ICE destructuring unsized trait

[jdm]

trait Foo {
    fn send(&self);
}

impl Foo for Box<Foo+Send> {
    fn send(&self) {
        let foo: &Foo+Send = self;
        foo.send()
    }
}

fn main() {
}

godot2:tmp jdm$ rustc trace.rs
error: internal compiler error: trying to take the sizing type of Foo+Send, an unsized type
note: the compiler unexpectedly panicked. 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' panicked at 'Box<Any>', /Users/rustbuild/src/rust-buildbot/slave/nightly-mac/build/src/libsyntax/diagnostic.rs:175

stack backtrace:
   1:        0x10d37b01f - rt::backtrace::imp::write::h8b16685522a2f37e6mt
   2:        0x10d37e1a7 - failure::on_fail::hda0872f4f7b4d652VDt
   3:        0x10d605375 - unwind::begin_unwind_inner::hc18b427b17a69549j1c
   4:        0x10cab0447 - unwind::begin_unwind::h16775218699497008092
   5:        0x10cab0c83 - diagnostic::Handler::bug::he58e2d0573e8d5d4L5F
   6:        0x10a3a1124 - middle::trans::type_of::sizing_type_of::hee62b0bc8796e7a7kic
   7:        0x10a3cd876 - middle::trans::meth::get_vtable::ha051d60ffab0f8ac4rn
   8:        0x10a3ccd80 - middle::trans::expr::apply_adjustments::unsized_info::hbe2033da4ea81f18Sx5
   9:        0x10a3cf0ee - middle::trans::expr::apply_adjustments::unsize_expr::closure.124053
  10:        0x10a3cf33f - middle::trans::expr::apply_adjustments::into_fat_ptr::heb413f79fd24594dcF5
  11:        0x10a3cc356 - middle::trans::expr::apply_adjustments::apply_autoref::hbd93c446aa47d112Pk5
  12:        0x10a3cbc13 - middle::trans::expr::apply_adjustments::apply_autoref::hbd93c446aa47d112Pk5
  13:        0x10a390cbb - middle::trans::expr::trans::h4434d528fe04df5eT84
  14:        0x10a38ec88 - middle::trans::expr::trans_into::h1af41bae8ee0dffbZ44
  15:        0x10a457f1e - middle::trans::_match::store_local::closure.127694
  16:        0x10a457c5f - middle::trans::_match::mk_binding_alloca::h4744195066849425184
  17:        0x10a4285bf - middle::trans::_match::store_local::h0bb5c8564f1380cfN0k
  18:        0x10a38e474 - middle::trans::base::init_local::h05a9a3792652d0c7bCg
  19:        0x10a38d8e1 - middle::trans::controlflow::trans_stmt::h6fdddbb12673cd46yg1
  20:        0x10a38f0e8 - middle::trans::controlflow::trans_block::h6a4e65c7668581e0El1
  21:        0x10a430cf2 - middle::trans::base::trans_closure::hc2af7384d279c318Gwh
  22:        0x10a382b3c - middle::trans::base::trans_fn::hb749e580083af661tIh
  23:        0x10a432b1b - middle::trans::meth::trans_impl::h35da4da3ba6b6e7dhRm
  24:        0x10a3806dd - middle::trans::base::trans_item::h43f06cde27601092H1h
  25:        0x10a4399b9 - middle::trans::base::trans_crate::h3cf75d0bc692f6c9IZi
  26:        0x10a8a82b5 - driver::driver::phase_4_translate_to_llvm::hc964ebcd6d51be4bcoC
  27:        0x10a8a1c92 - driver::driver::compile_input::hbe7ec99668ca396f6UB
  28:        0x10a91e44d - driver::run_compiler::h28311042d2d2d716nLF
  29:        0x10a91c98e - driver::run::closure.146343
  30:        0x10a055feb - task::TaskBuilder<S>::try_future::closure.104775
  31:        0x10a055ee3 - task::TaskBuilder<S>::spawn_internal::closure.104746
  32:        0x10a00f7bd - task::NativeSpawner.Spawner::spawn::closure.2553
  33:        0x10d6639cc - rust_try_inner
  34:        0x10d6639b6 - rust_try
  35:        0x10d602b47 - unwind::try::he8226cb3f62b8c951Pc
  36:        0x10d6029dc - task::Task::run::h4878cb7b665069bf61b
  37:        0x10a00f5e3 - task::NativeSpawner.Spawner::spawn::closure.2477
  38:        0x10d604207 - thread::thread_start::h8e83ad43ae75daab3mc
  39:     0x7fff9a0b1899 - _pthread_body
  40:     0x7fff9a0b172a - _pthread_struct_init

[flaper87]

@nick29581 does the above ring a bell?

[nrc]

Yeah, DST bug, I'll add it to my TODO list

[nrc]

This has been fixed. I'm not exactly sure what by, but there have been a few DST fixes landed recently, they all had tests, so I don't think we need another here.