Fix miri

Author: Nadrieril

src/tools/miri/src/eval.rs

@@ -434,15 +434,10 @@ pub fn eval_entry<'tcx>(
     // Perform the main execution.
     let res: thread::Result<InterpResult<'_, !>> =
         panic::catch_unwind(AssertUnwindSafe(|| ecx.run_threads()));
-    let res = res.unwrap_or_else(|panic_payload| {
+    let Err(res) = res.unwrap_or_else(|panic_payload| {
         ecx.handle_ice();
         panic::resume_unwind(panic_payload)
     });
-    let res = match res {
-        Err(res) => res,
-        // `Ok` can never happen
-        Ok(never) => match never {},
-    };
 
     // Machine cleanup. Only do this if all threads have terminated; threads that are still running
     // might cause Stacked Borrows errors (https://github.com/rust-lang/miri/issues/2396).