ICE: 'assertion failed: ty::type_is_sized(bcx.tcx(), contents_ty)', /home/laumann/rustlang/src/librustc/middle/trans/expr.rs:1556

[laumann]

enum AnEnum {
    Something(Box<[u8]>)
}

fn main() {
    let buf = [0u8, ..1024];

    let (tx, rx) = channel();
    spawn(proc() {
        tx.send(Something(box *buf.slice(0, 10)));
    });

    let _smth = rx.recv();
}

Compilation backtrace

> RUST_BACKTRACE=1 rustc bug-report.rs                                                                               ~/rust@sneglzilla
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug.
note: we would appreciate a bug report: http://doc.rust-lang.org/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
task 'rustc' failed at 'assertion failed: ty::type_is_sized(bcx.tcx(), contents_ty)', /home/laumann/rustlang/src/librustc/middle/trans/expr.rs:1556

stack backtrace:
   1:     0x7fce2e68b7f0 - rt::backtrace::imp::write::h18da00e3fa21aa27UVq
   2:     0x7fce2e68e980 - failure::on_fail::hf0bf9ceb951d492amhr
   3:     0x7fce32c0e070 - unwind::begin_unwind_inner::h6b7f27e30df90d49SUd
   4:     0x7fce3325f3d0 - unwind::begin_unwind::h11203309285505231177
   5:     0x7fce3364dff0 - middle::trans::expr::trans_uniq_expr::hf654a567423fe43f8T4
   6:     0x7fce3364eb00 - middle::trans::expr::trans_unary::hf911da575068b68f2P4
   7:     0x7fce33643e80 - middle::trans::expr::trans_unadjusted::hccc8ccb9a94a90ec2v3
   8:     0x7fce33607cd0 - middle::trans::expr::trans_into::h6cee4eb39aeb67db4K2
   9:     0x7fce33659160 - middle::trans::expr::trans_adt::hf361baf5d06d970aaH4
  10:     0x7fce3363c5b0 - middle::trans::base::trans_named_tuple_constructor::hef48ebcafb37b2f3Cdf
  11:     0x7fce3360fae0 - middle::trans::callee::trans_call_inner::h6360d135c41f8588V01
  12:     0x7fce336368c0 - middle::trans::callee::trans_call::hbcb2abdb833634a2gV1
  13:     0x7fce336452e0 - middle::trans::expr::trans_rvalue_dps_unadjusted::ha391dd13a949111bd93
  14:     0x7fce33643e80 - middle::trans::expr::trans_unadjusted::hccc8ccb9a94a90ec2v3
  15:     0x7fce336092a0 - middle::trans::expr::trans::heb5629bc9dc8455bYO2
  16:     0x7fce3363cd20 - middle::trans::callee::trans_args::hfb38277828a15ad7Sl2
  17:     0x7fce3360fae0 - middle::trans::callee::trans_call_inner::h6360d135c41f8588V01
  18:     0x7fce33637580 - middle::trans::callee::trans_method_call::h045a13573e018f1coW1
  19:     0x7fce336452e0 - middle::trans::expr::trans_rvalue_dps_unadjusted::ha391dd13a949111bd93
  20:     0x7fce33607cd0 - middle::trans::expr::trans_into::h6cee4eb39aeb67db4K2
  21:     0x7fce336070a0 - middle::trans::controlflow::trans_stmt_semi::hb02369797d17f5e1fRY
  22:     0x7fce33606650 - middle::trans::controlflow::trans_stmt::h5279c34802b7a3172MY
  23:     0x7fce33608160 - middle::trans::controlflow::trans_block::h5bbf02ac441333a58RY
  24:     0x7fce336452e0 - middle::trans::expr::trans_rvalue_dps_unadjusted::ha391dd13a949111bd93
  25:     0x7fce33607cd0 - middle::trans::expr::trans_into::h6cee4eb39aeb67db4K2
  26:     0x7fce33608160 - middle::trans::controlflow::trans_block::h5bbf02ac441333a58RY
  27:     0x7fce336b3b00 - middle::trans::base::trans_closure::h2de5277f401e7e0eSXe
  28:     0x7fce3365a640 - middle::trans::closure::trans_expr_fn::h38a72da08133e093k4i
