ICE: `failed to resolve instance for ErrorGuaranteed()`

[matthiaskrgr]

auto-reduced (treereduce-rust):

#![feature(const_trait_impl, effects, const_closures)]

trait Bar {
    fn foo(&self);
}

impl Bar for () {}

const Branch: () = {
    (const || (&() as &dyn Bar).foo())();
};

original:

#![feature(const_trait_impl, effects, const_closures)]

#[derive(Eq, PartialEq)]
trait Bar {
    fn foo(&self);
}

impl Bar for () {
    type R = U;
}

const Branch: () = {
    (const || (&() as &dyn Bar).foo())();
};

Version information

rustc 1.81.0-nightly (16b569057 2024-07-16)
binary: rustc
commit-hash: 16b569057e4d1591b4bee05f10df34000308dedc
commit-date: 2024-07-16
host: x86_64-unknown-linux-gnu
release: 1.81.0-nightly
LLVM version: 18.1.7

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc

Program output

warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
 --> /tmp/icemaker_global_tempdir.Yy3tFb0ckOY1/rustc_testrunner_tmpdir_reporting.zpJOe0CdlMnS/mvce.rs:1:30
  |
1 | #![feature(const_trait_impl, effects, const_closures)]
  |                              ^^^^^^^
  |
  = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
  = note: `#[warn(incomplete_features)]` on by default

warning: the feature `const_closures` is incomplete and may not be safe to use and/or cause compiler crashes
 --> /tmp/icemaker_global_tempdir.Yy3tFb0ckOY1/rustc_testrunner_tmpdir_reporting.zpJOe0CdlMnS/mvce.rs:1:39
  |
1 | #![feature(const_trait_impl, effects, const_closures)]
  |                                       ^^^^^^^^^^^^^^
  |
  = note: see issue #106003 <https://github.com/rust-lang/rust/issues/106003> for more information

error[E0601]: `main` function not found in crate `mvce`
  --> /tmp/icemaker_global_tempdir.Yy3tFb0ckOY1/rustc_testrunner_tmpdir_reporting.zpJOe0CdlMnS/mvce.rs:11:3
   |
11 | };
   |   ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.Yy3tFb0ckOY1/rustc_testrunner_tmpdir_reporting.zpJOe0CdlMnS/mvce.rs`

error: using `#![feature(effects)]` without enabling next trait solver globally
  |
  = note: the next trait solver must be enabled globally for the effects feature to work correctly
  = help: use `-Znext-solver` to enable

error[E0046]: not all trait items implemented, missing: `foo`
 --> /tmp/icemaker_global_tempdir.Yy3tFb0ckOY1/rustc_testrunner_tmpdir_reporting.zpJOe0CdlMnS/mvce.rs:7:1
  |
4 |     fn foo(&self);
  |     -------------- `foo` from trait
...
7 | impl Bar for () {}
  | ^^^^^^^^^^^^^^^ missing `foo` in implementation

error: internal compiler error: compiler/rustc_middle/src/ty/instance.rs:605:25: failed to resolve instance for <() as Bar>::foo: Err(
                                    ErrorGuaranteed(
                                        (),
                                    ),
                                )
 --> /tmp/icemaker_global_tempdir.Yy3tFb0ckOY1/rustc_testrunner_tmpdir_reporting.zpJOe0CdlMnS/mvce.rs:4:5
  |
4 |     fn foo(&self);
  |     ^^^^^^^^^^^^^^

