ICE adt_const_params with slice of static str

[meowjesty]

Looks a bit like #88384

Link to playground

Code

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

struct FooConst<const ARRAY: &'static [&'static str]> {}

const FOO_ARR: &[&'static str; 2] = &["Hello", "Friend"];

fn main() {
    // Commenting the following line avoids the panic.
    let foo = FooConst::<FOO_ARR> {};
}

Meta

rustc --version --verbose:

rustc 1.56.0-nightly (50171c310 2021-09-01) running on x86_64-unknown-linux-gnu
compiler flags: -C embed-bitcode=no -C codegen-units=1 -C debuginfo=2 --crate-type bin

rustc 1.57.0-nightly (b69fe5726 2021-09-10) running on x86_64-pc-windows-msvc
compiler flags: -C embed-bitcode=no -C debuginfo=2 -C incremental --crate-type lib

Error output

error: internal compiler error: compiler/rustc_mir/src/const_eval/mod.rs:160:14: cannot destructure constant Const { ty: &'static [&'static str], val: Value(ByRef { alloc: Allocation { bytes: [0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [(Size { raw: 0 }, alloc5)] }), init_mask: InitMask { blocks: [65535], len: Size { raw: 16 } }, align: Align { pow2: 3 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

Backtrace

Compiling playground v0.0.1 (/playground)
error: internal compiler error: compiler/rustc_mir/src/const_eval/mod.rs:160:14: cannot destructure constant Const { ty: &'static [&'static str], val: Value(ByRef { alloc: Allocation { bytes: [0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [(Size { raw: 0 }, alloc5)] }), init_mask: InitMask { blocks: [65535], len: Size { raw: 16 } }, align: Align { pow2: 3 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

thread 'rustc' panicked at 'Box<dyn Any>', compiler/rustc_errors/src/lib.rs:1147:9
stack backtrace:
   0: std::panicking::begin_panic
   1: std::panic::panic_any
   2: rustc_errors::HandlerInner::bug
   3: rustc_errors::Handler::bug
   4: rustc_middle::ty::context::tls::with_opt
   5: rustc_middle::util::bug::opt_span_bug_fmt
   6: rustc_middle::util::bug::bug_fmt
   7: rustc_mir::const_eval::destructure_const
   8: core::ops::function::FnOnce::call_once
   9: rustc_query_system::query::plumbing::get_query_impl
  10: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::destructure_const
  11: rustc_middle::ty::relate::super_relate_consts
  12: <rustc_infer::infer::combine::Generalizer as rustc_middle::ty::relate::TypeRelation>::consts
  13: <rustc_infer::infer::combine::Generalizer as rustc_middle::ty::relate::TypeRelation>::relate_with_variance
  14: <core::result::Result<T,E> as rustc_middle::ty::context::InternIteratorElement<T,R>>::intern_with
  15: <rustc_infer::infer::combine::Generalizer as rustc_middle::ty::relate::TypeRelation>::relate_item_substs
  16: rustc_middle::ty::relate::super_relate_tys
  17: <rustc_infer::infer::combine::Generalizer as rustc_middle::ty::relate::TypeRelation>::tys
  18: rustc_infer::infer::combine::CombineFields::instantiate
  19: <rustc_infer::infer::sub::Sub as rustc_middle::ty::relate::TypeRelation>::tys
  20: rustc_infer::infer::InferCtxt::commit_if_ok
  21: rustc_infer::infer::fudge::<impl rustc_infer::infer::InferCtxt>::fudge_inference_if_ok
  22: rustc_typeck::check::expr::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_expr_kind
  23: rustc_typeck::check::expr::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_expr_with_expectation
  24: rustc_typeck::check::fn_ctxt::checks::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_decl_initializer
  25: rustc_typeck::check::fn_ctxt::checks::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_decl_local
  26: rustc_typeck::check::fn_ctxt::checks::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_stmt
  27: rustc_typeck::check::fn_ctxt::checks::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_block_with_expected
  28: rustc_typeck::check::expr::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_expr_with_expectation
  29: rustc_typeck::check::expr::<impl rustc_typeck::check::fn_ctxt::FnCtxt>::check_return_expr
  30: rustc_typeck::check::check::check_fn
  31: rustc_infer::infer::InferCtxtBuilder::enter
  32: rustc_typeck::check::typeck
  33: rustc_query_system::query::plumbing::get_query_impl
  34: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::typeck
  35: rustc_middle::ty::<impl rustc_middle::ty::context::TyCtxt>::par_body_owners
  36: rustc_typeck::check::typeck_item_bodies
  37: rustc_query_system::query::plumbing::get_query_impl
  38: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::typeck_item_bodies
  39: rustc_session::utils::<impl rustc_session::session::Session>::time
  40: rustc_typeck::check_crate
  41: rustc_interface::passes::analysis
  42: rustc_query_system::query::plumbing::get_query_impl
  43: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::analysis
  44: rustc_interface::passes::QueryContext::enter
  45: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter
  46: rustc_span::with_source_map
  47: scoped_tls::ScopedKey<T>::set
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

note: 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: rustc 1.56.0-nightly (50171c310 2021-09-01) running on x86_64-unknown-linux-gnu

note: compiler flags: -C embed-bitcode=no -C codegen-units=1 -C debuginfo=2 --crate-type bin

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

query stack during panic:
#0 [destructure_const] destructure constant
#1 [typeck] type-checking `main`
#2 [typeck_item_bodies] type-checking all item bodies
#3 [analysis] running analysis passes on this crate
end of query stack
error: could not compile `playground`

[hellow554]

Used const_generics as feature and got this:

Regressed somewhere between f5d8117...36f1f04

Before

error[E0308]: mismatched types
  --> src/main.rs:10:15
   |
10 |     let foo = FooConst::<FOO_ARR> {};
   |               ^^^^^^^^^^^^^^^^^^^^^^ expected `FOO_ARR`, found `FOO_ARR`
   |
   = note: expected type `_`
            found struct `FooConst<FOO_ARR>`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0308`.
error: could not compile `abc`

After

error: internal compiler error: compiler/rustc_mir/src/const_eval/mod.rs:160:14: cannot destructure constant Const { ty: &'static [&'static str], val: Value(ByRef { alloc: Allocation { bytes: [0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [(Size { raw: 0 }, ((), alloc4))] }), init_mask: InitMask { blocks: [65535], len: Size { raw: 16 } }, size: Size { raw: 16 }, align: Align { pow2: 3 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

thread 'rustc' panicked at 'Box<Any>', /rustc/36f1f04f18b89ba4a999bcfd6584663fd6fc1c5d/library/std/src/panic.rs:59:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

note: 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: rustc 1.52.0-nightly (36f1f04f1 2021-03-17) running on x86_64-unknown-linux-gnu

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

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

query stack during panic:
#0 [destructure_const] destructure constant
#1 [typeck] type-checking `main`
end of query stack

[b-naber]

@rustbot claim