Issue 1:
rustc is not checking that all types that are put into a sized-context are in fact sized.

Consider for example:

pub enum BsonValue {
A([u8]),
B([BsonValue]),
}

pub fn set_value(_v:&BsonValue)
{
}

fn main()
{
}

This yields an ICE:

thread 'rustc' panicked at 'Unexpected type returned from struct_tail: BsonValue for ty=BsonValue', /home/rustbuild/src/rust-buildbot/slave/beta-dist-rustc-linux/build/src/librustc_trans/trans/type_of.rs:366

Original bug report follows

erics-air-2:Elmo eric$ rustc --version
rustc 1.0.0-beta.3 (5241bf9c3 2015-04-25) (built 2015-04-25)

I'm on MacOS X Mavericks.

Here's the source file that causes the problem (I'm a rust newbie):

enum BsonValue {
BDouble(f64),
BString(String),
BInt64(i64),
BInt32(i32),
BUndefined,
BObjectID([u8]),
BNull,
BRegex(String,String),
BJSCode(String),
BJSCodeWithScope(String),
BBinary(u8,[u8]),
BMinKey,
BMaxKey,
BDateTime(i64),
BTimeStamp(i64),
BBoolean(bool),
BArray([BsonValue]),
BDocument([(String,BsonValue)]),
}

fn setValueForKey (doc:&BsonValue, k:String, v:&BsonValue)
{
}

fn main()
{
}

And here's the output of the compiler:

erics-air-2:Elmo eric$ RUST_BACKTRACE=1 rustc b.rs
b.rs:2:1: 21:2 warning: enum is never used: `BsonValue`, #[warn(dead_code)] on by default
b.rs:2 enum BsonValue {
b.rs:3 BDouble(f64),
b.rs:4 BString(String),
b.rs:5 BInt64(i64),
b.rs:6 BInt32(i32),
b.rs:7 BUndefined,
...
b.rs:23:1: 25:2 warning: function is never used: `setValueForKey`, #[warn(dead_code)] on by default
b.rs:23 fn setValueForKey (doc:&BsonValue, k:String, v:&BsonValue)
b.rs:24 {
b.rs:25 }
b.rs:23:20: 23:23 warning: unused variable: `doc`, #[warn(unused_variables)] on by default
b.rs:23 fn setValueForKey (doc:&BsonValue, k:String, v:&BsonValue)
^~~
b.rs:23:36: 23:37 warning: unused variable: `k`, #[warn(unused_variables)] on by default
b.rs:23 fn setValueForKey (doc:&BsonValue, k:String, v:&BsonValue)
^
b.rs:23:46: 23:47 warning: unused variable: `v`, #[warn(unused_variables)] on by default
b.rs:23 fn setValueForKey (doc:&BsonValue, k:String, v:&BsonValue)
^
b.rs:23:1: 25:2 warning: function `setValueForKey` should have a snake case name such as `set_value_for_key`, #[warn(non_snake_case)] on by default
b.rs:23 fn setValueForKey (doc:&BsonValue, k:String, v:&BsonValue)
b.rs:24 {
b.rs:25 }
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
note: run with `RUST_BACKTRACE=1` for a backtrace
thread 'rustc' panicked at 'Unexpected type returned from struct_tail: BsonValue for ty=BsonValue', /Users/rustbuild/src/rust-buildbot/slave/beta-dist-rustc-mac/build/src/librustc_trans/trans/type_of.rs:366

stack backtrace:
1: 0x1085cc33f - sys::backtrace::write::h0f2fc53eb11eb814gWr
2: 0x1085d4942 - panicking::on_panic::hd617a4042e8486fciUv
3: 0x108591375 - rt::unwind::begin_unwind_inner::hd84dfec22ac3667d1Bv
4: 0x108592206 - rt::unwind::begin_unwind_fmt::h5bb6fa95bd57b24bFAv
5: 0x10566046f - trans::type_of::in_memory_type_of::hb4e9c324c5b50f3epkL
6: 0x105732682 - trans::type_of::type_of_rust_fn::h693a4c7fdf6ff62b87K
7: 0x10566e00c - trans::declare::declare_rust_fn::hb0911ef870c7fe86SJz
8: 0x10569462f - trans::base::register_fn::ha9cdc6c185aa084bVmi
9: 0x10568f2d1 - trans::base::get_item_val::hfda21a63917f43e1Dzi
10: 0x10568b3c7 - trans::base::trans_item::h2033cab24c2319dbFbi
11: 0x10569a220 - trans::base::trans_crate::h3375b1d0f4de8d89F0i
12: 0x10511ed4e - driver::phase_4_translate_to_llvm::hc94112f0d91aac3chOa
13: 0x1050f72a4 - driver::compile_input::h4747d8bb1c595fdfQba
14: 0x1051be8f3 - run_compiler::hc8c95c5858347fdbz4b
15: 0x1051bc41a - boxed::F.FnBox<A>::call_box::h7872786064439979928
16: 0x1051bb8b7 - rt::unwind::try::try_fn::h10239991317224243769
17: 0x1086557c8 - rust_try_inner
18: 0x1086557b5 - rust_try
19: 0x1051bbb90 - boxed::F.FnBox<A>::call_box::h4543691575426869824
20: 0x1085d348d - sys::thread::create::thread_start::h499b3be451a7bbb8AZu
21: 0x7fff8aca1898 - _pthread_body
22: 0x7fff8aca1729 - _pthread_start

