linux: Tweak wl device setup when building without gpu

I was skimming the gpu flag code (tpm will need something similar) and
found the way resource_bridge_wl_socket is used misleading. The same
variable is declared in two different places depending on whether
building with gpu. This CL combines them into one `let` statement.

Also moved the generic param onto None which comes out more readable
after rustfmt while still providing helpful context for the reader.

TEST=cargo check && cargo check --features gpu

Change-Id: I57a1ae214947475efa7bf01ab123a71a58411244
Reviewed-on: https://chromium-review.googlesource.com/1470915
Commit-Ready: David Tolnay <dtolnay@chromium.org>
Tested-by: David Tolnay <dtolnay@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Zach Reizner <zachr@chromium.org>

1 files changed, 4 insertions, 7 deletions

diff --git a/src/linux.rs b/src/linux.rs
index 1dbd8fd..762b882 100644
--- a/src/linux.rs
+++ b/src/linux.rs
@@ -488,10 +488,10 @@ fn create_virtio_devs(
         }
     }
 
-    #[cfg(feature = "gpu")]
-    let mut resource_bridge_wl_socket: Option<
-        devices::virtio::resource_bridge::ResourceRequestSocket,
-    > = None;
+    #[cfg_attr(not(feature = "gpu"), allow(unused_mut))]
+    let mut resource_bridge_wl_socket =
+        None::<devices::virtio::resource_bridge::ResourceRequestSocket>;
+
     #[cfg(feature = "gpu")]
     {
         if cfg.gpu {
@@ -591,9 +591,6 @@ fn create_virtio_devs(
         let jailed_wayland_dir = Path::new("/wayland");
         let jailed_wayland_path = jailed_wayland_dir.join(wayland_socket_name);
 
-        #[cfg(not(feature = "gpu"))]
-        let resource_bridge_wl_socket = None;
-
         let wl_box = Box::new(
             devices::virtio::Wl::new(
                 if cfg.multiprocess {