 
 /* STDC */
@@ -83,7 +83,7 @@
 #endif
 
 /* GCC 2.95 */
-#if (_GNUC_ == 2 && __GNUC_MINOR__ == 95)
+#if (__GNUC__ == 2 && __GNUC_MINOR__ == 95)
 # include <sys/types.h>
 typedef u_int8_t    uint8_t;
 typedef u_int16_t   uint16_t;