Issue 2:
enum Foo {
Bar(int, [int]),
}

fn main() {
// Either of these lines can cause the ICE
let _x: &(int, [int]);
let _y: &Foo;
}

Backtrace:

1: 0x7f2a127e8580 - rt::backtrace::imp::write::h0180e7ded76a3ff2c0q
2: 0x7f2a127eb770 - failure::on_fail::h3f169393c89b5f90Tlr
3: 0x7f2a12fd24f0 - unwind::begin_unwind_inner::haeb9517b5061bc86Zie
4: 0x7f2a133ad670 - unwind::begin_unwind::h17017358962417336117
5: 0x7f2a13803a20 - middle::ty::unsized_part_of_type::h8eae6d239e9b7af3tnG
6: 0x7f2a138037c0 - middle::trans::type_of::type_of::type_of_unsize_info::h67819f63aa2acfb5Xh9
7: 0x7f2a1377b050 - middle::trans::type_of::type_of::h3c89a1738d384c45Ih9
8: 0x7f2a1377b050 - middle::trans::type_of::type_of::h3c89a1738d384c45Ih9
9: 0x7f2a137b0860 - middle::trans::base::alloc_ty::h5485998eeb61d023mTd
10: 0x7f2a13859870 - middle::trans::_match::mk_binding_alloca::h11628361498234501597
11: 0x7f2a1385bdf0 - middle::trans::_match::store_local::create_dummy_locals::closure.119283
12: 0x7f2a13681560 - middle::pat_util::pat_bindings::closure.112016
13: 0x7f2a0ea1ccb0 - ast_util::walk_pat::hc858153057fb5965oRB
14: 0x7f2a138205f0 - middle::trans::_match::store_local::h9195017fe21b4124A2h
15: 0x7f2a13772d10 - middle::trans::base::init_local::h5e8a493dc2ae05b1WFd
16: 0x7f2a13772220 - middle::trans::controlflow::trans_stmt::hf26d5cee55a6056blhY
17: 0x7f2a13773c40 - middle::trans::controlflow::trans_block::h004dea36138a75c8wmY
18: 0x7f2a13829560 - middle::trans::base::trans_closure::h655acfc433ac13fevye
19: 0x7f2a13764670 - middle::trans::base::trans_fn::hf0a444fa9ff43aebiKe
20: 0x7f2a1375f9b0 - middle::trans::base::trans_item::hda4d4160cb2b58dfi2e
21: 0x7f2a138341f0 - middle::trans::base::trans_crate::hff0f87c98e6356c8JWf
22: 0x7f2a13c058d0 - driver::driver::phase_4_translate_to_llvm::h8223ee9d7ab4951cpzy
23: 0x7f2a13bfd280 - driver::driver::compile_input::hfa4fd95c9e6a2ceeQby
24: 0x7f2a13c8f0a0 - driver::run_compiler::h32bdccca6ed9465cJIB
25: 0x7f2a13c8efb0 - driver::main_args::closure.138206
26: 0x7f2a13ca1240 - task::TaskBuilder<S>::try_future::closure.139324
27: 0x7f2a13ca1040 - task::TaskBuilder<S>::spawn_internal::closure.139301
28: 0x7f2a146dcf10 - task::spawn_opts::closure.8369
29: 0x7f2a1302af90 - rust_try_inner
30: 0x7f2a1302af80 - rust_try
31: 0x7f2a12fcfb20 - unwind::try::h03d8d1d4cb0de0c1f7d
32: 0x7f2a12fcf8e0 - task::Task::run::hafab6bcab45e61e5zdd
33: 0x7f2a146dcc70 - task::spawn_opts::closure.8315
34: 0x7f2a12fd16e0 - thread::thread_start::hba588af1f803bb5blCd
35: 0x7f2a1227f0c0 - start_thread
36: 0x7f2a12c99359 - __clone
37: 0x0 - <unknown>

This seems to occur when using a non-struct type that contains an unsized type. This is probably because unsized_part_of_type only handles ty_struct and the base unsized types. This should be extended to handle enums and tuples as well.