Silence msvc compiler warnings about constant conditional expressions, returning the adress of local variables, and unused formal parameters.

Signed-off-by: Daniela Engert <dani@ngrt.de>

include/boost/variant/detail/multivisitors_cpp11_based.hpp

@@ -25,6 +25,11 @@
 
 #include <tuple>
 
+#ifdef BOOST_MSVC
+#  pragma warning(push)
+#  pragma warning(disable: 4100) // unreferenced formal parameter
+#endif
+
 namespace boost { 
 
 namespace detail { namespace variant {
@@ -179,5 +184,9 @@ namespace detail { namespace variant {
 
 } // namespace boost
 
+#ifdef BOOST_MSVC
+#  pragma warning(pop)
+#endif
+
 #endif // BOOST_VARIANT_DETAIL_MULTIVISITORS_CPP11_BASED_HPP
 

include/boost/variant/get.hpp

@@ -173,6 +173,12 @@ relaxed_get(
 }
 
 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+
+#if defined(BOOST_MSVC)
+# pragma warning(push)
+# pragma warning(disable: 4172) // returning address of local variable or temporary
+#endif
+
 template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
 inline
     U&&
@@ -188,6 +194,11 @@ relaxed_get(
         boost::throw_exception(bad_get());
     return static_cast<U&&>(*result);
 }
+
+#if defined(BOOST_MSVC)
+# pragma warning(pop)
+#endif
+
 #endif
 
 /////////////////////////////////////////////////////////////////////////////////////////////////////////////

include/boost/variant/variant.hpp

@@ -112,6 +112,11 @@
 #endif
 
 
+#if defined(BOOST_MSVC)
+# pragma warning(push)
+# pragma warning(disable: 4127) // conditional expression is constant
+#endif
+
 namespace boost {
 
 namespace detail { namespace variant {
@@ -2484,4 +2489,8 @@ inline void swap(
 #include <boost/variant/detail/variant_io.hpp>
 #endif // BOOST_NO_IOSTREAM
 
+#if defined(BOOST_MSVC)
+# pragma warning(pop)
+#endif
+
 #endif // BOOST_VARIANT_VARIANT_HPP

test/hash_recursive_variant_test.cpp

@@ -36,7 +36,7 @@ using set_t = basic_set_t<value_t>;
 
 struct hash
 {
-    size_t operator()(const value_t& value) const
+    size_t operator()(const value_t&) const
     {
       return 0;
     }

test/variant_get_test.cpp

@@ -9,6 +9,10 @@
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 
+#ifdef _MSC_VER
+#pragma warning(disable: 4127) // conditional expression is constant
+#endif
+
 #include "boost/variant/get.hpp"
 #include "boost/variant/variant.hpp"
 #include "boost/variant/polymorphic_get.hpp"
@@ -362,12 +366,12 @@ public:
     MoveonlyType() {}
     ~MoveonlyType() {}
 
-    MoveonlyType(MoveonlyType&& other) {}
-    void operator=(MoveonlyType&& other) {}
+    MoveonlyType(MoveonlyType&&) {}
+    void operator=(MoveonlyType&&) {}
 
 private:
     MoveonlyType(const MoveonlyType&);
-    void operator=(const MoveonlyType& other);
+    void operator=(const MoveonlyType&);
 };
 
 const boost::variant<int, std::string> foo1() { return ""; }