update build to support mshv3 feature

Signed-off-by: Simon Davies <[email protected]>

Author: simongdavies

src/hyperlight_host/build.rs

@@ -85,19 +85,24 @@ fn main() -> Result<()> {
     }
 
     // Makes #[cfg(kvm)] == #[cfg(all(feature = "kvm", target_os = "linux"))]
-    // and #[cfg(mshv)] == #[cfg(all(feature = "mshv", target_os = "linux"))].
+    // and #[cfg(mshv)] == #[cfg(all(any(feature = "mshv2", feature = "mshv3"), target_os = "linux"))].
     // Essentially the kvm and mshv features are ignored on windows as long as you use #[cfg(kvm)] and not #[cfg(feature = "kvm")].
     // You should never use #[cfg(feature = "kvm")] or #[cfg(feature = "mshv")] in the codebase.
     cfg_aliases::cfg_aliases! {
         kvm: { all(feature = "kvm", target_os = "linux") },
-        mshv: { all(feature = "mshv", target_os = "linux") },
+        mshv: { all(any(feature = "mshv2", feature = "mshv3"), target_os = "linux") },
         // inprocess feature is aliased with debug_assertions to make it only available in debug-builds.
         // You should never use #[cfg(feature = "inprocess")] in the codebase. Use #[cfg(inprocess)] instead.
         inprocess: { all(feature = "inprocess", debug_assertions) },
         // crashdump feature is aliased with debug_assertions to make it only available in debug-builds.
         crashdump: { all(feature = "crashdump", debug_assertions) },
         // print_debug feature is aliased with debug_assertions to make it only available in debug-builds.
         print_debug: { all(feature = "print_debug", debug_assertions) },
+        // the following features are mutually exclusive but rather than enforcing that here we are enabling mshv3 to override mshv2 when both are enabled
+        // because mshv2 is in the default feature set we want to allow users to enable mshv3 without having to set --no-default-features and the re-enable
+        // the other features they want.
+        mshv2: { all(feature = "mshv2", not(feature="mshv3"), target_os = "linux") },
+        mshv3: { all(feature = "mshv3", target_os = "linux") },
     }
 
     write_built_file()?;