ICE on beta and nightly: index out of bounds in RestoreSubsliceArrayMoveOut MIR pass

[koute]

The main crate of our profiler (commit d2ec7ae) stopped compiling on beta and nightly. The stable channel works fine, so this is a regression-from-stable-to-nightly and regression-from-stable-to-beta.

Relevant Travis jobs

nightly (failed) - https://travis-ci.org/nokia/not-perf/jobs/504003420
beta (failed) - https://travis-ci.org/nokia/not-perf/jobs/504003419
stable (which compiles successfully) - https://travis-ci.org/nokia/not-perf/jobs/504003418

Reproduction

$ git clone https://github.com/nokia/not-perf.git
$ cd not-perf
$ cargo build

cargo test and cargo check are fine and do not ICE (which is why I haven't noticed this sooner); only cargo build (both debug and release) is broken.

Compiler output

thread 'rustc' panicked at 'index out of bounds: the len is 3 but the index is 3', /rustc/2a65cbeea78c2c79b1030a0012cdea475104a44f/src/libcore/slice/mod.rs:2545:14
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39
   1: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:71
   2: std::panicking::default_hook::{{closure}}
             at src/libstd/sys_common/backtrace.rs:59
             at src/libstd/panicking.rs:197
   3: std::panicking::default_hook
             at src/libstd/panicking.rs:211
   4: rustc::util::common::panic_hook
   5: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:478
   6: std::panicking::continue_panic_fmt
             at src/libstd/panicking.rs:381
   7: rust_begin_unwind
             at src/libstd/panicking.rs:308
   8: core::panicking::panic_fmt
             at src/libcore/panicking.rs:85
   9: core::panicking::panic_bounds_check
             at src/libcore/panicking.rs:61
  10: rustc::mir::visit::Visitor::visit_place
  11: <rustc_mir::transform::uniform_array_move_out::RestoreDataCollector as rustc::mir::visit::Visitor<'tcx>>::visit_assign
  12: <rustc_mir::transform::uniform_array_move_out::RestoreSubsliceArrayMoveOut as rustc_mir::transform::MirPass>::run_pass
  13: rustc_mir::transform::run_passes::{{closure}}
  14: rustc_mir::transform::run_passes
  15: rustc_mir::transform::optimized_mir
  16: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors<'tcx> for rustc::ty::query::queries::optimized_mir<'tcx>>::compute
  17: rustc::dep_graph::graph::DepGraph::with_task_impl
  18: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::get_query
  19: rustc_mir::monomorphize::collector::collect_items_rec
  20: rustc_mir::monomorphize::collector::collect_items_rec
  21: rustc_mir::monomorphize::collector::collect_items_rec
  22: rustc_mir::monomorphize::collector::collect_items_rec
  23: rustc_mir::monomorphize::collector::collect_items_rec
  24: rustc_mir::monomorphize::collector::collect_items_rec
  25: rustc_mir::monomorphize::collector::collect_crate_mono_items::{{closure}}
  26: rustc::util::common::time
  27: rustc_mir::monomorphize::collector::collect_crate_mono_items
  28: rustc::util::common::time
  29: rustc_mir::monomorphize::partitioning::collect_and_partition_mono_items
  30: rustc::ty::query::__query_compute::collect_and_partition_mono_items
  31: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors<'tcx> for rustc::ty::query::queries::collect_and_partition_mono_items<'tcx>>::compute
  32: rustc::dep_graph::graph::DepGraph::with_task_impl
  33: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::get_query
  34: rustc_codegen_ssa::base::codegen_crate
  35: <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_utils::codegen_backend::CodegenBackend>::codegen_crate
  36: rustc::util::common::time
  37: rustc_driver::driver::phase_4_codegen
  38: <std::thread::local::LocalKey<T>>::with
  39: rustc::ty::context::TyCtxt::create_and_enter
  40: rustc_driver::driver::compile_input
  41: rustc_driver::run_compiler_with_pool
  42: <scoped_tls::ScopedKey<T>>::set
  43: rustc_driver::run_compiler
  44: syntax::with_globals
  45: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:87
  46: <F as alloc::boxed::FnBox<A>>::call_box
  47: std::sys::unix::thread::Thread::new::thread_start
             at /rustc/2a65cbeea78c2c79b1030a0012cdea475104a44f/src/liballoc/boxed.rs:759
             at src/libstd/sys_common/thread.rs:14
             at src/libstd/sys/unix/thread.rs:80
  48: start_thread
  49: clone
query stack during panic:
#0 [optimized_mir] processing `ps::wait_for_process`
#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 1.35.0-nightly (2a65cbeea 2019-03-08) running on x86_64-unknown-linux-gnu
note: compiler flags: -C debuginfo=2 -C incremental --crate-type bin
note: some of the compiler flags provided by cargo are hidden
error: Could not compile `nperf`.

