rustc fails to build, again

rustc_build_failure_redux.txt

zmd@ReflectiveCoherence:~/Code/rust$ RUST_BACKTRACE=full ./x.py test --stage 1
Updating only changed submodules
Submodules updated in 0.03 seconds
    Finished dev [unoptimized] target(s) in 0.20s
Building stage0 std artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Finished release [optimized] target(s) in 0.18s
Copying stage0 std from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-gnu)
Building stage0 tool tidy (x86_64-unknown-linux-gnu)
    Finished release [optimized] target(s) in 0.17s
tidy check
* 547 error codes
* highest error code: E0702
* 206 features
Building stage0 test artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Finished release [optimized] target(s) in 0.17s
Copying stage0 test from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-gnu)
Building stage0 compiler artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Finished release [optimized] target(s) in 0.20s
Copying stage0 rustc from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-gnu)
Building stage0 codegen artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu, llvm)
    Finished release [optimized] target(s) in 0.20s
Assembling stage1 compiler (x86_64-unknown-linux-gnu)
Building stage1 std artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
   Compiling std v0.0.0 (file:///home/zmd/Code/rust/src/libstd)
thread 'main' panicked at 'internal error: entered unreachable code', librustc/middle/const_val.rs:27:52
stack backtrace:
   0:     0x7f126a8a7c2e - std::sys::unix::backtrace::tracing::imp::unwind_backtrace::ha82b397ea71be585
   1:     0x7f126a87df56 - std::sys_common::backtrace::print::h0f02aefa57d1295d
   2:     0x7f126a87be4d - std::panicking::default_hook::{{closure}}::hb248860985868cdd
   3:     0x7f126a87bbc0 - std::panicking::default_hook::h0dd63170d2171fd8
   4:     0x7f1266df2955 - rustc::util::common::panic_hook::hb6ff0348b425b2da
   5:     0x7f126a87c4d3 - std::panicking::rust_panic_with_hook::h3ca8500cc05677cc
   6:     0x7f12689c46e6 - std::panicking::begin_panic::h4551821a8cff9062
   7:     0x7f1268a41ab9 - serialize::serialize::Decoder::read_enum::h9af3f2080eaabfe9
   8:     0x7f1268a3a71c - serialize::serialize::Decoder::read_enum::h4cf5bc755f5bb52c
   9:     0x7f1268a20c2b - serialize::serialize::Decoder::read_struct::h77c791979a4d7727
  10:     0x7f12689d87c8 - <alloc::boxed::Box<T> as serialize::serialize::Decodable>::decode::h479f47375427af9a
  11:     0x7f1268a43e4a - serialize::serialize::Decoder::read_enum::he68d7bfc14f5db3f
  12:     0x7f1268a35fd3 - serialize::serialize::Decoder::read_enum::h208fcb6db2ba7bf6
  13:     0x7f1268a2a51b - serialize::serialize::Decoder::read_struct::hef160df5711e17cf
  14:     0x7f1268a2aec5 - serialize::serialize::Decoder::read_struct::hfb827ac30cac547e
  15:     0x7f1268a2d4fa - serialize::serialize::Decoder::read_seq::h3f681f16bc5dd485
  16:     0x7f1268a11bf3 - <rustc::mir::Mir<'tcx> as serialize::serialize::Decodable>::decode::{{closure}}::h87e5360d31115845
  17:     0x7f1268a7a5de - rustc_metadata::decoder::<impl rustc_metadata::cstore::CrateMetadata>::maybe_get_optimized_mir::hfd051fd50b3cd02b
  18:     0x7f12689a023e - rustc_metadata::cstore_impl::provide_extern::optimized_mir::h2df4548810242052
  19:     0x7f1266dfc702 - rustc::ty::query::__query_compute::optimized_mir::h0a0c35602c764103
  20:     0x7f1266b069fc - rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors<'tcx> for rustc::ty::query::queries::optimized_mir<'tcx>>::compute::h85b3c5e6f2670170
  21:     0x7f126692c997 - rustc::dep_graph::graph::DepGraph::with_task_impl::h09d95d2598e7f53f
  22:     0x7f1266af5856 - rustc::ty::context::tls::with_related_context::he9c998219ed1a798
  23:     0x7f1266bf1b36 - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::force_query_with_job::h08e702cd75960ddf
  24:     0x7f1266c4adf3 - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_get_query::h2a158d7ab4141d91
  25:     0x7f1266d304de - rustc::ty::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::instance_mir::hb235bf8b75a7f32d
