ICE: `InstanceDef::Virtual (Virtual(DefId(..))) is for direct calls only` `lazy_type_alias` + mono items

[matthiaskrgr]

Code

rustc -Zprint-mono-items=eager file.rs

#![feature(lazy_type_alias)]

impl Trait for Struct {}
trait Trait {
    fn test(&self) {}
}

type Struct = dyn Trait + Send;

fn main() {}

Meta

rustc --version --verbose:

rustc 1.73.0-nightly (04abc370b 2023-07-28)
binary: rustc
commit-hash: 04abc370b9f3855b28172b65a7f7d5a433f41412
commit-date: 2023-07-28
host: x86_64-unknown-linux-gnu
release: 1.73.0-nightly
LLVM version: 16.0.5

Error output

...

Backtrace

error: internal compiler error: compiler/rustc_mir_transform/src/shim.rs:85:13: InstanceDef::Virtual (Virtual(DefId(0:5 ~ treereduce[f361]::Trait::test), 3)) is for direct calls only

thread 'rustc' panicked at 'Box<dyn Any>', /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/compiler/rustc_errors/src/lib.rs:1645:9
stack backtrace:
   0:     0x7f6500162fc1 - std::backtrace_rs::backtrace::libunwind::trace::hdb93c75af49465f7
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f6500162fc1 - std::backtrace_rs::backtrace::trace_unsynchronized::h173553974892ea20
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f6500162fc1 - std::sys_common::backtrace::_print_fmt::h4a408d1535f12ce7
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7f6500162fc1 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h80e339e782587177
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f65001c949c - core::fmt::rt::Argument::fmt::h48c77cd529068ea0
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/core/src/fmt/rt.rs:138:9
   5:     0x7f65001c949c - core::fmt::write::hd5614e3697ba0662
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/core/src/fmt/mod.rs:1094:21
   6:     0x7f65001555ce - std::io::Write::write_fmt::h18665f5cd588a024
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/io/mod.rs:1714:15
   7:     0x7f6500162dd5 - std::sys_common::backtrace::_print::h5415b7879e858e5a
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f6500162dd5 - std::sys_common::backtrace::print::hc72a2f092cb4fce1
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f6500165e2a - std::panicking::panic_hook_with_disk_dump::{{closure}}::h11ce7931c3e3ad73
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/panicking.rs:278:22
  10:     0x7f6500165ac3 - std::panicking::panic_hook_with_disk_dump::h32f84721a84edaa9
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/panicking.rs:312:9
  11:     0x7f650340ef39 - rustc_driver_impl[2d064f46b3c8d597]::install_ice_hook::{closure#0}
  12:     0x7f65001666d0 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h93009440feeb02eb
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/alloc/src/boxed.rs:2021:9
  13:     0x7f65001666d0 - std::panicking::rust_panic_with_hook::hc8970ff82cfba6ba
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/panicking.rs:733:13
  14:     0x7f65039ce591 - std[43ea1a6b17be2c75]::panicking::begin_panic::<rustc_errors[a4390c3b40f87867]::ExplicitBug>::{closure#0}
  15:     0x7f65039ce396 - std[43ea1a6b17be2c75]::sys_common::backtrace::__rust_end_short_backtrace::<std[43ea1a6b17be2c75]::panicking::begin_panic<rustc_errors[a4390c3b40f87867]::ExplicitBug>::{closure#0}, !>
  16:     0x7f650397c646 - std[43ea1a6b17be2c75]::panicking::begin_panic::<rustc_errors[a4390c3b40f87867]::ExplicitBug>
  17:     0x7f65039dd7a4 - <rustc_errors[a4390c3b40f87867]::HandlerInner>::bug::<alloc[98daf3ced61b4627]::string::String>
  18:     0x7f65039dd636 - <rustc_errors[a4390c3b40f87867]::Handler>::bug::<alloc[98daf3ced61b4627]::string::String>
  19:     0x7f65039b97cc - rustc_middle[dfa6d6dd80f6535c]::util::bug::opt_span_bug_fmt::<rustc_span[5d15a33e9175a7b0]::span_encoding::Span>::{closure#0}
