message: Shim intrinsics::atomic_singlethreadfence, etc.
diff: @@ -113,6 +113,10 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
  | "atomic_fence_rel"
  | "atomic_fence_acqrel"
  | "atomic_fence"
  + | "atomic_singlethreadfence_acq"
  + | "atomic_singlethreadfence_rel"
  + | "atomic_singlethreadfence_acqrel"
  + | "atomic_singlethreadfence"
  => {
  // we are inherently singlethreaded and singlecored, this is a nop
  }
  