gfx_device_gl internal compiler error

[Johnson-A]

Using the nightly rustc 1.9.0-nightly (6e0f2f2 2016-03-16), the crate gfx_device_gl fails to compile

Build failed, waiting for other jobs to finish...
       error Could not compile `gfx_device_gl`.

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
thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', ../src/libcore/option.rs:330
stack backtrace:
   1:     0x7f5effd14240 - sys::backtrace::tracing::imp::write::h3bbb320d569781f92cv
   2:     0x7f5effd1e43f - panicking::default_handler::_$u7b$$u7b$closure$u7d$$u7d$::closure.44520
   3:     0x7f5effd1dfb3 - panicking::default_handler::hf1209fec3f963ae7H0z
   4:     0x7f5effce642c - sys_common::unwind::begin_unwind_inner::h2ff9ae045f111c6dg2t
   5:     0x7f5effce7e18 - sys_common::unwind::begin_unwind_fmt::hf803f209d02109a7m1t
   6:     0x7f5effd11b41 - rust_begin_unwind
   7:     0x7f5effd67dcf - panicking::panic_fmt::hd76b622b6f659cc5FRL
   8:     0x7f5effd688c8 - panicking::panic::h129376b8b435084ecQL
   9:     0x7f5efd0ca0ef - middle::traits::specialize::specialization_graph::Graph::parent::hb9009024a9897d1dGj0
  10:     0x7f5efd0ca417 - middle::traits::specialize::specialization_graph::Ancestors<'a, 'tcx>.Iterator::next::hd3a6140c01e72556Bp0
  11:     0x7f5efd0ca625 - iter::FlatMap<I, U, F>.Iterator::next::h9753486813069850975
  12:     0x7f5efd09f39e - middle::traits::project::assoc_ty_def::h2d4f59bcecc64af2TMV
  13:     0x7f5efd09aed1 - middle::traits::project::opt_normalize_projection_type::hac249e56767be130BSU
  14:     0x7f5efd087356 - middle::traits::project::normalize_projection_type::h5c927accb52af237qRU
  15:     0x7f5efcfc46fb - middle::traits::project::AssociatedTypeNormalizer<'a, 'b, 'tcx>.TypeFolder<'tcx>::fold_ty::h023fb72f91feb19c7OU
  16:     0x7f5efd0713a4 - middle::ty::fold::TypeFolder::fold_substs::h10129062906695728485
  17:     0x7f5efd070f54 - middle::ty::structural_impls::ty..Predicate<'tcx>.TypeFoldable<'tcx>::super_fold_with::h4768509243608403928
  18:     0x7f5efd0c33d3 - middle::traits::project::AssociatedTypeNormalizer<'a, 'b, 'tcx>::fold::h10624123112796617822
  19:     0x7f5efd0c2ff3 - middle::traits::select::SelectionContext<'cx, 'tcx>::impl_or_trait_obligations::_$u7b$$u7b$closure$u7d$$u7d$::closure.94592
  20:     0x7f5efd0c209e - iter::FlatMap<I, U, F>.Iterator::next::h5918725067989719148
  21:     0x7f5efd0c1193 - vec::Vec<T>.FromIterator<T>::from_iter::h2085870500798478170
  22:     0x7f5efd0bbce6 - middle::traits::select::SelectionContext<'cx, 'tcx>::impl_or_trait_obligations::hcef76fba84501e368YZ
  23:     0x7f5efd0bc605 - middle::traits::select::SelectionContext<'cx, 'tcx>::vtable_impl::hf052d7fa9a358527TjZ
  24:     0x7f5efd0bc285 - middle::infer::InferCtxt<'a, 'tcx>::commit_if_ok::h15771757354457876063
  25:     0x7f5efd0aae91 - middle::traits::select::SelectionContext<'cx, 'tcx>::confirm_candidate::h7f158130408656ecyRY
  26:     0x7f5efd0b09ae - middle::traits::select::SelectionContext<'cx, 'tcx>::evaluate_candidate::_$u7b$$u7b$closure$u7d$$u7d$::closure.94169
  27:     0x7f5efd0b060e - middle::traits::select::SelectionContext<'cx, 'tcx>::evaluate_stack::h863c364f8a43eda6ScX
  28:     0x7f5efd0af87b - middle::traits::select::SelectionContext<'cx, 'tcx>::evaluate_predicate_recursively::h68d69a192e1c5bfd53W
  29:     0x7f5efcfbf338 - middle::traits::type_known_to_meet_builtin_bound::he3b7e0685e8c00affg2
  30:     0x7f5efd0f3681 - middle::ty::util::ty..TyS<'tcx>::impls_bound::h72a76c819f3e2092Ww8
  31:     0x7f5efcfbf71f - middle::ty::util::ty..TyS<'tcx>::moves_by_default::he8454c3fc9f2398fdz8
  32:     0x7f5efcf16a8c - middle::infer::InferCtxt<'a, 'tcx>::type_moves_by_default::h328546648f89d696u3D
  33:     0x7f5efd0f0b04 - middle::ty::util::ParameterEnvironment<'a, 'tcx>::can_type_implement_copy::h3770fa101b94d348O57
  34:     0x7f5eff10ba52 - coherence::CoherenceChecker<'a, 'tcx>::check_implementations_of_copy::_$u7b$$u7b$closure$u7d$$u7d$::closure.47302
  35:     0x7f5eff00c83c - coherence::check_coherence::h4b13e71c9c2e25ffqeB
  36:     0x7f5eff0056e8 - check_crate::hf1eeac8d4e98098a6KC
  37:     0x7f5f0024366c - driver::phase_3_run_analysis_passes::_$u7b$$u7b$closure$u7d$$u7d$::closure.30392
  38:     0x7f5f00241c64 - middle::ty::context::TyCtxt<'tcx>::create_and_enter::h9147142471428683876
  39:     0x7f5f0023e842 - driver::phase_3_run_analysis_passes::h401012091542974636
  40:     0x7f5f0021103f - driver::compile_input::h5061645098a52196Pca
  41:     0x7f5f001fe90c - run_compiler::hf1a385ebc338137cJPc
  42:     0x7f5f001fbf91 - sys_common::unwind::try::try_fn::h13370330027690439195
  43:     0x7f5effd11acb - __rust_try
  44:     0x7f5effd11a5d - sys_common::unwind::inner_try::h87a6865a03ff0831iZt
  45:     0x7f5f001fc7da - boxed::F.FnBox<A>::call_box::h11886714385289713998
  46:     0x7f5effd1c549 - sys::thread::Thread::new::thread_start::haca995caeb3b74699Xy
  47:     0x7f5ef83f8669 - start_thread
  48:     0x7f5eff99001c - clone
  49:                0x0 - <unknown>