  20:     0x7f65039b85ca - rustc_middle[dfa6d6dd80f6535c]::ty::context::tls::with_opt::<rustc_middle[dfa6d6dd80f6535c]::util::bug::opt_span_bug_fmt<rustc_span[5d15a33e9175a7b0]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  21:     0x7f65039b8598 - rustc_middle[dfa6d6dd80f6535c]::ty::context::tls::with_context_opt::<rustc_middle[dfa6d6dd80f6535c]::ty::context::tls::with_opt<rustc_middle[dfa6d6dd80f6535c]::util::bug::opt_span_bug_fmt<rustc_span[5d15a33e9175a7b0]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  22:     0x7f6501dd15e0 - rustc_middle[dfa6d6dd80f6535c]::util::bug::bug_fmt
  23:     0x7f65027a3dbd - rustc_mir_transform[ef19b90d23ceef0f]::shim::make_shim
  24:     0x7f650206388f - rustc_query_impl[9b7bf9fcc2c74b]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[9b7bf9fcc2c74b]::query_impl::mir_shims::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dfa6d6dd80f6535c]::query::erase::Erased<[u8; 8usize]>>
  25:     0x7f650206384c - <rustc_query_impl[9b7bf9fcc2c74b]::query_impl::mir_shims::dynamic_query::{closure#2} as core[b78222062286ce0]::ops::function::FnOnce<(rustc_middle[dfa6d6dd80f6535c]::ty::context::TyCtxt, rustc_middle[dfa6d6dd80f6535c]::ty::instance::InstanceDef)>>::call_once
  26:     0x7f6502065e70 - rustc_query_system[d8ac3be064c6a648]::query::plumbing::try_execute_query::<rustc_query_impl[9b7bf9fcc2c74b]::DynamicConfig<rustc_query_system[d8ac3be064c6a648]::query::caches::DefaultCache<rustc_middle[dfa6d6dd80f6535c]::ty::instance::InstanceDef, rustc_middle[dfa6d6dd80f6535c]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[9b7bf9fcc2c74b]::plumbing::QueryCtxt, false>
  27:     0x7f6502065b83 - rustc_query_impl[9b7bf9fcc2c74b]::query_impl::mir_shims::get_query_non_incr::__rust_end_short_backtrace
  28:     0x7f65018f7afc - <rustc_middle[dfa6d6dd80f6535c]::ty::context::TyCtxt>::instance_mir
  29:     0x7f6501478c46 - rustc_monomorphize[1ccdbbc078c7102a]::collector::collect_used_items
  30:     0x7f6501475615 - rustc_monomorphize[1ccdbbc078c7102a]::collector::collect_items_rec
  31:     0x7f65029c7d60 - rustc_data_structures[2f54d9eed481ad54]::sync::par_for_each_in::<alloc[98daf3ced61b4627]::vec::Vec<rustc_middle[dfa6d6dd80f6535c]::mir::mono::MonoItem>, rustc_monomorphize[1ccdbbc078c7102a]::collector::collect_crate_mono_items::{closure#1}::{closure#0}>
  32:     0x7f65029c7659 - <rustc_session[6dc82fd81d82b638]::session::Session>::time::<(), rustc_monomorphize[1ccdbbc078c7102a]::collector::collect_crate_mono_items::{closure#1}>
  33:     0x7f65029c72b8 - rustc_monomorphize[1ccdbbc078c7102a]::collector::collect_crate_mono_items
  34:     0x7f65029c5897 - rustc_monomorphize[1ccdbbc078c7102a]::partitioning::collect_and_partition_mono_items
  35:     0x7f6502a12c39 - rustc_query_impl[9b7bf9fcc2c74b]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[9b7bf9fcc2c74b]::query_impl::collect_and_partition_mono_items::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dfa6d6dd80f6535c]::query::erase::Erased<[u8; 24usize]>>
  36:     0x7f6502a12c0b - <rustc_query_impl[9b7bf9fcc2c74b]::query_impl::collect_and_partition_mono_items::dynamic_query::{closure#2} as core[b78222062286ce0]::ops::function::FnOnce<(rustc_middle[dfa6d6dd80f6535c]::ty::context::TyCtxt, ())>>::call_once
  37:     0x7f6502af881c - rustc_query_system[d8ac3be064c6a648]::query::plumbing::try_execute_query::<rustc_query_impl[9b7bf9fcc2c74b]::DynamicConfig<rustc_query_system[d8ac3be064c6a648]::query::caches::SingleCache<rustc_middle[dfa6d6dd80f6535c]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[9b7bf9fcc2c74b]::plumbing::QueryCtxt, false>
  38:     0x7f6502d85d48 - rustc_query_impl[9b7bf9fcc2c74b]::query_impl::collect_and_partition_mono_items::get_query_non_incr::__rust_end_short_backtrace
  39:     0x7f6502458c26 - rustc_codegen_ssa[7aa2eca03bf336cb]::base::codegen_crate::<rustc_codegen_llvm[7357bbc6bc95b1a0]::LlvmCodegenBackend>
  40:     0x7f6502458a0b - <rustc_codegen_llvm[7357bbc6bc95b1a0]::LlvmCodegenBackend as rustc_codegen_ssa[7aa2eca03bf336cb]::traits::backend::CodegenBackend>::codegen_crate
  41:     0x7f6502668762 - <rustc_session[6dc82fd81d82b638]::session::Session>::time::<alloc[98daf3ced61b4627]::boxed::Box<dyn core[b78222062286ce0]::any::Any>, rustc_interface[e815501e41232ae3]::passes::start_codegen::{closure#0}>