Affected rustc versions

rustc 1.35.0-nightly (2a65cbe 2019-03-08)
rustc 1.34.0-beta.1 (744b374 2019-02-26)

[estebank]

Interestingly, running with RUST_LOG=debug, I don't get the panic, but a cycle error:

DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: instantiate_poly_trait_ref(TraitRef { path: path(Iterator<Item = PathBuf>), hir_ref_id: HirId { owner: DefIndex(1:115), local_id: 5 } }, def_id=DefId(2/0:2158 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]))
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: create_substs_for_ast_trait_ref(trait_segment=PathSegment { ident: Iterator#0, hir_id: Some(HirId { owner: DefIndex(1:115), local_id: 4 }), def: Some(Trait(DefId(2/0:2158 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]))), args: Some(GenericArgs { args: [], bindings: [TypeBinding { hir_id: HirId { owner: DefIndex(1:115), local_id: 1 }, ident: Item#0, ty: type(PathBuf), span: src/mount_info.rs:226:91: 226:105 }], parenthesized: false }), infer_types: false })
error[E0391]: cycle detected when processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`
   --> src/mount_info.rs:226:76
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |                                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
note: ...which requires processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`...
   --> src/mount_info.rs:226:76
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |                                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: ...which requires processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`...
   --> src/mount_info.rs:226:76
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |                                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = note: ...which again requires processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`, completing the cycle
note: cycle used when processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve`
   --> src/mount_info.rs:226:5
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: create_substs_for_ast_path(def_id=DefId(2/0:2158 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]), self_ty=Some(impl ?Sized), generic_args=GenericArgs { args: [], bindings: [TypeBinding { hir_id: HirId { owner: DefIndex(1:115), local_id: 1 }, ident: Item#0, ty: type(PathBuf), span: src/mount_info.rs:226:91: 226:105 }], parenthesized: false })
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: check_kind_count: kind: lifetime required: 0 permitted: 0 provided: 0 offset: 0
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: check_kind_count: kind: const required: 0 permitted: 0 provided: 0 offset: 0
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: check_kind_count: kind: type required: 0 permitted: 0 provided: 0 offset: 0
DEBUG 2019-03-09T19:35:06Z: rustc::ty::fold: HasTypeFlagsVisitor: t=impl ?Sized t.flags=HAS_PARAMS | HAS_RE_EARLY_BOUND | HAS_FREE_REGIONS | HAS_PROJECTION | HAS_FREE_LOCAL_NAMES self.flags=KEEP_IN_LOCAL_TCX
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: ast_ty_to_ty(id=HirId { owner: DefIndex(1:115), local_id: 2 }, ast_ty=type(PathBuf) ty_ty=Path(Resolved(None, path(PathBuf))))
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: ast_ty_to_ty: maybe_qself=None path=path(PathBuf)
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: def_to_ty(def=Struct(DefId(1/0:5192 ~ std[c57b]::path[0]::PathBuf[0])), opt_self_ty=None, path_segments=[PathSegment { ident: PathBuf#0, hir_id: Some(HirId { owner: DefIndex(1:115), local_id: 3 }), def: Some(Err), args: None, infer_types: false }])
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: create_substs_for_ast_path(def_id=DefId(1/0:5192 ~ std[c57b]::path[0]::PathBuf[0]), self_ty=None, generic_args=GenericArgs { args: [], bindings: [], parenthesized: false })
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: check_kind_count: kind: lifetime required: 0 permitted: 0 provided: 0 offset: 0
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: check_kind_count: kind: const required: 0 permitted: 0 provided: 0 offset: 0
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: check_kind_count: kind: type required: 0 permitted: 0 provided: 0 offset: 0