  29:     0x7fce336452e0 - middle::trans::expr::trans_rvalue_dps_unadjusted::ha391dd13a949111bd93
  30:     0x7fce33643e80 - middle::trans::expr::trans_unadjusted::hccc8ccb9a94a90ec2v3
  31:     0x7fce336092a0 - middle::trans::expr::trans::heb5629bc9dc8455bYO2
  32:     0x7fce3363cd20 - middle::trans::callee::trans_args::hfb38277828a15ad7Sl2
  33:     0x7fce3360fae0 - middle::trans::callee::trans_call_inner::h6360d135c41f8588V01
  34:     0x7fce336368c0 - middle::trans::callee::trans_call::hbcb2abdb833634a2gV1
  35:     0x7fce336452e0 - middle::trans::expr::trans_rvalue_dps_unadjusted::ha391dd13a949111bd93
  36:     0x7fce33607cd0 - middle::trans::expr::trans_into::h6cee4eb39aeb67db4K2
  37:     0x7fce336070a0 - middle::trans::controlflow::trans_stmt_semi::hb02369797d17f5e1fRY
  38:     0x7fce33606650 - middle::trans::controlflow::trans_stmt::h5279c34802b7a3172MY
  39:     0x7fce33608160 - middle::trans::controlflow::trans_block::h5bbf02ac441333a58RY
  40:     0x7fce336b3b00 - middle::trans::base::trans_closure::h2de5277f401e7e0eSXe
  41:     0x7fce335fa1b0 - middle::trans::base::trans_fn::h8818c59c3b560decg9e
  42:     0x7fce335f76c0 - middle::trans::base::trans_item::hbdab4d8b520880d6zsf
  43:     0x7fce336bee00 - middle::trans::base::trans_crate::h8dc93a451eb88c6ePsg
  44:     0x7fce33ab8bf0 - driver::driver::phase_4_translate_to_llvm::hae0d2e943d04f1f7bZw
  45:     0x7fce33ab04c0 - driver::driver::compile_input::hd932c63f3dc5f11b9vw
  46:     0x7fce33b31c80 - driver::run_compiler::ha2ce4a245eb2a747dmA
  47:     0x7fce33b31b60 - driver::main_args::closure.146353
  48:     0x7fce33295bf0 - task::TaskBuilder<S>::try_future::closure.101568
  49:     0x7fce332959e0 - task::TaskBuilder<S>::spawn_internal::closure.101539
  50:     0x7fce32f676d0 - task::spawn_opts::closure.8494
  51:     0x7fce32c6e220 - rust_try_inner
  52:     0x7fce32c6e210 - rust_try
  53:     0x7fce32c0b200 - unwind::try::he73fe587a864f313AJd
  54:     0x7fce32c0b090 - task::Task::run::h3386e28ab4ecfaf2UYc
  55:     0x7fce32f67440 - task::spawn_opts::closure.8434
  56:     0x7fce32c0d110 - thread::thread_start::h86c5236ebccc312cpjd
  57:     0x7fce2da36250 - start_thread
  58:     0x7fce328e43b9 - clone
  59:                0x0 - <unknown>

Version

> rustc --version
rustc 0.12.0-dev (740905042 2014-09-29 23:52:21 +0000)

Seems to be very similar to #16813 and #17118, but the difference is trying to send the value over a channel (removing this gives a "cannot move a value of type [u8]: the size of [u8] cannot be statically determined)

[laumann]

Just to update after the 0.12 release. I tried compiling the above example and am getting the same result (so this issue is still relevant).

> rustc --version=verbose
rustc 0.13.0-dev (86509d8d7 2014-10-12 02:22:14 +0000)
binary: rustc
commit-hash: 86509d8d7ab68c5e4202dea9ff1bfb79409f2f8d
commit-date: 2014-10-12 02:22:14 +0000
host: x86_64-unknown-linux-gnu
release: 0.13.0-dev

[bkoropoff]

Reduced test case:

fn main() {
    (|| { box *([0u].as_slice()) })();
}

Something about the closure lets it get past type checking when it shouldn't.

[bkoropoff]

This looks simple, I'll hopefully have a PR shortly.

[alexcrichton]

Closed by #17984