  42:     0x7f65026682db - rustc_interface[e815501e41232ae3]::passes::start_codegen
  43:     0x7f6502662f6a - <rustc_middle[dfa6d6dd80f6535c]::ty::context::GlobalCtxt>::enter::<<rustc_interface[e815501e41232ae3]::queries::Queries>::ongoing_codegen::{closure#0}, core[b78222062286ce0]::result::Result<alloc[98daf3ced61b4627]::boxed::Box<dyn core[b78222062286ce0]::any::Any>, rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>>
  44:     0x7f6502661fa3 - <rustc_interface[e815501e41232ae3]::interface::Compiler>::enter::<rustc_driver_impl[2d064f46b3c8d597]::run_compiler::{closure#1}::{closure#2}, core[b78222062286ce0]::result::Result<core[b78222062286ce0]::option::Option<rustc_interface[e815501e41232ae3]::queries::Linker>, rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>>
  45:     0x7f650265aff8 - std[43ea1a6b17be2c75]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[e815501e41232ae3]::util::run_in_thread_pool_with_globals<rustc_interface[e815501e41232ae3]::interface::run_compiler<core[b78222062286ce0]::result::Result<(), rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>, rustc_driver_impl[2d064f46b3c8d597]::run_compiler::{closure#1}>::{closure#0}, core[b78222062286ce0]::result::Result<(), rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[b78222062286ce0]::result::Result<(), rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>>
  46:     0x7f650265a77e - <<std[43ea1a6b17be2c75]::thread::Builder>::spawn_unchecked_<rustc_interface[e815501e41232ae3]::util::run_in_thread_pool_with_globals<rustc_interface[e815501e41232ae3]::interface::run_compiler<core[b78222062286ce0]::result::Result<(), rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>, rustc_driver_impl[2d064f46b3c8d597]::run_compiler::{closure#1}>::{closure#0}, core[b78222062286ce0]::result::Result<(), rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[b78222062286ce0]::result::Result<(), rustc_span[5d15a33e9175a7b0]::ErrorGuaranteed>>::{closure#1} as core[b78222062286ce0]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  47:     0x7f6500170dc5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h4f82faf6b02ba832
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/alloc/src/boxed.rs:2007:9
  48:     0x7f6500170dc5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hf73d60080ca8008e
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/alloc/src/boxed.rs:2007:9
  49:     0x7f6500170dc5 - std::sys::unix::thread::Thread::new::thread_start::hb438279e2a921916
                               at /rustc/04abc370b9f3855b28172b65a7f7d5a433f41412/library/std/src/sys/unix/thread.rs:108:17
  50:     0x7f64ffebf44b - <unknown>
  51:     0x7f64fff42e40 - <unknown>
  52:                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 attach the file at `/tmp/im/rustc-ice-2023-07-29T04:50:29.860118737Z-3547485.txt` to your bug report

note: compiler flags: -Z print-mono-items=eager

query stack during panic:
#0 [mir_shims] generating MIR shim for `Trait::test`
#1 [collect_and_partition_mono_items] collect_and_partition_mono_items
end of query stack
error: aborting due to previous error; 1 warning emitted

[matthiaskrgr]

Regression in nightly-2023-06-22
started with #112853 🤷

[fmease]

This doesn't need lazy type aliases to reproduce:

rustc -Zprint-mono-items=eager

impl Trait for <Ty as Owner>::Struct {}
trait Trait {
    fn test(&self) {}
}

enum Ty {}
trait Owner { type Struct: ?Sized; }
impl Owner for Ty {
    type Struct = dyn Trait + Send;
}

fn main() {}

[fmease]

I'd like to clarify, we should definitely keep the label F-lazy_type_alias since this code will regress if / once we make lazy type aliases the default (in a new edition). However, my finding demonstrates that the bug is preexisting. The faulty code path doesn't handle alias types (ty::AliasTy) correctly (ty::Projection in the case of associated types and ty::Weak in the case of lazy type aliases).