This is the main remaining thing needed for wow64 thunk. My plan for wow64 thunks is a bit different than other modules. We usually use the same code for 32-bit and 64-bit builds, but have additional code for wow64. However, in winevulkan, we already have two separated code paths for 32-bit and 64-bit implementations and converting arguments is generally more involved than usually. My plan is to use the existing 32-bit thunks as wow64 thunks to avoid having three code paths. The price is that on plain 32-bit builds will do more conversions than strictly necessary, but it doesn't seem too bad.