diff --git a/.appveyor.yml b/.appveyor.yml
index ba2387cf..adadfdb7 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -1,10 +1,12 @@
-os: Visual Studio 2015
+os:
+  - Visual Studio 2015
+  - Visual Studio 2017
 
 platform:
   - x64
 
 configuration:
-  - Debug
+  #- Debug
   - Release
 
 matrix:
diff --git a/README.md b/README.md
index d06ae11e..48839d43 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@ See [Changes](ChangeLog.md)
 Status:
 -------
 
-Branch / Compiler | clang-3.4,  gcc-4.9, Xcode-7   |  MSVC 2015  | Test Coverage
+Branch / Compiler | clang-3.4,  gcc-4.9, Xcode-7   |  MSVC 2015/2017  | Test Coverage
 ------------------| -------------------------------|-------------|---------------
 master | [![Build Status](https://travis-ci.org/rbock/sqlpp11.svg?branch=master)](https://travis-ci.org/rbock/sqlpp11?branch=master) | [![Build status](https://ci.appveyor.com/api/projects/status/eid7mwqgavo0h61h/branch/master?svg=true)](https://ci.appveyor.com/project/rbock/sqlpp11/branch/master) | [![Coverage Status](https://coveralls.io/repos/rbock/sqlpp11/badge.svg?branch=master)](https://coveralls.io/r/rbock/sqlpp11?branch=master)
 develop | [![Build Status](https://travis-ci.org/rbock/sqlpp11.svg?branch=develop)](https://travis-ci.org/rbock/sqlpp11?branch=develop) | [![Build status](https://ci.appveyor.com/api/projects/status/eid7mwqgavo0h61h/branch/develop?svg=true)](https://ci.appveyor.com/project/rbock/sqlpp11/branch/develop) | [![Coverage Status](https://coveralls.io/repos/rbock/sqlpp11/badge.svg?branch=develop)](https://coveralls.io/r/rbock/sqlpp11?branch=develop)
diff --git a/include/sqlpp11/for_update.h b/include/sqlpp11/for_update.h
index 4d84f9b6..0ee3471a 100644
--- a/include/sqlpp11/for_update.h
+++ b/include/sqlpp11/for_update.h
@@ -162,7 +162,7 @@ namespace sqlpp
     using _serialize_check = serialize_check_of<Context>;
     using T = for_update_data_t;
 
-    static Context& _(const T& t, Context& context)
+    static Context& _(const T&, Context& context)
     {
       context << " FOR UPDATE ";
       return context;
diff --git a/include/sqlpp11/having.h b/include/sqlpp11/having.h
index a5fcfa6c..d2cd2e8b 100644
--- a/include/sqlpp11/having.h
+++ b/include/sqlpp11/having.h
@@ -181,6 +181,12 @@ namespace sqlpp
       static_check_t<not std::is_same<Database, void>::value, assert_having_dynamic_statement_dynamic_t>,
       check_having_t<Expression>>;
 
+  template <typename... Exprs>
+  constexpr auto are_all_parameters_expressions() -> bool
+  {
+    return logic::all_t<is_expression_t<Exprs>::value...>::value;
+  }
+
   // NO HAVING YET
   struct no_having_t
   {
@@ -237,7 +243,7 @@ namespace sqlpp
       //	  template <typename... T>
       //	  using _check = logic::all_t<is_expression_t<T>::value...>;
       template <typename... T>
-      struct _check : logic::all_t<is_expression_t<T>::value...>
+      struct _check : std::integral_constant<bool, are_all_parameters_expressions<T...>()>
       {
       };
 
diff --git a/include/sqlpp11/statement.h b/include/sqlpp11/statement.h
index 34af1dcc..f3fccf49 100644
--- a/include/sqlpp11/statement.h
+++ b/include/sqlpp11/statement.h
@@ -54,6 +54,12 @@ namespace sqlpp
 
   namespace detail
   {
+    template <typename... Policies>
+    constexpr auto is_any_policy_missing() -> bool
+    {
+      return logic::any_t<is_missing_t<Policies>::value...>::value;
+    }
+
     template <typename Db = void, typename... Policies>
     struct statement_policies_t
     {
@@ -122,11 +128,10 @@ namespace sqlpp
       }
 
       using _value_type =
-          typename std::conditional<logic::none_t<is_missing_t<Policies>::value...>::value,
-                                    value_type_of<_result_type_provider>,
-                                    no_value_t  // if a required statement part is missing (e.g. columns in a select),
-                                                // then the statement cannot be used as a value
-                                    >::type;
+          typename std::conditional<is_any_policy_missing<Policies...>(),
+                                    no_value_t,  // if a required statement part is missing (e.g. columns in a select),
+                                                 // then the statement cannot be used as a value
+                                    value_type_of<_result_type_provider>>::type;
 
       using _traits =
           make_traits<_value_type, tag_if<tag::is_expression, not std::is_same<_value_type, no_value_t>::value>>;
diff --git a/test_serializer/ForUpdate.cpp b/test_serializer/ForUpdate.cpp
index 3d57fe43..02bb5c9e 100644
--- a/test_serializer/ForUpdate.cpp
+++ b/test_serializer/ForUpdate.cpp
@@ -31,11 +31,13 @@
 
 namespace
 {
+  /*
   auto getTrue() -> std::string
   {
     MockDb::_serializer_context_t printer = {};
     return serialize(sqlpp::value(true), printer).str();
   }
+  */
 
   auto getFalse() -> std::string
   {
@@ -47,14 +49,14 @@ namespace
 int ForUpdate(int, char* [])
 {
   const auto foo = test::TabFoo{};
-  const auto bar = test::TabBar{};
+  // const auto bar = test::TabBar{};
 
   // Unconditionally
-  compare(__LINE__, select(foo.omega).from(foo).unconditionally().for_update(), "SELECT tab_foo.omega FROM tab_foo FOR UPDATE ");
+  compare(__LINE__, select(foo.omega).from(foo).unconditionally().for_update(),
+          "SELECT tab_foo.omega FROM tab_foo FOR UPDATE ");
 
   // Never
   compare(__LINE__, where(sqlpp::value(false)), " WHERE " + getFalse());
 
-
   return 0;
 }