thread 'rustc' panicked at compiler/rustc_middle/src/ty/sty.rs:363:36: called `Option::unwrap()` on a `None` value

[KaliTheCatgirl]

Hi,

While making a reverse-engineering framework, I seem to have found an issue with the incomplete generic_const_exprs feature, as there appears to be a conflict with traits.

This ICE does not happen for usages within the same crate; merging lib.rs into main.rs will successfully compile.

Code

lib.rs:

#![allow(incomplete_features)]
#![feature(generic_const_exprs)]

pub trait TestTrait {
    const SIZE: usize;
    fn test_fn(bytes: [u8; Self::SIZE]);
}
pub struct TestStruct<const N: usize>;
impl<const N: usize> TestTrait for TestStruct<N> {
    const SIZE: usize = N;
    fn test_fn(_: [u8; Self::SIZE]) {}
}

main.rs:

use ice_test::TestTrait;

fn main() {
    ice_test::TestStruct::<12>::test_fn([0; 12]);
}

Meta

rustc --version --verbose:

rustc 1.85.0-nightly (d10a6823f 2024-11-29)
binary: rustc
commit-hash: d10a6823f4c3176be7a05a2454e5c33b861cb05f
commit-date: 2024-11-29
host: x86_64-unknown-linux-gnu
release: 1.85.0-nightly
LLVM version: 19.1.4

Error output

error: could not compile `ice_test` (bin "ice_test")

Caused by:
  process didn't exit successfully: `/home/kali/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustc --crate-name ice_test --edition=2021 src/main.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=175 --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 --check-cfg 'cfg(docsrs)' --check-cfg 'cfg(feature, values())' -C metadata=3593e76aa8f5c164 -C extra-filename=-3593e76aa8f5c164 --out-dir /media/kali/Big/girlcode/rs/ice_test/target/debug/deps -C incremental=/media/kali/Big/girlcode/rs/ice_test/target/debug/incremental -L dependency=/media/kali/Big/girlcode/rs/ice_test/target/debug/deps --extern ice_test=/media/kali/Big/girlcode/rs/ice_test/target/debug/deps/libice_test-bafdc74fa4e6a076.rlib` (exit status: 101)

Backtrace

   Compiling ice_test v0.1.0 (/media/kali/Big/girlcode/rs/ice_test)
thread 'rustc' panicked at compiler/rustc_middle/src/ty/sty.rs:363:36:
called `Option::unwrap()` on a `None` value
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::panic
   3: core::option::unwrap_failed
   4: <rustc_middle::ty::sty::ParamConst>::find_ty_from_env.cold
   5: <rustc_trait_selection::traits::fulfill::FulfillProcessor as rustc_data_structures::obligation_forest::ObligationProcessor>::process_obligation
   6: <rustc_data_structures::obligation_forest::ObligationForest<rustc_trait_selection::traits::fulfill::PendingPredicateObligation>>::process_obligations::<rustc_trait_selection::traits::fulfill::FulfillProcessor>
   7: rustc_traits::codegen::codegen_select_candidate
      [... omitted 3 frames ...]
   8: rustc_ty_utils::instance::resolve_instance_raw
      [... omitted 1 frame ...]
   9: <rustc_middle::ty::context::TyCtxt>::const_eval_resolve
  10: <rustc_const_eval::interpret::eval_context::InterpCx<rustc_const_eval::const_eval::machine::CompileTimeMachine>>::push_stack_frame_raw
  11: rustc_const_eval::const_eval::eval_queries::eval_to_allocation_raw_provider
      [... omitted 3 frames ...]
  12: rustc_const_eval::const_eval::valtrees::eval_to_valtree
  13: <rustc_const_eval::provide::{closure#0} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_middle::ty::PseudoCanonicalInput<rustc_middle::mir::interpret::GlobalId>)>>::call_once
      [... omitted 3 frames ...]
  14: rustc_middle::query::plumbing::query_get_at::<rustc_query_system::query::caches::DefaultCache<rustc_middle::ty::PseudoCanonicalInput<rustc_middle::mir::interpret::GlobalId>, rustc_middle::query::erase::Erased<[u8; 24]>>>
  15: <rustc_middle::ty::context::TyCtxt>::const_eval_global_id_for_typeck
  16: <rustc_middle::ty::context::TyCtxt>::const_eval_resolve_for_typeck
  17: rustc_trait_selection::traits::try_evaluate_const
  18: rustc_trait_selection::traits::evaluate_const
  19: <rustc_trait_selection::traits::normalize_param_env_or_error::{closure#0}::ConstNormalizer as rustc_type_ir::fold::TypeFolder<rustc_middle::ty::context::TyCtxt>>::fold_const
  20: rustc_trait_selection::traits::normalize_param_env_or_error
  21: rustc_ty_utils::ty::param_env
      [... omitted 1 frame ...]
  22: rustc_ty_utils::abi::fn_abi_of_instance
      [... omitted 1 frame ...]
  23: rustc_monomorphize::mono_checks::check_mono_item
      [... omitted 1 frame ...]
  24: rustc_monomorphize::collector::items_of_instance
      [... omitted 1 frame ...]
  25: rustc_monomorphize::collector::collect_items_rec::{closure#0}
  26: rustc_monomorphize::collector::collect_items_rec
  27: rustc_monomorphize::collector::collect_items_rec
  28: rustc_monomorphize::partitioning::collect_and_partition_mono_items
      [... omitted 2 frames ...]
  29: <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_ssa::traits::backend::CodegenBackend>::codegen_crate
  30: <rustc_interface::queries::Linker>::codegen_and_build_linker
  31: rustc_interface::interface::run_compiler::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