[alexcrichton]

cc @aturon, looks like a regression from stable:

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', ../src/libcore/option.rs:330
stack backtrace:
   1:     0x7f413757f240 - sys::backtrace::tracing::imp::write::h3bbb320d569781f92cv
   2:     0x7f413758943f - panicking::default_handler::_$u7b$$u7b$closure$u7d$$u7d$::closure.44520
   3:     0x7f4137588fb3 - panicking::default_handler::hf1209fec3f963ae7H0z
   4:     0x7f413755142c - sys_common::unwind::begin_unwind_inner::h2ff9ae045f111c6dg2t
   5:     0x7f4137552e18 - sys_common::unwind::begin_unwind_fmt::hf803f209d02109a7m1t
   6:     0x7f413757cb41 - rust_begin_unwind
   7:     0x7f41375d2dcf - panicking::panic_fmt::hd76b622b6f659cc5FRL
   8:     0x7f41375d38c8 - panicking::panic::h129376b8b435084ecQL
   9:     0x7f413493456f - middle::traits::specialize::specialization_graph::Graph::parent::h886c310fe93a88f1Ti0
  10:     0x7f4134934897 - middle::traits::specialize::specialization_graph::Ancestors<'a, 'tcx>.Iterator::next::h5f1f8c8250ab34dbOo0
  11:     0x7f4134934aa5 - iter::FlatMap<I, U, F>.Iterator::next::h12062584353781924757
  12:     0x7f41349095ae - middle::traits::project::assoc_ty_def::h5d120741f44a11c06LV
  13:     0x7f41349050e1 - middle::traits::project::opt_normalize_projection_type::h36d3a11130067195ORU
  14:     0x7f41348f1566 - middle::traits::project::normalize_projection_type::h92bf646187f6dba6DQU
  15:     0x7f413482f56b - middle::traits::project::AssociatedTypeNormalizer<'a, 'b, 'tcx>.TypeFolder<'tcx>::fold_ty::h3e59de177ca5ef75kOU
  16:     0x7f41348db5b4 - middle::ty::fold::TypeFolder::fold_substs::h17488734294738903057
  17:     0x7f41348db164 - middle::ty::structural_impls::ty..Predicate<'tcx>.TypeFoldable<'tcx>::super_fold_with::h7573436449953994461
  18:     0x7f413492d853 - middle::traits::project::AssociatedTypeNormalizer<'a, 'b, 'tcx>::fold::h13602687418497751053
  19:     0x7f413492d473 - middle::traits::select::SelectionContext<'cx, 'tcx>::impl_or_trait_obligations::_$u7b$$u7b$closure$u7d$$u7d$::closure.94585
  20:     0x7f413492c51e - iter::FlatMap<I, U, F>.Iterator::next::h325336949154668876
  21:     0x7f413492b613 - vec::Vec<T>.FromIterator<T>::from_iter::h5234805169717341186
  22:     0x7f4134926156 - middle::traits::select::SelectionContext<'cx, 'tcx>::impl_or_trait_obligations::h066c3f9f1f5e12a2lYZ
  23:     0x7f4134926a75 - middle::traits::select::SelectionContext<'cx, 'tcx>::vtable_impl::h0dd41e2ec59f0b116iZ
  24:     0x7f41349266f5 - middle::infer::InferCtxt<'a, 'tcx>::commit_if_ok::h16395859049726102179
  25:     0x7f41349150a1 - middle::traits::select::SelectionContext<'cx, 'tcx>::confirm_candidate::h64b3b64f12dac6e0LQY
  26:     0x7f413491abbe - middle::traits::select::SelectionContext<'cx, 'tcx>::evaluate_candidate::_$u7b$$u7b$closure$u7d$$u7d$::closure.94162
