diff --git a/src/internal.c b/src/internal.c
index 6a4357544..a7b557dcc 100644
--- a/src/internal.c
+++ b/src/internal.c
@@ -3818,7 +3818,6 @@ static INLINE int Encrypt(CYASSL* ssl, byte* out, const byte* input, word16 sz)
         #ifdef BUILD_AES
             case cyassl_aes:
                 return AesCbcEncrypt(ssl->encrypt.aes, out, input, sz);
-                break;
         #endif
 
         #ifdef BUILD_AESGCM
@@ -3914,7 +3913,6 @@ static INLINE int Encrypt(CYASSL* ssl, byte* out, const byte* input, word16 sz)
         #ifdef HAVE_HC128
             case cyassl_hc128:
                 return Hc128_Process(ssl->encrypt.hc128, out, input, sz);
-                break;
         #endif
 
         #ifdef BUILD_RABBIT
@@ -3969,7 +3967,6 @@ static INLINE int Decrypt(CYASSL* ssl, byte* plain, const byte* input,
         #ifdef BUILD_AES
             case cyassl_aes:
                 return AesCbcDecrypt(ssl->decrypt.aes, plain, input, sz);
-                break;
         #endif
 
         #ifdef BUILD_AESGCM
@@ -4053,7 +4050,6 @@ static INLINE int Decrypt(CYASSL* ssl, byte* plain, const byte* input,
         #ifdef HAVE_HC128
             case cyassl_hc128:
                 return Hc128_Process(ssl->decrypt.hc128, plain, input, sz);
-                break;
         #endif
 
         #ifdef BUILD_RABBIT
@@ -8316,22 +8312,16 @@ static void PickHashSigAlgo(CYASSL* ssl,
         switch(size) {
             case 20:
                 return secp160r1;
-                break;
             case 24:
                 return secp192r1;
-                break;
             case 28:
                 return secp224r1;
-                break;
             case 32:
                 return secp256r1;
-                break;
             case 48:
                 return secp384r1;
-                break;
             case 66:
                 return secp521r1;
-                break;
             default:
                 return 0;
         }        
diff --git a/src/io.c b/src/io.c
index 1b47a8340..c1daaf70e 100644
--- a/src/io.c
+++ b/src/io.c
@@ -56,7 +56,13 @@
         #include <posix.h>
         #include <rtcs.h>
     #elif defined(CYASSL_MDK_ARM)
+        #if defined(CYASSL_MDK5)
+            #include "cmsis_os.h"
+            #include "rl_fs.h" 
+            #include "rl_net.h" 
+        #else
         #include <rtl.h>
+        #endif
         #undef RNG
         #include "CYASSL_MDK_ARM.h"
         #undef RNG
@@ -126,13 +132,23 @@
     #define SOCKET_ECONNREFUSED RTCSERR_TCP_CONN_REFUSED
     #define SOCKET_ECONNABORTED RTCSERR_TCP_CONN_ABORTED
 #elif defined(CYASSL_MDK_ARM)
-    #define SOCKET_EWOULDBLOCK SCK_EWOULDBLOCK
-    #define SOCKET_EAGAIN      SCK_ELOCKED
-    #define SOCKET_ECONNRESET  SCK_ECLOSED
-    #define SOCKET_EINTR       SCK_ERROR
-    #define SOCKET_EPIPE       SCK_ERROR
-    #define SOCKET_ECONNREFUSED SCK_ERROR
-    #define SOCKET_ECONNABORTED SCK_ERROR
+    #if defined(CYASSL_MDK5)
+        #define SOCKET_EWOULDBLOCK BSD_ERROR_WOULDBLOCK
+        #define SOCKET_EAGAIN      BSD_ERROR_LOCKED
+        #define SOCKET_ECONNRESET  BSD_ERROR_CLOSED
+        #define SOCKET_EINTR       BSD_ERROR
+        #define SOCKET_EPIPE       BSD_ERROR
+        #define SOCKET_ECONNREFUSED BSD_ERROR
+        #define SOCKET_ECONNABORTED BSD_ERROR
+    #else
+        #define SOCKET_EWOULDBLOCK SCK_EWOULDBLOCK
+        #define SOCKET_EAGAIN      SCK_ELOCKED
+        #define SOCKET_ECONNRESET  SCK_ECLOSED
+        #define SOCKET_EINTR       SCK_ERROR
+        #define SOCKET_EPIPE       SCK_ERROR
+        #define SOCKET_ECONNREFUSED SCK_ERROR
+        #define SOCKET_ECONNABORTED SCK_ERROR
+    #endif
 #else
     #define SOCKET_EWOULDBLOCK EWOULDBLOCK
     #define SOCKET_EAGAIN      EAGAIN
diff --git a/src/ssl.c b/src/ssl.c
index 3397c9f2c..3a6ab83e2 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -89,12 +89,12 @@
 #endif /* min */
 
