- Updated ARMCC_VERSION to __ARMCC_VERSION

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index c77f244..d98eaed 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -44,9 +44,9 @@
 #if defined(_MSC_VER)
 #define inline _inline
 #else
-#if defined(ARMCC_VERSION)
+#if defined(__ARMCC_VERSION)
 #define inline __inline
-#endif /* ARMCC_VERSION */
+#endif /* __ARMCC_VERSION */
 #endif /*_MSC_VER */
 
 /*