  27:     0x7f413491a81e - middle::traits::select::SelectionContext<'cx, 'tcx>::evaluate_stack::h525d267d7df64b2b5bX
  28:     0x7f4134919a8b - middle::traits::select::SelectionContext<'cx, 'tcx>::evaluate_predicate_recursively::hc18edfbb929b1024i3W
  29:     0x7f413482a1a8 - middle::traits::type_known_to_meet_builtin_bound::h559f2f377672bde3sf2
  30:     0x7f413495db01 - middle::ty::util::ty..TyS<'tcx>::impls_bound::hea825de3b49d4af69v8
  31:     0x7f413482a58f - middle::ty::util::ty..TyS<'tcx>::moves_by_default::h7508f4e507ba4fabqy8
  32:     0x7f4134781abc - middle::infer::InferCtxt<'a, 'tcx>::type_moves_by_default::h46ffa30aa912310fu3D
  33:     0x7f413495af84 - middle::ty::util::ParameterEnvironment<'a, 'tcx>::can_type_implement_copy::h368bfd5da63957a9147
  34:     0x7f413697a222 - coherence::CoherenceChecker<'a, 'tcx>::check_implementations_of_copy::_$u7b$$u7b$closure$u7d$$u7d$::closure.47300
  35:     0x7f413687a8ec - coherence::check_coherence::h4b13e71c9c2e25ffqeB
  36:     0x7f4136873798 - check_crate::h77c69415d924c1d56KC
  37:     0x7f4137aaf5ec - driver::phase_3_run_analysis_passes::_$u7b$$u7b$closure$u7d$$u7d$::closure.30392
  38:     0x7f4137aadbe4 - middle::ty::context::TyCtxt<'tcx>::create_and_enter::h11491607379472695545
  39:     0x7f4137aaa7c2 - driver::phase_3_run_analysis_passes::h6358585460292857359
  40:     0x7f4137a7cfbf - driver::compile_input::haf40356f083c88b6Pca
  41:     0x7f4137a6a88c - run_compiler::hb6d95af7384b3b47JPc
  42:     0x7f4137a67f11 - sys_common::unwind::try::try_fn::h18012394097158299251
  43:     0x7f413757cacb - __rust_try
  44:     0x7f413757ca5d - sys_common::unwind::inner_try::h87a6865a03ff0831iZt
  45:     0x7f4137a6875a - boxed::F.FnBox<A>::call_box::h17291146252477097894
  46:     0x7f4137587549 - sys::thread::Thread::new::thread_start::haca995caeb3b74699Xy
  47:     0x7f412fc62181 - start_thread
  48:     0x7f41371f347c - __clone
  49:                0x0 - <unknown>

[alexcrichton]

creduce managed to minimize this to at least just a small target trait (maybe gfx_core doesn't need to be minimized?)

extern crate gfx_core;                                              

#[derive(Copy)]                                                     
enum Command {                                                      
    BindConstantBuffers(gfx_core::pso::ConstantBufferSet<Resources>)
}                                                                   

enum Resources { }                                                  

impl gfx_core::Resources for Resources {}                           

[alexcrichton]

triage: I-nominated

[sanxiyn]

Single file reduction:

trait Resources {
    type Buffer;
}

#[derive(Copy)]
struct ConstantBufferSet<R: Resources>(
    pub R::Buffer
);

enum It {}
impl Resources for It {}

#[derive(Copy)]
enum Command {
    BindConstantBuffers(ConstantBufferSet<It>)
}

[olsonjeffery]

🙏