Issue 1:
For this source code I get an internal compiler error. I don't have a debug version of Rust so the stack backtrace is only mildly useful. I am using thestinger's 64bit Arch package at commit 776c17f. If necessary, I can compile a debug version.

use std::mem::{transmute, size_of};

pub fn as_raw_bytes<'a, T>(obj: &'a T) -> &'a [u8] {
unsafe {
transmute(Slice{
data: transmute(obj),
len: size_of::<T>()
})
}
}

stack backtrace:
1: 0x7f1dd6635d10 - rt::backtrace::imp::write::h4e2a0deea6e16f19lxr
2: 0x7f1dd6638de0 - <unknown>
3: 0x7f1ddabdb420 - unwind::begin_unwind_inner::ha1744a0e31e40fb7pie
4: 0x7f1dd7fda200 - <unknown>
5: 0x7f1dd7fd9230 - reader::get_doc::hd591db736e2c9ccanSa
6: 0x7f1ddbab23e0 - metadata::decoder::get_type::hf1b9e21cbe87e9e4zyu
7: 0x7f1ddb4f13b0 - middle::ty::lookup_item_type::had5e7ab5a7be10d4pNI
8: 0x7f1ddb84de60 - <unknown>
9: 0x7f1ddb84b7c0 - <unknown>
10: 0x7f1ddb84de60 - <unknown>
11: 0x7f1ddb817d10 - <unknown>
12: 0x7f1ddb84de60 - <unknown>
13: 0x7f1ddb817d10 - <unknown>
14: 0x7f1ddb813aa0 - <unknown>
15: 0x7f1ddb8137c0 - <unknown>
16: 0x7f1ddb80c900 - middle::typeck::check::check_item::h63be73a18b660b1fa8T
17: 0x7f1ddb8135c0 - middle::typeck::check::check_item_types::h37ee3d140fd54ff3jyT
18: 0x7f1ddb2277b0 - <unknown>
19: 0x7f1ddba212e0 - middle::typeck::check_crate::he1d188a32484ea72Lbl
20: 0x7f1ddbaeed60 - driver::driver::phase_3_run_analysis_passes::hbe43a1c4d536fa03SMz
21: 0x7f1ddbae9ea0 - driver::driver::compile_input::h270b0e9df0362e39Yyz
22: 0x7f1ddbb973a0 - <unknown>
23: 0x7f1ddbb972b0 - <unknown>
24: 0x7f1ddbba9ce0 - <unknown>
25: 0x7f1ddbba9ae0 - <unknown>
26: 0x7f1ddaf37220 - <unknown>
27: 0x7f1ddac2ca90 - <unknown>
28: 0x7f1ddac2ca80 - rust_try
29: 0x7f1ddabd8a80 - unwind::try::h34e32f5beb935a03F6d
30: 0x7f1ddabd8820 - task::Task::run::hcd20cd28338e53dfZcd
31: 0x7f1ddaf36fe0 - <unknown>
32: 0x7f1ddabda660 - <unknown>
33: 0x7f1dd59a9060 - start_thread
34: 0x7f1dda8a9489 - __clone
35: 0x0 - <unknown>

Issue 2:
Found this while refactoring my library after the Vector -> Slice rename

STR:

use std::{mem, raw};

fn main() {
let a = &[1, 2, 3i];
let raw::Slice { data: ptr, len: len }: raw::Slice<int> = unsafe { mem::transmute(a) };
let b = unsafe { mem::transmute(Slice { data: ptr, len: len }) };
// ICE ^~~ forgot the `raw::` qualifier
}

Backtrace:

task 'rustc' failed at 'explicit failure', /var/tmp/paludis/build/dev-lang-rust-scm/work/rust-scm/src/librbml/lib.rs:246

stack backtrace:
1: 0x7fadbcf65980 - rt::backtrace::imp::write::h500c7cd49c94d6cbo1q
2: 0x7fadbcf68a20 - <unknown>
3: 0x7fadc14ddc40 - unwind::begin_unwind_inner::h78b0bc3908c6581cM8d
4: 0x7fadc03d5310 - <unknown>
5: 0x7fadc03d4340 - reader::get_doc::h659c9cb63ec6b27dQRa
6: 0x7fadc23b9d40 - metadata::decoder::get_type::h8aa840f508fceb99Bis
7: 0x7fadc1df73b0 - middle::ty::lookup_item_type::h0762f54f39bdc9b9J5G
8: 0x7fadc2154ec0 - <unknown>
9: 0x7fadc2152820 - <unknown>
10: 0x7fadc2154ec0 - <unknown>
11: 0x7fadc211dba0 - <unknown>
12: 0x7fadc2154ec0 - <unknown>
13: 0x7fadc21b39c0 - middle::typeck::check::check_decl_local::h2a1925bfb9a5b157XEW
14: 0x7fadc21b3be0 - middle::typeck::check::check_stmt::he6d6f56b73c868b94GW
15: 0x7fadc211dba0 - <unknown>
16: 0x7fadc2119930 - <unknown>
17: 0x7fadc2119650 - <unknown>
18: 0x7fadc2112510 - middle::typeck::check::check_item::h9d5462bdf5870d8fxhS
19: 0x7fadc2119450 - middle::typeck::check::check_item_types::h60cfbf824eb42ae21HR
20: 0x7fadc1b2a150 - <unknown>
21: 0x7fadc23275c0 - middle::typeck::check_crate::h322ddeef25afc167p2i
22: 0x7fadc23f6af0 - driver::driver::phase_3_run_analysis_passes::h01e8a18355fa9e80Vsx
23: 0x7fadc23f1c30 - driver::driver::compile_input::h7879a63579b438beafx
24: 0x7fadc249d400 - <unknown>
25: 0x7fadc249d310 - <unknown>
26: 0x7fadc24afc60 - <unknown>
27: 0x7fadc24afa60 - <unknown>
28: 0x7fadc1838b30 - <unknown>
29: 0x7fadc152d970 - <unknown>
30: 0x7fadc152d960 - rust_try
31: 0x7fadc14db2a0 - unwind::try::h36697dac480a0e50hXd
32: 0x7fadc14db040 - task::Task::run::h0fb2de2c85c53b00T4c
33: 0x7fadc18388f0 - <unknown>
34: 0x7fadc14dce80 - <unknown>
35: 0x7fadbc2e0000 - start_thread
36: 0x7fadc11ac269 - clone
37: 0x0 - <unknown>

Version:

rustc 0.12.0-pre (a8c8e3f80 2014-08-14 19:11:18 +0000)