message: Throw unsupported error when alignment is not a power of two
diff: @@ -60,6 +60,11 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
  this.pointer_size()
  )? as usize;
  + // FIXME: This should actually panic in the interpreted program
  + if !req_align.is_power_of_two() {
  + throw_unsup_format!("Required alignment should always be a power of two")
  + }
  +
  let ptr_scalar = this.read_scalar(ptr_op)?.not_undef()?;
  if let Scalar::Ptr(ptr) = ptr_scalar {
  