 #ifndef max
-
+#ifdef CYASSL_DTLS
     static INLINE word32 max(word32 a, word32 b)
     {
         return a > b ? a : b;
     }
-
+#endif
 #endif /* min */
 
 
@@ -2095,7 +2095,12 @@ int CyaSSL_CertManagerVerifyBuffer(CYASSL_CERT_MANAGER* cm, const byte* buff,
 #else
     /* stdio, default case */
     #define XFILE      FILE*
-    #define XFOPEN     fopen 
+    #if defined(CYASSL_MDK_ARM)
+        extern FILE * CyaSSL_fopen(const char *name, const char *mode) ;
+        #define XFOPEN     CyaSSL_fopen
+    #else
+        #define XFOPEN     fopen
+    #endif
     #define XFSEEK     fseek
     #define XFTELL     ftell
     #define XREWIND    rewind
@@ -5756,6 +5761,7 @@ int CyaSSL_set_compression(CYASSL* ssl)
     #define CloseSocket(s) closesocket(s)
 #elif defined(CYASSL_MDK_ARM)
     #define CloseSocket(s) closesocket(s)
+    extern int closesocket(int) ;
 #else
     #define CloseSocket(s) close(s)
 #endif
@@ -9889,7 +9895,6 @@ static int initGlobalRNG = 0;
                 case ARC4_TYPE:
                     CYASSL_MSG("returning arc4 state");
                     return (void*)&ctx->cipher.arc4.x;
-                    break;
 
                 default:
                     CYASSL_MSG("bad x state type");
@@ -9910,7 +9915,6 @@ static int initGlobalRNG = 0;
                 case ARC4_TYPE:
                     CYASSL_MSG("returning arc4 state size");
                     return sizeof(Arc4);
-                    break;
 
                 default:
                     CYASSL_MSG("bad x state type");
@@ -10013,7 +10017,6 @@ static int initGlobalRNG = 0;
             case AES_256_CBC_TYPE :
                 CYASSL_MSG("AES CBC");
                 return AES_BLOCK_SIZE;
-                break;
 
 #ifdef CYASSL_AES_COUNTER
             case AES_128_CTR_TYPE :
@@ -10021,28 +10024,23 @@ static int initGlobalRNG = 0;
             case AES_256_CTR_TYPE :
                 CYASSL_MSG("AES CTR");
                 return AES_BLOCK_SIZE;
-                break;
 #endif
 
             case DES_CBC_TYPE :
                 CYASSL_MSG("DES CBC");
                 return DES_BLOCK_SIZE;
-                break;
                 
             case DES_EDE3_CBC_TYPE :
                 CYASSL_MSG("DES EDE3 CBC");
                 return DES_BLOCK_SIZE;
-                break;
 
             case ARC4_TYPE :
                 CYASSL_MSG("ARC4");
                 return 0;
-                break;
 
             case NULL_CIPHER_TYPE :
                 CYASSL_MSG("NULL");
                 return 0;
-                break;
 
             default: {
                 CYASSL_MSG("bad type");