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: create_substs_for_ast_path(generic_params=Generics { parent: None, parent_count: 0, params: [], param_def_id_to_index: {}, has_self: false, has_late_bound_regions: None }, self_ty=None) -> []
DEBUG 2019-03-09T19:35:06Z: rustc::ty::fold: HasTypeFlagsVisitor: t=std::path::PathBuf t.flags=(empty) self.flags=HAS_PARAMS | HAS_SELF | HAS_RE_EARLY_BOUND | NEEDS_SUBST
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: create_substs_for_ast_path(generic_params=Generics { parent: None, parent_count: 0, params: [Type(Self, DefId(2/0:2158 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]), 0)], param_def_id_to_index: {DefId(2/0:2158 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]): 0}, has_self: true, has_late_bound_regions: None }, self_ty=Some(impl ?Sized)) -> [impl ?Sized]
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: late_bound_in_trait_ref = {}
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: late_bound_in_ty = {}
DEBUG 2019-03-09T19:35:06Z: rustc::middle::stability: stability: inspecting def_id=DefId(2/0:2159 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]::Item[0]) span=src/mount_info.rs:226:91: 226:105 of stability=Some(Stability { level: Stable { since: 1.0.0 }, feature: rust1, rustc_depr: None, const_stability: None, promotable: false })
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: instantiate_poly_trait_ref(TraitRef { path: path(Iterator<Item = PathBuf>), hir_ref_id: HirId { owner: DefIndex(1:115), local_id: 5 } }, projections=[(Binder(ProjectionPredicate(ProjectionTy { substs: [impl ?Sized], item_def_id: DefId(2/0:2159 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]::Item[0]) }, std::path::PathBuf)), src/mount_info.rs:226:91: 226:105)]) -> Binder(<impl ?Sized as std::iter::Iterator>)
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::astconv: ast_region_to_region(lifetime=lifetime(HirId { owner: DefIndex(1:115), local_id: 6 }: 'a)) yields ReEarlyBound(1, 'a)
DEBUG 2019-03-09T19:35:06Z: rustc::ty::fold: HasTypeFlagsVisitor: t=impl ?Sized t.flags=HAS_PARAMS | HAS_RE_EARLY_BOUND | HAS_FREE_REGIONS | HAS_PROJECTION | HAS_FREE_LOCAL_NAMES self.flags=KEEP_IN_LOCAL_TCX
error[E0391]: cycle detected when processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`
   --> src/mount_info.rs:226:76
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |                                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
note: ...which requires processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`...
   --> src/mount_info.rs:226:76
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |                                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = note: ...which again requires processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`, completing the cycle
note: cycle used when processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve`
   --> src/mount_info.rs:226:5
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::collect: predicates_defined_on: explicit_predicates_of(DefId(0/1:115 ~ nperf[6bb5]::mount_info[0]::{{impl}}[5]::resolve[0]::{{impl-Trait}}[0])) = GenericPredicates([(Binder(TraitPredicate(<impl ?Sized as std::marker::Sized>)), src/mount_info.rs:226:76: 226:112), (Binder(OutlivesPredicate(impl ?Sized, ReEarlyBound(1, 'a))), src/mount_info.rs:226:110: 226:112), (Binder(TraitPredicate(<impl ?Sized as std::iter::Iterator>)), src/mount_info.rs:226:81: 226:107), (Binder(ProjectionPredicate(ProjectionTy { substs: [impl ?Sized], item_def_id: DefId(2/0:2159 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]::Item[0]) }, std::path::PathBuf)), src/mount_info.rs:226:91: 226:105)])
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::collect: predicates_defined_on(DefId(0/1:115 ~ nperf[6bb5]::mount_info[0]::{{impl}}[5]::resolve[0]::{{impl-Trait}}[0])) = GenericPredicates([(Binder(TraitPredicate(<impl ?Sized as std::marker::Sized>)), src/mount_info.rs:226:76: 226:112), (Binder(OutlivesPredicate(impl ?Sized, ReEarlyBound(1, 'a))), src/mount_info.rs:226:110: 226:112), (Binder(TraitPredicate(<impl ?Sized as std::iter::Iterator>)), src/mount_info.rs:226:81: 226:107), (Binder(ProjectionPredicate(ProjectionTy { substs: [impl ?Sized], item_def_id: DefId(2/0:2159 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]::Item[0]) }, std::path::PathBuf)), src/mount_info.rs:226:91: 226:105)])