error: the compiler unexpectedly panicked. this is a bug.

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: please attach the file at `/media/kali/Big/girlcode/rs/ice_test/rustc-ice-2024-11-30T19_19_35-1189533.txt` to your bug report

note: compiler flags: --crate-type bin -C embed-bitcode=no -C debuginfo=2 -C incremental=[REDACTED]

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

query stack during panic:
#0 [codegen_select_candidate] computing candidate for `<ice_test::TestStruct<N> as ice_test::TestTrait>`
#1 [resolve_instance_raw] resolving instance `<ice_test::TestStruct<N> as ice_test::TestTrait>::SIZE`
#2 [eval_to_allocation_raw] const-evaluating + checking `<ice_test::TestStruct<N> as ice_test::TestTrait>::test_fn::{constant#0}`
#3 [eval_to_valtree] evaluating type-level constant
#4 [param_env] computing normalized predicates of `<ice_test::TestStruct<N> as ice_test::TestTrait>::test_fn`
#5 [fn_abi_of_instance] computing call ABI of `<ice_test::TestStruct<12> as ice_test::TestTrait>::test_fn`
#6 [check_mono_item] monomorphization-time checking
#7 [items_of_instance] collecting items used by `<ice_test::TestStruct<12> as ice_test::TestTrait>::test_fn`
#8 [collect_and_partition_mono_items] collect_and_partition_mono_items
end of query stack
error: could not compile `ice_test` (bin "ice_test")

Caused by:
  process didn't exit successfully: `/home/kali/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustc --crate-name ice_test --edition=2021 src/main.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=175 --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 --check-cfg 'cfg(docsrs)' --check-cfg 'cfg(feature, values())' -C metadata=3593e76aa8f5c164 -C extra-filename=-3593e76aa8f5c164 --out-dir /media/kali/Big/girlcode/rs/ice_test/target/debug/deps -C incremental=/media/kali/Big/girlcode/rs/ice_test/target/debug/incremental -L dependency=/media/kali/Big/girlcode/rs/ice_test/target/debug/deps --extern ice_test=/media/kali/Big/girlcode/rs/ice_test/target/debug/deps/libice_test-bafdc74fa4e6a076.rlib` (exit status: 101)

rustc-ice-2024-11-30T19_19_35-1189533.txt

[cyrgani]

Looks like the same as #131054 and #128525.

[workingjubilee]

seems correct, closing as duplicate.