thread 'rustc' panicked at compiler/rustc_middle/src/ty/instance.rs:605:25:
Box<dyn Any>
stack backtrace:
   0:     0x78373547f3e5 - std::backtrace_rs::backtrace::libunwind::trace::hfb477357653a4e4f
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/../../backtrace/src/backtrace/libunwind.rs:116:5
   1:     0x78373547f3e5 - std::backtrace_rs::backtrace::trace_unsynchronized::h525c0fd0df716fa6
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x78373547f3e5 - std::sys::backtrace::_print_fmt::ha838f41c5e535f51
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/sys/backtrace.rs:65:5
   3:     0x78373547f3e5 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h1e9b6837be55babe
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/sys/backtrace.rs:40:26
   4:     0x7837354cee1b - core::fmt::rt::Argument::fmt::h964c89d0f98e9825
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/core/src/fmt/rt.rs:173:76
   5:     0x7837354cee1b - core::fmt::write::h806b4533fac49ea3
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/core/src/fmt/mod.rs:1182:21
   6:     0x783735473e9f - std::io::Write::write_fmt::h63c0ff199204c41f
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/io/mod.rs:1827:15
   7:     0x783735481bd1 - std::sys::backtrace::BacktraceLock::print::h64a586f07964a880
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/sys/backtrace.rs:43:9
   8:     0x783735481bd1 - std::panicking::default_hook::{{closure}}::h027d3d88677b9c45
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/panicking.rs:269:22
   9:     0x7837354818ac - std::panicking::default_hook::hb3342887544240f4
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/panicking.rs:296:9
  10:     0x7837317fab3a - std[e26dd15980711d9]::panicking::update_hook::<alloc[4a4297c918417764]::boxed::Box<rustc_driver_impl[c14dc3c35b3af881]::install_ice_hook::{closure#0}>>::{closure#0}
  11:     0x78373548259f - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h40fc715dd10a461f
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/alloc/src/boxed.rs:2084:9
  12:     0x78373548259f - std::panicking::rust_panic_with_hook::hb25aeb72f7ce42c5
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/panicking.rs:808:13
  13:     0x783731835ab1 - std[e26dd15980711d9]::panicking::begin_panic::<rustc_errors[c28d6f5ecad04e0f]::ExplicitBug>::{closure#0}
  14:     0x783731828a66 - std[e26dd15980711d9]::sys::backtrace::__rust_end_short_backtrace::<std[e26dd15980711d9]::panicking::begin_panic<rustc_errors[c28d6f5ecad04e0f]::ExplicitBug>::{closure#0}, !>
  15:     0x783731823d36 - std[e26dd15980711d9]::panicking::begin_panic::<rustc_errors[c28d6f5ecad04e0f]::ExplicitBug>
  16:     0x78373183f0f1 - <rustc_errors[c28d6f5ecad04e0f]::diagnostic::BugAbort as rustc_errors[c28d6f5ecad04e0f]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
  17:     0x783731db00fd - <rustc_errors[c28d6f5ecad04e0f]::DiagCtxtHandle>::span_bug::<rustc_span[145419c69115c40]::span_encoding::Span, alloc[4a4297c918417764]::string::String>
  18:     0x783731e4db68 - rustc_middle[37b79f53eb06cf87]::util::bug::opt_span_bug_fmt::<rustc_span[145419c69115c40]::span_encoding::Span>::{closure#0}
  19:     0x783731e33d4a - rustc_middle[37b79f53eb06cf87]::ty::context::tls::with_opt::<rustc_middle[37b79f53eb06cf87]::util::bug::opt_span_bug_fmt<rustc_span[145419c69115c40]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  20:     0x783731e33beb - rustc_middle[37b79f53eb06cf87]::ty::context::tls::with_context_opt::<rustc_middle[37b79f53eb06cf87]::ty::context::tls::with_opt<rustc_middle[37b79f53eb06cf87]::util::bug::opt_span_bug_fmt<rustc_span[145419c69115c40]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  21:     0x783731e4da97 - rustc_middle[37b79f53eb06cf87]::util::bug::span_bug_fmt::<rustc_span[145419c69115c40]::span_encoding::Span>
  22:     0x7837331745b9 - <rustc_middle[37b79f53eb06cf87]::ty::instance::Instance>::expect_resolve
  23:     0x783733206c72 - <rustc_middle[37b79f53eb06cf87]::ty::instance::Instance>::expect_resolve_for_vtable
  24:     0x78373381eb9e - rustc_trait_selection[ed3e3a96aaaeccc4]::traits::vtable::vtable_entries::{closure#0}