error[E0391]: cycle detected when processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`
   --> src/mount_info.rs:226:76
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |                                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: ...which again requires processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve::{{impl-Trait}}`, completing the cycle
note: cycle used when processing `mount_info::<impl at src/mount_info.rs:195:1: 246:2>::resolve`
   --> src/mount_info.rs:226:5
    |
226 |     pub fn resolve< 'a, P: AsRef< Path > >( &'a self, path: P ) -> Option< impl Iterator< Item = PathBuf > + 'a > {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
DEBUG 2019-03-09T19:35:06Z: rustc_typeck::collect: predicates_of(def_id=DefId(0/1:115 ~ nperf[6bb5]::mount_info[0]::{{impl}}[5]::resolve[0]::{{impl-Trait}}[0])) = GenericPredicates([(Binder(TraitPredicate(<impl ?Sized as std::marker::Sized>)), src/mount_info.rs:226:76: 226:112), (Binder(OutlivesPredicate(impl ?Sized, ReEarlyBound(1, 'a))), src/mount_info.rs:226:110: 226:112), (Binder(TraitPredicate(<impl ?Sized as std::iter::Iterator>)), src/mount_info.rs:226:81: 226:107), (Binder(ProjectionPredicate(ProjectionTy { substs: [impl ?Sized], item_def_id: DefId(2/0:2159 ~ core[284b]::iter[0]::traits[0]::iterator[0]::Iterator[0]::Item[0]) }, std::path::PathBuf)), src/mount_info.rs:226:91: 226:105)])
thread 'rustc' has overflowed its stack
fatal runtime error: stack overflow
[2019-03-09T19:37:29Z DEBUG cargo] exit_with_error; err=CliError { error: Some(ProcessError { desc: "process didn\'t exit successfully: `rustc --crate-name nperf src/main.rs --color never --crate-type bin --emit=dep-info,link -C debuginfo=2 --cfg \'feature=\"default\"\' --cfg \'feature=\"logging\"\' --cfg \'feature=\"nwind\"\' -C metadata=f040a09e21ff6e26 -C extra-filename=-f040a09e21ff6e26 --out-dir /Users/ekuber/personal/not-perf/target/debug/deps -C incremental=/Users/ekuber/personal/not-perf/target/debug/incremental -L dependency=/Users/ekuber/personal/not-perf/target/debug/deps --extern chrono=/Users/ekuber/personal/not-perf/target/debug/deps/libchrono-5ff88e354277f83f.rlib --extern env_logger=/Users/ekuber/personal/not-perf/target/debug/deps/libenv_logger-78c077948f2c02ce.rlib --extern lazy_static=/Users/ekuber/personal/not-perf/target/debug/deps/liblazy_static-ad42470069693248.rlib --extern libc=/Users/ekuber/personal/not-perf/target/debug/deps/liblibc-6a79fbdcb2893d3f.rlib --extern log=/Users/ekuber/personal/not-perf/target/debug/deps/liblog-bf648d25a1b76985.rlib --extern nperf=/Users/ekuber/personal/not-perf/target/debug/deps/libnperf-3b4c16f1b25149b2.rlib --extern num_cpus=/Users/ekuber/personal/not-perf/target/debug/deps/libnum_cpus-296401efbf15c812.rlib --extern nwind=/Users/ekuber/personal/not-perf/target/debug/deps/libnwind-520014cbc8c13870.rlib --extern parking_lot=/Users/ekuber/personal/not-perf/target/debug/deps/libparking_lot-4d5bb6c64055548b.rlib --extern perf_event_open=/Users/ekuber/personal/not-perf/target/debug/deps/libperf_event_open-f6968ba9ab7abf76.rlib --extern proc_maps=/Users/ekuber/personal/not-perf/target/debug/deps/libproc_maps-2626b87765fa0129.rlib --extern regex=/Users/ekuber/personal/not-perf/target/debug/deps/libregex-7c1527dad8c6100a.rlib --extern serde=/Users/ekuber/personal/not-perf/target/debug/deps/libserde-1b9624f31c5af207.rlib --extern serde_derive=/Users/ekuber/personal/not-perf/target/debug/deps/libserde_derive-743003eaf65dae3a.dylib --extern serde_json=/Users/ekuber/personal/not-perf/target/debug/deps/libserde_json-88b42f27d496342d.rlib --extern speedy=/Users/ekuber/personal/not-perf/target/debug/deps/libspeedy-a7d7df9a114a8bee.rlib --extern speedy_derive=/Users/ekuber/personal/not-perf/target/debug/deps/libspeedy_derive-af1054e99f3503c8.dylib --extern structopt=/Users/ekuber/personal/not-perf/target/debug/deps/libstructopt-42fb8d13ffa79d89.rlib` (signal: 6, SIGABRT: process abort signal)", exit: Some(ExitStatus(ExitStatus(6))), output: None }

