Add further debug statements on assertion failures
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index d309f6d..4e5b3a6 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -2419,6 +2419,7 @@
     if( ssl->session_negotiate->peer_cert == NULL )
     {
         /* Should never happen */
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
         return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
     }
     peer_pk = &ssl->session_negotiate->peer_cert->pk;
@@ -2772,6 +2773,7 @@
         if( ssl->session_negotiate->peer_cert == NULL )
         {
             /* Should never happen */
+            MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
             return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
         }
         peer_pk = &ssl->session_negotiate->peer_cert->pk;