diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index a8331d9..b4ba88c 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -685,7 +685,7 @@
         return( 0 );
 
     MBEDTLS_SSL_DEBUG_MSG( 3,
-        ( "sending session ticket of length %d", tlen ) );
+        ( "sending session ticket of length %zu", tlen ) );
 
     memcpy( p, ssl->session_negotiate->ticket, tlen );
 
@@ -905,7 +905,7 @@
     *p++ = (unsigned char)( t >>  8 );
     *p++ = (unsigned char)( t       );
 
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, current time: %lu", t ) );
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, current time: %lld", (long long) t ) );
 #else
     if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p, 4 ) ) != 0 )
         return( ret );
@@ -1114,7 +1114,7 @@
     for( i = 0; i < n; i++ )
         *p++ = ssl->session_negotiate->id[i];
 
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, session id len.: %d", n ) );
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, session id len.: %zu", n ) );
     MBEDTLS_SSL_DEBUG_BUF( 3,   "client hello, session id", buf + 39, n );
 
     /*
@@ -1182,7 +1182,7 @@
             continue;
 
         MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, add ciphersuite: %#04x (%s)",
-                                    ciphersuites[i], ciphersuite_info->name ) );
+                                    (unsigned int)ciphersuites[i], ciphersuite_info->name ) );
 
 #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
     defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
@@ -1197,7 +1197,7 @@
     }
 
     MBEDTLS_SSL_DEBUG_MSG( 3,
-        ( "client hello, got %d ciphersuites (excluding SCSVs)", n ) );
+        ( "client hello, got %zu ciphersuites (excluding SCSVs)", n ) );
 
     /*
      * Add TLS_EMPTY_RENEGOTIATION_INFO_SCSV
@@ -1420,7 +1420,7 @@
     /* olen unused if all extensions are disabled */
     ((void) olen);
 
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %d",
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %zu",
                                 ext_len ) );
 
     if( ext_len > 0 )
@@ -2167,10 +2167,10 @@
     }
 
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, current time: %lu",
-                           ( (uint32_t) buf[2] << 24 ) |
-                           ( (uint32_t) buf[3] << 16 ) |
-                           ( (uint32_t) buf[4] <<  8 ) |
-                           ( (uint32_t) buf[5]       ) ) );
+                                     ( (unsigned long) buf[2] << 24 ) |
+                                     ( (unsigned long) buf[3] << 16 ) |
+                                     ( (unsigned long) buf[4] <<  8 ) |
+                                     ( (unsigned long) buf[5]       ) ) );
 
     memcpy( ssl->handshake->randbytes + 32, buf + 2, 32 );
 
@@ -2253,7 +2253,7 @@
     if( ssl->handshake->ciphersuite_info == NULL )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1,
-            ( "ciphersuite info for %04x not found", i ) );
+            ( "ciphersuite info for %04x not found", (unsigned int)i ) );
         mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
                                         MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
         return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
@@ -2261,7 +2261,7 @@
 
     mbedtls_ssl_optimize_checksum( ssl, ssl->handshake->ciphersuite_info );
 
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) );
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %zu", n ) );
     MBEDTLS_SSL_DEBUG_BUF( 3,   "server hello, session id", buf + 35, n );
 
     /*
@@ -2304,7 +2304,7 @@
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "%s session has been resumed",
                    ssl->handshake->resume ? "a" : "no" ) );
 
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %04x", i ) );
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %04x", (unsigned int)i ) );
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d",
                                 buf[37 + n] ) );
 
@@ -2373,7 +2373,7 @@
     ext = buf + 40 + n;
 
     MBEDTLS_SSL_DEBUG_MSG( 2,
-        ( "server hello, total extension length: %d", ext_len ) );
+        ( "server hello, total extension length: %zu", ext_len ) );
 
     while( ext_len )
     {
@@ -2537,7 +2537,7 @@
 
         default:
             MBEDTLS_SSL_DEBUG_MSG( 3,
-                ( "unknown extension found: %d (ignoring)", ext_id ) );
+                ( "unknown extension found: %u (ignoring)", ext_id ) );
         }
 
         ext_len -= 4 + ext_size;
@@ -2628,7 +2628,7 @@
 
     if( ssl->handshake->dhm_ctx.len * 8 < ssl->conf->dhm_min_bitlen )
     {
-        MBEDTLS_SSL_DEBUG_MSG( 1, ( "DHM prime too short: %d < %d",
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "DHM prime too short: %zu < %u",
                                     ssl->handshake->dhm_ctx.len * 8,
                                     ssl->conf->dhm_min_bitlen ) );
         return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
@@ -4347,7 +4347,7 @@
         return( MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET );
     }
 
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket length: %d", ticket_len ) );
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket length: %zu", ticket_len ) );
 
     /* We're not waiting for a NewSessionTicket message any more */
     ssl->handshake->new_session_ticket = 0;