{"ast_node_type":"other","tokens":[{"end":56,"kind":"keyword","start":0,"text":"//"}]}
    // FIXME: is it a problem to discard the error here?
    let ecx = mk_eval_cx_to_read_const_val(tcx.tcx, tcx.span, typing_env, CanAccessMutGlobal::No);
    let op = ecx.const_val_to_op(val, ty, None).discard_err()?;