  26:     0x7f1267af66ea - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  27:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  28:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  29:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  30:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  31:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  32:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  33:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  34:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  35:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  36:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  37:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  38:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  39:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  40:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  41:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  42:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  43:     0x7f1267af62fd - rustc_mir::monomorphize::collector::collect_items_rec::ha1f431d47ceab825
  44:     0x7f1267af56cc - rustc_mir::monomorphize::collector::collect_crate_mono_items::{{closure}}::h1226e28ff620f76b
  45:     0x7f1267af4d41 - rustc_mir::monomorphize::collector::collect_crate_mono_items::h0c50e2f305e2af14
  46:     0x7f12605cbd66 - rustc::util::common::time::hbc3fab16463b3015
  47:     0x7f126069c91b - rustc_codegen_llvm::base::collect_and_partition_mono_items::hd98e2987bfc92aa8
  48:     0x7f1266b07bb8 - rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors<'tcx> for rustc::ty::query::queries::collect_and_partition_mono_items<'tcx>>::compute::hae7ff58b31d9180f
  49:     0x7f1266971191 - rustc::dep_graph::graph::DepGraph::with_task_impl::he1c6e3c3f7350407
  50:     0x7f1266a9e1fb - rustc::ty::context::tls::with_related_context::h07e86ddac8f40d45
  51:     0x7f1266c06b84 - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::force_query_with_job::h8e6d3a6890adc879
  52:     0x7f1266d189d5 - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::get_query::hfd07b747f3ccaf44
  53:     0x7f126069ab5c - rustc_codegen_llvm::base::codegen_crate::h5670836a40720b3c
  54:     0x7f12606878cf - <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_utils::codegen_backend::CodegenBackend>::codegen_crate::ha566d4acdfa03abe
  55:     0x7f126ac05f91 - rustc::util::common::time::hb7516c4646310f1b
  56:     0x7f126abf817c - rustc_driver::driver::phase_4_codegen::hb7f9f64c8ea6a597
  57:     0x7f126acb9ebc - rustc_driver::driver::compile_input::{{closure}}::h283d259e2cb4625d
  58:     0x7f126acb039b - rustc::ty::context::tls::enter_context::hdb861e03b8b0ae91
  59:     0x7f126ac55203 - <std::thread::local::LocalKey<T>>::with::h8d21dad7ad798818
  60:     0x7f126abaa05f - rustc::ty::context::TyCtxt::create_and_enter::h34982de6f80af0f5
  61:     0x7f126abf17e0 - rustc_driver::driver::compile_input::hf82b98d1eaacb9f2
  62:     0x7f126ac9117d - rustc_driver::run_compiler_with_pool::hcfe32efd5fcfccf9
  63:     0x7f126abdfa2f - <scoped_tls::ScopedKey<T>>::set::he6b9ced4e80f4d49
  64:     0x7f126abb3edd - syntax::with_globals::hb2934ce56dafdfc8
  65:     0x7f126ab928e2 - <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::h2ade8b781055e814
  66:     0x7f126a8bab49 - __rust_maybe_catch_panic
  67:     0x7f126ac8e403 - rustc_driver::run::h7cc2209434393e4c
  68:     0x7f126ac9de9a - rustc_driver::main::hd162f8316dee09ee
  69:     0x556ff1599b22 - std::rt::lang_start::{{closure}}::hb128da4cc9ee8b09
  70:     0x7f126a87c012 - std::panicking::try::do_call::h5d13bd17c519af69
  71:     0x7f126a8bab49 - __rust_maybe_catch_panic
  72:     0x7f126a870e15 - std::rt::lang_start_internal::he15214c0a1fdba94
  73:     0x556ff1599b83 - main
  74:     0x7f126a48082f - __libc_start_main
  75:     0x556ff1599a18 - _start
  76:                0x0 - <unknown>
query stack during panic:
#0 [optimized_mir] processing `<core::ops::Range<usize> as core::slice::SliceIndex<[T]>>::index_mut`
#1 [collect_and_partition_mono_items] collect_and_partition_mono_items
end of query stack