[Dylan-DPC-zz]

I saw the same issue on a crater run:
Log: https://crater-reports.s3.amazonaws.com/beta-1.34-1/beta-2019-02-27/gh/viperscape.capsule/log.txt

cc @viperscape (though the crate looks abandoned but still keeping you in loop)

[viperscape]

Thanks for the heads up, it's just a skeleton app for creating basic LDAP connections via a web browser, so it's more of an example. Stable compiles and runs fine.

[pnkfelix]

triage: P-high due to being stable-to-beta regression and an ICE

[pnkfelix]

assigning to @nikomatsakis to bisect.

[nikomatsakis]

Hmm, I am not able to reproduce this with the latest nightly.

[nikomatsakis]

Attempting with beta.

[nikomatsakis]

athena. rustc +nightly -vV
rustc 1.35.0-nightly (82e2f3ec2 2019-03-20)
binary: rustc
commit-hash: 82e2f3ec25a316c7536c33a6b6704366b14cbf2a
commit-date: 2019-03-20
host: x86_64-unknown-linux-gnu
release: 1.35.0-nightly
LLVM version: 8.0
athena. rustc +beta -vV
rustc 1.34.0-beta.5 (d049c7baa 2019-03-19)
binary: rustc
commit-hash: d049c7baa701c412850743c8f1f767e264a225ec
commit-date: 2019-03-19
host: x86_64-unknown-linux-gnu
release: 1.34.0-beta.5
LLVM version: 8.0

yeah I was not able to reproduce, on linux, building the commit d2ec7ae :(

[nikomatsakis]

I'm unassigning myself for the time being, since my main goal was to bisect here. I will perhaps try to reproduce on another platform (e.g., windows).

But if you can reproduce, can somebody try using https://github.com/rust-lang-nursery/cargo-bisect-rustc to narrow this down to a specific PR?

[lqd]

(This crate doesn't build on windows AFAICT so don't try to bisect there)

I can reproduce the ICE, and cargo-bisect-rustc seems to narrow this down to:

• nightly-2019-02-16
• commit f058741, for PR rustc_mir: split qualify_consts' "value qualification" bitflags into separate computations. #58403

However, as Niko mentioned, I can't repro either on the latest nightly. I think it has since been fixed some time between nightly-2019-03-10 and nightly-2019-03-15 (the last ones I manually checked).

---

Update — I've now also bisected the fix:

• nightly-2019-03-12
• commit c2ddf5a, for PR Don't promote function calls to nonpromotable things #58784

[oli-obk]

Thanks for the ICE and fix bisection.