  25:     0x78373381d79f - rustc_trait_selection[ed3e3a96aaaeccc4]::traits::vtable::vtable_entries
  26:     0x78373381d128 - rustc_query_impl[3483f987c0d12bd8]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[3483f987c0d12bd8]::query_impl::vtable_entries::dynamic_query::{closure#2}::{closure#0}, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 16usize]>>
  27:     0x78373381d0e7 - <rustc_query_impl[3483f987c0d12bd8]::query_impl::vtable_entries::dynamic_query::{closure#2} as core[3c089f87181ffccd]::ops::function::FnOnce<(rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt, rustc_type_ir[5352cd0572541382]::binder::Binder<rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt, rustc_type_ir[5352cd0572541382]::predicate::TraitRef<rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt>>)>>::call_once
  28:     0x783733b91e77 - rustc_query_system[24d50461402a49d7]::query::plumbing::try_execute_query::<rustc_query_impl[3483f987c0d12bd8]::DynamicConfig<rustc_query_system[24d50461402a49d7]::query::caches::DefaultCache<rustc_type_ir[5352cd0572541382]::binder::Binder<rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt, rustc_type_ir[5352cd0572541382]::predicate::TraitRef<rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt>>, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[3483f987c0d12bd8]::plumbing::QueryCtxt, false>
  29:     0x783733b91bb9 - rustc_query_impl[3483f987c0d12bd8]::query_impl::vtable_entries::get_query_non_incr::__rust_end_short_backtrace
  30:     0x78373176a706 - rustc_middle[37b79f53eb06cf87]::query::plumbing::query_get_at::<rustc_query_system[24d50461402a49d7]::query::caches::DefaultCache<rustc_type_ir[5352cd0572541382]::binder::Binder<rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt, rustc_type_ir[5352cd0572541382]::predicate::TraitRef<rustc_middle[37b79f53eb06cf87]::ty::context::TyCtxt>>, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 16usize]>>>
  31:     0x783733933d29 - <rustc_const_eval[93ad04c5b7bd53c7]::interpret::eval_context::InterpCx<rustc_const_eval[93ad04c5b7bd53c7]::const_eval::machine::CompileTimeMachine>>::eval_fn_call
  32:     0x7837339dfb01 - rustc_const_eval[93ad04c5b7bd53c7]::const_eval::eval_queries::eval_to_allocation_raw_provider
  33:     0x7837339ddab6 - rustc_query_impl[3483f987c0d12bd8]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[3483f987c0d12bd8]::query_impl::eval_to_allocation_raw::dynamic_query::{closure#2}::{closure#0}, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 24usize]>>
  34:     0x7837339d9751 - rustc_query_system[24d50461402a49d7]::query::plumbing::try_execute_query::<rustc_query_impl[3483f987c0d12bd8]::DynamicConfig<rustc_query_system[24d50461402a49d7]::query::caches::DefaultCache<rustc_middle[37b79f53eb06cf87]::ty::ParamEnvAnd<rustc_middle[37b79f53eb06cf87]::mir::interpret::GlobalId>, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[3483f987c0d12bd8]::plumbing::QueryCtxt, false>
  35:     0x7837339d9330 - rustc_query_impl[3483f987c0d12bd8]::query_impl::eval_to_allocation_raw::get_query_non_incr::__rust_end_short_backtrace
  36:     0x7837339daaaa - rustc_const_eval[93ad04c5b7bd53c7]::const_eval::eval_queries::eval_to_const_value_raw_provider
  37:     0x7837339da8b6 - rustc_query_impl[3483f987c0d12bd8]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[3483f987c0d12bd8]::query_impl::eval_to_const_value_raw::dynamic_query::{closure#2}::{closure#0}, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 24usize]>>
  38:     0x7837339d9714 - rustc_query_system[24d50461402a49d7]::query::plumbing::try_execute_query::<rustc_query_impl[3483f987c0d12bd8]::DynamicConfig<rustc_query_system[24d50461402a49d7]::query::caches::DefaultCache<rustc_middle[37b79f53eb06cf87]::ty::ParamEnvAnd<rustc_middle[37b79f53eb06cf87]::mir::interpret::GlobalId>, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[3483f987c0d12bd8]::plumbing::QueryCtxt, false>
  39:     0x7837339d9236 - rustc_query_impl[3483f987c0d12bd8]::query_impl::eval_to_const_value_raw::get_query_non_incr::__rust_end_short_backtrace