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: rustc 1.28.0-dev running on x86_64-unknown-linux-gnu

note: compiler flags: -Z force-unstable-if-unmarked -C prefer-dynamic -C opt-level=2 -C prefer-dynamic -C debug-assertions=n -C link-args=-Wl,-rpath,$ORIGIN/../lib --crate-type dylib --crate-type rlib

note: some of the compiler flags provided by cargo are hidden

error: Could not compile `std`.

Caused by:
  process didn't exit successfully: `/home/zmd/Code/rust/build/bootstrap/debug/rustc --crate-name std libstd/lib.rs --error-format json --crate-type dylib --crate-type rlib --emit=dep-info,link -C prefer-dynamic -C opt-level=2 --cfg feature="alloc_jemalloc" --cfg feature="backtrace" --cfg feature="jemalloc" --cfg feature="panic-unwind" --cfg feature="panic_unwind" -C metadata=1a86a61763c2b34b -C extra-filename=-1a86a61763c2b34b --out-dir /home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps --target x86_64-unknown-linux-gnu -L dependency=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps -L dependency=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/release/deps --extern libc=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/liblibc-8a689bacec06a191.rlib --extern panic_abort=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/libpanic_abort-dbdbba248951650b.rlib --extern compiler_builtins=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/libcompiler_builtins-371c588c1a3805de.rlib --extern rustc_msan=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/librustc_msan-f42f9ae0d9b3b245.rlib --extern alloc=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/liballoc-057d09441be39ab5.rlib --extern rustc_lsan=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/librustc_lsan-613111e9987dd34b.rlib --extern unwind=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/libunwind-e8ee297dbe25844d.rlib --extern core=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/libcore-b8b7fb254e56b0ab.rlib --extern rustc_asan=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/librustc_asan-0983f738af9f329b.rlib --extern alloc_system=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/liballoc_system-5e948e8e93b206b3.rlib --extern std_unicode=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/libstd_unicode-9cb32559fd090f4f.rlib --extern rustc_tsan=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/librustc_tsan-00347be741ae2593.rlib --extern panic_unwind=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/libpanic_unwind-339c04ae4132d76c.rlib --extern alloc_jemalloc=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/deps/liballoc_jemalloc-eb1d26a1b5f469f1.rlib -L native=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/native/libbacktrace/ -l static=backtrace -l dl -l rt -l pthread -L native=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/build/compiler_builtins-f3f01c545fe8aed7/out -L native=/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/native/jemalloc/lib` (exit code: 101)
command did not execute successfully: "/home/zmd/Code/rust/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "build" "--target" "x86_64-unknown-linux-gnu" "-j" "12" "--release" "--features" "panic-unwind jemalloc backtrace" "--manifest-path" "/home/zmd/Code/rust/src/libstd/Cargo.toml" "--message-format" "json"
expected success, got: exit code: 101
thread 'main' panicked at 'cargo must succeed', bootstrap/compile.rs:1091:9
stack backtrace:
   0:     0x56433f0c256e - std::sys::unix::backtrace::tracing::imp::unwind_backtrace::h7b0b352473fc3af4
                               at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1:     0x56433f0cbcb6 - std::sys_common::backtrace::print::he3cf3cd3410b9fcd
                               at libstd/sys_common/backtrace.rs:71
                               at libstd/sys_common/backtrace.rs:59
   2:     0x56433f0ad27b - std::panicking::default_hook::{{closure}}::ha93173e7a7a43c1d
