Fix various build warnings (#1473)

Author: DefaultRyan

cppwinrt/component_writers.h

@@ -175,6 +175,9 @@ void* __stdcall %_get_activation_factory([[maybe_unused]] std::wstring_view cons
 int32_t __stdcall WINRT_CanUnloadNow() noexcept
 {
 #ifdef _WRL_MODULE_H_
+#ifdef _MSC_VER
+#pragma warning(suppress: 4324) // structure was padded due to alignment specifier
+#endif
     if (!::Microsoft::WRL::Module<::Microsoft::WRL::InProc>::GetModule().Terminate())
     {
         return 1;

prebuild/prebuild.vcxproj

@@ -120,6 +120,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\cppwinrt</AdditionalIncludeDirectories>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <ControlFlowGuard>Guard</ControlFlowGuard>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
@@ -134,6 +135,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\cppwinrt</AdditionalIncludeDirectories>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <ControlFlowGuard>Guard</ControlFlowGuard>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
@@ -148,6 +150,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\cppwinrt</AdditionalIncludeDirectories>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <ControlFlowGuard>Guard</ControlFlowGuard>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>

strings/base_composable.h

@@ -4,13 +4,20 @@ namespace winrt::impl
     template <typename D>
     struct composable_factory
     {
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4702) // Compiler bug causing spurious "unreachable code" warnings
+#endif
         template <typename I, typename... Args>
         static I CreateInstance(const Windows::Foundation::IInspectable& outer, Windows::Foundation::IInspectable& inner, Args&&... args)
         {
             static_assert(std::is_base_of_v<Windows::Foundation::IInspectable, I>, "Requested interface must derive from winrt::Windows::Foundation::IInspectable");
             inner = CreateInstanceImpl(outer, std::forward<Args>(args)...);
             return inner.as<I>();
         }
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
 
     private:
         template <typename... Args>

strings/base_implements.h

@@ -1390,6 +1390,10 @@ namespace winrt::impl
 
 WINRT_EXPORT namespace winrt
 {
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4702) // Compiler bug causing spurious "unreachable code" warnings
+#endif
     template <typename D, typename... Args>
     auto make(Args&&... args)
     {
@@ -1443,6 +1447,9 @@ WINRT_EXPORT namespace winrt
             return { impl::create_and_initialize<D>(std::forward<Args>(args)...), take_ownership_from_abi };
         }
     }
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
 
     template <typename... FactoryClasses>
     inline void clear_factory_static_lifetime()

test/old_tests/Component/Component.idl

@@ -243,6 +243,8 @@ namespace Component
         HRESULT Create([in] Windows.Foundation.Collections.IVectorView<HSTRING>* _in, [out, retval] FastInputVector** _out);
     };
 
+    midl_pragma warning(disable: 4066) // A member name has been qualified with an interface name because name collisions occurred across interface members on a runtime class.
+
     [version(1.0), activatable(IFastInputVectorFactory, 1.0)]
     runtimeclass FastInputVector
     {
@@ -271,6 +273,8 @@ namespace Component
         interface Windows.Foundation.Collections.IMapView<HSTRING, HSTRING>;
     };
 
+    midl_pragma warning(default: 4066)
+
     //
     // Boxing support for enums and their underlying types.
     //

test/test/fast_iterator.cpp

@@ -48,7 +48,7 @@ TEST_CASE("fast_iterator")
         REQUIRE(2 - (vbegin + 4) > vbegin);
         REQUIRE(vbegin < vbegin + 2);
         REQUIRE(vbegin + 2 - 2 == vbegin);
-        REQUIRE(end(v) - begin(v) == v.Size());
+        REQUIRE(static_cast<uint32_t>(end(v) - begin(v)) == v.Size());
         REQUIRE((begin(v) + 3)[-1] == 4);
     }
     {

test/test_component/OverloadClass.cpp

@@ -8,15 +8,15 @@ namespace winrt::test_component::implementation
     {
         throw hresult_not_implemented();
     }
-    void OverloadClass::Overload(int a)
+    void OverloadClass::Overload(int /*a*/)
     {
         throw hresult_not_implemented();
     }
-    void OverloadClass::Overload(int a, int b)
+    void OverloadClass::Overload(int /*a*/, int /*b*/)
     {
         throw hresult_not_implemented();
     }
-    void OverloadClass::Overload(int a, int b, int c)
+    void OverloadClass::Overload(int /*a*/, int /*b*/, int /*c*/)
     {
         throw hresult_not_implemented();
     }

test/test_component_base/HierarchyB.cpp

@@ -1,6 +1,8 @@
 #include "pch.h"
 #include "HierarchyB.h"
 
+#pragma warning(disable: 4702)
+
 namespace winrt::test_component_base::implementation
 {
     HierarchyB::HierarchyB(hstring const& name)