  40:     0x7837330582b6 - <rustc_middle[37b79f53eb06cf87]::hir::map::Map>::par_body_owners::<rustc_hir_analysis[2f70e26aa6aa2212]::check_crate::{closure#3}>::{closure#0}
  41:     0x783733055a54 - rustc_hir_analysis[2f70e26aa6aa2212]::check_crate
  42:     0x783733208455 - rustc_interface[8230c53daf47eda8]::passes::analysis
  43:     0x78373320800d - rustc_query_impl[3483f987c0d12bd8]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[3483f987c0d12bd8]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 1usize]>>
  44:     0x783733cef5a5 - rustc_query_system[24d50461402a49d7]::query::plumbing::try_execute_query::<rustc_query_impl[3483f987c0d12bd8]::DynamicConfig<rustc_query_system[24d50461402a49d7]::query::caches::SingleCache<rustc_middle[37b79f53eb06cf87]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[3483f987c0d12bd8]::plumbing::QueryCtxt, false>
  45:     0x783733cef30f - rustc_query_impl[3483f987c0d12bd8]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  46:     0x783733bde045 - rustc_interface[8230c53daf47eda8]::interface::run_compiler::<core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>, rustc_driver_impl[c14dc3c35b3af881]::run_compiler::{closure#0}>::{closure#1}
  47:     0x783733bbcfc9 - std[e26dd15980711d9]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[8230c53daf47eda8]::util::run_in_thread_with_globals<rustc_interface[8230c53daf47eda8]::util::run_in_thread_pool_with_globals<rustc_interface[8230c53daf47eda8]::interface::run_compiler<core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>, rustc_driver_impl[c14dc3c35b3af881]::run_compiler::{closure#0}>::{closure#1}, core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>>::{closure#0}, core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>>
  48:     0x783733bbcd7a - <<std[e26dd15980711d9]::thread::Builder>::spawn_unchecked_<rustc_interface[8230c53daf47eda8]::util::run_in_thread_with_globals<rustc_interface[8230c53daf47eda8]::util::run_in_thread_pool_with_globals<rustc_interface[8230c53daf47eda8]::interface::run_compiler<core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>, rustc_driver_impl[c14dc3c35b3af881]::run_compiler::{closure#0}>::{closure#1}, core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>>::{closure#0}, core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3c089f87181ffccd]::result::Result<(), rustc_span[145419c69115c40]::ErrorGuaranteed>>::{closure#2} as core[3c089f87181ffccd]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  49:     0x78373548c5fb - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h442e913a0171ae2e
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/alloc/src/boxed.rs:2070:9
  50:     0x78373548c5fb - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hfda8e09c8c96ddbb
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/alloc/src/boxed.rs:2070:9
  51:     0x78373548c5fb - std::sys::pal::unix::thread::Thread::new::thread_start::h2322d98845956ea2
                               at /rustc/16b569057e4d1591b4bee05f10df34000308dedc/library/std/src/sys/pal/unix/thread.rs:108:17
  52:     0x783735220ded - <unknown>
  53:     0x7837352a40dc - <unknown>
  54:                0x0 - <unknown>

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: please make sure that you have updated to the latest nightly

note: rustc 1.81.0-nightly (16b569057 2024-07-16) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [vtable_entries] finding all vtable entries for trait `Bar`
#1 [eval_to_allocation_raw] const-evaluating + checking `Branch`
end of query stack
error: aborting due to 4 previous errors; 2 warnings emitted

Some errors have detailed explanations: E0046, E0601.
For more information about an error, try `rustc --explain E0046`.

@rustbot label +F-const_trait_impl +F-effects +F-const_closures

[GrigorenkoPV]

Regression in #121087

[fmease]

Effects is no more and the implementation of const_trait_impl has changed dramatically. This is obviously fixed. I don't think it's worth adding a regression test. If you disagree, feel free to open a PR and ping [@]rust-lang/project-const-traits for a "majority vote".