Unexpected Compiler Panic

When compiling the latest release of Redox, the nightly release of the compiler panicked. The output of attempting to make all in redox is below:

mkdir -p build/i386-unknown-redox/debug
RUST_BACKTRACE=1 rustc --target=i386-unknown-redox.json -L build/i386-unknown-redox/debug -C no-prepopulate-passes -C no-stack-check -C opt-level=2 -Z no-landing-pads -A dead_code -o build/i386-unknown-redox/debug/libcore.rlib rust/src/libcore/lib.rs
RUST_BACKTRACE=1 rustc --target=i386-unknown-redox.json -L build/i386-unknown-redox/debug -C no-prepopulate-passes -C no-stack-check -C opt-level=2 -Z no-landing-pads -A dead_code -o build/i386-unknown-redox/debug/liballoc_system.rlib liballoc_system/lib.rs
RUST_BACKTRACE=1 rustc --target=i386-unknown-redox.json -L build/i386-unknown-redox/debug -C no-prepopulate-passes -C no-stack-check -C opt-level=2 -Z no-landing-pads -A dead_code -o build/i386-unknown-redox/debug/liballoc.rlib rust/src/liballoc/lib.rs
thread 'rustc' panicked at 'box_free language item is missing', ../src/libcore/option.rs:704
stack backtrace:
   1:     0x2b5cee1b5850 - sys::backtrace::tracing::imp::write::he15d7b3364c6e91ettu
   2:     0x2b5cee1bd3bb - panicking::default_handler::_$u7b$$u7b$closure$u7d$$u7d$::closure.43190
   3:     0x2b5cee1bcf13 - panicking::default_handler::hd4b9dd3c40d2e5f3fWy
   4:     0x2b5cee186dfc - sys_common::unwind::begin_unwind_inner::h63382e2c0ae54a7diit
   5:     0x2b5cee187898 - sys_common::unwind::begin_unwind_fmt::h0a6a5420714a72c0oht
   6:     0x2b5cee1b3351 - rust_begin_unwind
   7:     0x2b5cee203dbf - panicking::panic_fmt::h1951bd5aee0da5596YL
   8:     0x2b5cee2238c4 - option::expect_failed::h9cc346d7ce275f32ftO
   9:     0x2b5cf0193e1a - build::scope::Builder<'a, 'tcx>::diverge_cleanup::h5ea749b11c66ba65Had
  10:     0x2b5cf0172b80 - build::scope::Builder<'a, 'tcx>::pop_scope::h7568796be110735ff0c
  11:     0x2b5cf018df14 - build::expr::into::Builder<'a, 'tcx>::into_expr::h7a0c025e98fb02bc57a
  12:     0x2b5cf018811c - build::expr::as_rvalue::Builder<'a, 'tcx>::expr_as_rvalue::_$u7b$$u7b$closure$u7d$$u7d$::closure.19089
  13:     0x2b5cf017f59d - build::expr::as_rvalue::Builder<'a, 'tcx>::expr_as_rvalue::h369a28f5cfcac23foCa
  14:     0x2b5cf018d723 - build::expr::into::Builder<'a, 'tcx>::into_expr::h7a0c025e98fb02bc57a
  15:     0x2b5cf01762ae - build::into::ExprRef<'tcx>.EvalInto<'tcx>::eval_into::h374a28606d32aa0f9pb
  16:     0x2b5cf018df03 - build::expr::into::Builder<'a, 'tcx>::into_expr::h7a0c025e98fb02bc57a
  17:     0x2b5cf01762ae - build::into::ExprRef<'tcx>.EvalInto<'tcx>::eval_into::h374a28606d32aa0f9pb
  18:     0x2b5cf0173ca9 - build::block::Builder<'a, 'tcx>::ast_block::hd0f0337c8ad9f41aCka
  19:     0x2b5cf016f628 - build::construct::h90612f4a0cd2dacadca
  20:     0x2b5cf01b955e - mir_map::InnerDump<'a, 'm, 'tcx>.Visitor<'tcx>::visit_fn::h33270291c27d9d1bnqg
  21:     0x2b5cf01c0e67 - mir_map::OuterDump<'a, 'tcx>.Visitor<'tcx>::visit_impl_item::h42dd307c5851c990Pog
  22:     0x2b5cf01b79a1 - mir_map::OuterDump<'a, 'tcx>.Visitor<'tcx>::visit_item::h4fe9ad6dd68a9befyng
  23:     0x2b5cf01b69eb - mir_map::build_mir_for_crate::h560c842fe7acd737Ilg
  24:     0x2b5ceddc08bf - driver::phase_3_run_analysis_passes::_$u7b$$u7b$closure$u7d$$u7d$::closure.27872
  25:     0x2b5ceddbc7ae - middle::ty::context::ctxt<'tcx>::create_and_enter::h11600905232178369135
  26:     0x2b5ceddb8903 - driver::phase_3_run_analysis_passes::h18126472581767654397
  27:     0x2b5cedd8c038 - driver::compile_input::hfa329d5d8fe427ccBca
  28:     0x2b5cedd7c3b8 - run_compiler::hdaf245d1b59a9fc0QGc
  29:     0x2b5cedd798a1 - sys_common::unwind::try::try_fn::h5118579457423020331
  30:     0x2b5cee1b32db - __rust_try
  31:     0x2b5cee1ab81d - sys_common::unwind::inner_try::hc860e6d6d8228b31kft
  32:     0x2b5cedd7a0f0 - boxed::F.FnBox<A>::call_box::h9365687296754034372
  33:     0x2b5cee1bb980 - sys::thread::Thread::new::thread_start::h40f537715d102aa8zTx
  34:     0x2b5cf5baf181 - start_thread
  35:     0x2b5cee76247c - __clone
  36:                0x0 - <unknown>

rustc --version --verbose output:

rustc 1.8.0-nightly (3623797eb 2016-02-07)
binary: rustc
commit-hash: 3623797ebb9674322c4cfcfb0bb7b002afe17f11
commit-date: 2016-02-07
host: x86_64-unknown-linux-gnu
release: 1.8.0-nightly```

[jonas-schievink]

Not a bug, redox has to define the lang item.

Okay, thanks for the info