                               at libstd/panicking.rs:211
   3:     0x56433f0acf53 - std::panicking::default_hook::h1407d21ad31eecbe
                               at libstd/panicking.rs:227
   4:     0x56433f0ad89e - std::panicking::rust_panic_with_hook::h3369dbee6150f56a
                               at libstd/panicking.rs:463
   5:     0x56433efa4a2f - std::panicking::begin_panic::ha8a1759c614c0ce5
                               at /checkout/src/libstd/panicking.rs:397
   6:     0x56433e773674 - bootstrap::compile::run_cargo::hbdadbe8e431c9bf1
                               at bootstrap/compile.rs:1091
   7:     0x56433e767d4f - <bootstrap::compile::Std as bootstrap::builder::Step>::run::h8f27547766a7e5ce
                               at bootstrap/compile.rs:109
   8:     0x56433eeb4302 - bootstrap::builder::Builder::ensure::h8fd168a7747e064a
                               at bootstrap/builder.rs:1110
   9:     0x56433e76a618 - <bootstrap::compile::Test as bootstrap::builder::Step>::run::h899f8c3b3aa79778
                               at bootstrap/compile.rs:354
  10:     0x56433ee26bc2 - bootstrap::builder::Builder::ensure::h0f2e883ddfe9ba21
                               at bootstrap/builder.rs:1110
  11:     0x56433ea36b94 - <bootstrap::test::Compiletest as bootstrap::builder::Step>::run::h6f2526130f643065
                               at bootstrap/test.rs:969
  12:     0x56433eec054c - bootstrap::builder::Builder::ensure::h9f3473d68d352ca8
                               at bootstrap/builder.rs:1110
  13:     0x56433ea42f55 - <bootstrap::test::Ui as bootstrap::builder::Step>::run::h8b9a64f3f6c08190
                               at bootstrap/test.rs:727
  14:     0x56433ee7ba62 - bootstrap::builder::Builder::ensure::h58c3d79a783e8061
                               at bootstrap/builder.rs:1110
  15:     0x56433ea42e68 - <bootstrap::test::Ui as bootstrap::builder::Step>::make_run::h75f6f4dd63a97f1a
                               at bootstrap/test.rs:720
  16:     0x56433e77acb6 - bootstrap::builder::StepDescription::maybe_run::hdb50ccdd0b72dd5b
                               at bootstrap/builder.rs:191
  17:     0x56433e77b347 - bootstrap::builder::StepDescription::run::hfd1c77be9845c3d0
                               at bootstrap/builder.rs:215
  18:     0x56433e77fe78 - bootstrap::builder::Builder::run_step_descriptions::h0eff0284310bd176
                               at bootstrap/builder.rs:562
  19:     0x56433e77fcd1 - bootstrap::builder::Builder::execute_cli::h3801ed1edbc638aa
                               at bootstrap/builder.rs:552
  20:     0x56433eaba379 - bootstrap::Build::build::h8046c4db5e3a84b4
                               at bootstrap/lib.rs:450
  21:     0x56433e72cba0 - bootstrap::main::h330e04edb7d91bae
                               at bootstrap/bin/main.rs:29
  22:     0x56433e72c56f - std::rt::lang_start::{{closure}}::h891028e74795f5ba
                               at /checkout/src/libstd/rt.rs:74
  23:     0x56433f0ad382 - std::panicking::try::do_call::h21ad9e7b3d9e9c06
                               at libstd/rt.rs:59
                               at libstd/panicking.rs:310
  24:     0x56433f0d2d39 - __rust_maybe_catch_panic
                               at libpanic_unwind/lib.rs:105
  25:     0x56433f0b92f5 - std::rt::lang_start_internal::hf7717a94b85ee59f
                               at libstd/panicking.rs:289
                               at libstd/panic.rs:374
                               at libstd/rt.rs:58
  26:     0x56433e72c547 - std::rt::lang_start::hc3b51ee8a4597f34
                               at /checkout/src/libstd/rt.rs:74
  27:     0x56433e72cc2c - main
  28:     0x7fd4077e382f - __libc_start_main
  29:     0x56433e72a308 - _start
  30:                0x0 - <unknown>
failed to run: /home/zmd/Code/rust/build/bootstrap/debug/bootstrap test --stage 1
Build completed unsuccessfully in 0:00:08