Repository: rust
Issue: ICE: `!base.layout().is_sized()`
Labels: I-ICE,T-compiler,C-bug,A-const-eval,-Zpolymorphize,S-bug-has-test

<!--
[31mICE[0m: Rustc ./a.rs '-Zdump-mir=all -Zpolymorphize=on -ooutputfile -Zdump-mir-dir=dir' 'thread 'rustc' panicked at compiler/rustc_const_eval/src/interpret/projection.rs:158:13: 'assertion failed: !base.layout().is_sized()'', 'thread 'rustc' panicked at compiler/rustc_const_eval/src/interpret/projection.rs:158:13: 'assertion failed: !base.layout().is_sized()''
File: /tmp/im/a.rs
-->

auto-reduced (treereduce-rust):
````rust
pub trait TraitCat {}
pub trait TraitDog {}

pub fn gamma<T: TraitCat + TraitDog>(t: [TraitDog; 32]) {}


````

original:
````rust
pub struct P;
pub struct R<T>(T);
pub struct R<T>(T);

// in_args test
pub fn alef() -> &'static [R<P>] { T {} }
pub fn epsilon(_x: [R<Q>; 32]) -> R<[Q; 32]> { loop {} }

// in_args test
pub fn alpha(_x: R<&'static [T; 32]>) { loop { loop {} } }
pub fn beta(_x: [T<Q>; 32]) { loop {} }

pub trait TraitCat {}
pub trait TraitDog {}

pub fn gamma<T: TraitCat + TraitDog>(t: [TraitDog; 32]) {}

pub fn beta<T: TraitCat + TraitDog>(t: &[Q]) {}

````

Version information
````
rustc 1.79.0-nightly (261823eee 2024-04-27)
binary: rustc
commit-hash: 261823eee7021ae24e282e2ca28dbbd3d287b10f
commit-date: 2024-04-27
host: x86_64-unknown-linux-gnu
release: 1.79.0-nightly
LLVM version: 18.1.4

````

Command:
`/home/matthias/.rustup/toolchains/master/bin/rustc -Zdump-mir=all -Zpolymorphize=on`

<!--
Include a backtrace in the code block by setting `RUST_BACKTRACE=1` in your
environment. E.g. `RUST_BACKTRACE=1 cargo build`.
-->
<details><summary><strong>Program output</strong></summary>
<p>

```
error[E0601]: `main` function not found in crate `mvce`
 --> /tmp/icemaker_global_tempdir.XYBMwHRwxebv/rustc_testrunner_tmpdir_reporting.AsHkdl3OtxCh/mvce.rs:4:59
  |
4 | pub fn gamma<T: TraitCat + TraitDog>(t: [TraitDog; 32]) {}
  |                                                           ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.XYBMwHRwxebv/rustc_testrunner_tmpdir_reporting.AsHkdl3OtxCh/mvce.rs`

warning: trait objects without an explicit `dyn` are deprecated
 --> /tmp/icemaker_global_tempdir.XYBMwHRwxebv/rustc_testrunner_tmpdir_reporting.AsHkdl3OtxCh/mvce.rs:4:42
  |
4 | pub fn gamma<T: TraitCat + TraitDog>(t: [TraitDog; 32]) {}
  |                                          ^^^^^^^^
  |
  = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
  = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
  = note: `#[warn(bare_trait_objects)]` on by default
help: if this is an object-safe trait, use `dyn`
  |
4 | pub fn gamma<T: TraitCat + TraitDog>(t: [dyn TraitDog; 32]) {}
  |                                          +++

error[E0277]: the size for values of type `(dyn TraitDog + 'static)` cannot be known at compilation time
 --> /tmp/icemaker_global_tempdir.XYBMwHRwxebv/rustc_testrunner_tmpdir_reporting.AsHkdl3OtxCh/mvce.rs:4:41
  |
4 | pub fn gamma<T: TraitCat + TraitDog>(t: [TraitDog; 32]) {}
  |                                         ^^^^^^^^^^^^^^ doesn't have a size known at compile-time
  |
  = help: the trait `Sized` is not implemented for `(dyn TraitDog + 'static)`
  = note: slice and array elements must have `Sized` type

warning: unused variable: `t`
 --> /tmp/icemaker_global_tempdir.XYBMwHRwxebv/rustc_testrunner_tmpdir_reporting.AsHkdl3OtxCh/mvce.rs:4:38
  |
4 | pub fn gamma<T: TraitCat + TraitDog>(t: [TraitDog; 32]) {}
  |                                      ^ help: if this is intentional, prefix it with an underscore: `_t`
  |
  = note: `#[warn(unused_variables)]` on by default

thread 'rustc' panicked at compiler/rustc_const_eval/src/interpret/projection.rs:158:13:
assertion failed: !base.layout().is_sized()
stack backtrace:
   0:     0x7cd1f314f015 - std::backtrace_rs::backtrace::libunwind::trace::hb7074df2638d7e84
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/../../backtrace/src/backtrace/libunwind.rs:105:5
   1:     0x7cd1f314f015 - std::backtrace_rs::backtrace::trace_unsynchronized::h70e69390b8223c7c
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7cd1f314f015 - std::sys_common::backtrace::_print_fmt::hfe37e9d78e7e5435
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7cd1f314f015 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::he8d68a3925434bb5
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7cd1f319e27b - core::fmt::rt::Argument::fmt::h2eb91a7d978fdcfd
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/rt.rs:165:63
   5:     0x7cd1f319e27b - core::fmt::write::h861d74bf08a00cf3
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:1157:21
   6:     0x7cd1f3143bbf - std::io::Write::write_fmt::h85f35fafd21dc258
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/io/mod.rs:1832:15
   7:     0x7cd1f314edee - std::sys_common::backtrace::_print::he8e1fa34d894fbed
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7cd1f314edee - std::sys_common::backtrace::print::h2307b89917ed7766
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7cd1f3151759 - std::panicking::default_hook::{{closure}}::h867d00d7ce9f86ae
  10:     0x7cd1f315149d - std::panicking::default_hook::h5c7e7badcca734ef
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/panicking.rs:298:9
  11:     0x7cd1efa33f6c - std[569c2c2086c9894c]::panicking::update_hook::<alloc[60db01e4fabc4ed5]::boxed::Box<rustc_driver_impl[c1bc4f62c0e337ce]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7cd1f3151e56 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h033bf5b8a4e39f67
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/alloc/src/boxed.rs:2036:9
  13:     0x7cd1f3151e56 - std::panicking::rust_panic_with_hook::h8af2337d7fada5ef
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/panicking.rs:799:13
  14:     0x7cd1f3151bcb - std::panicking::begin_panic_handler::{{closure}}::h9dd247a94cb9a353
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/panicking.rs:656:13
  15:     0x7cd1f314f4d9 - std::sys_common::backtrace::__rust_end_short_backtrace::h8203b00c60fbdb39
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7cd1f3151937 - rust_begin_unwind
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/panicking.rs:652:5
  17:     0x7cd1f319a743 - core::panicking::panic_fmt::h35f546a8bd23ea6e
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/panicking.rs:72:14
  18:     0x7cd1f319a7ec - core::panicking::panic::h44ebe4dfd40269d2
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/panicking.rs:146:5
  19:     0x7cd1f0e88e00 - <rustc_const_eval[e00bb822f5368508]::interpret::eval_context::InterpCx<rustc_const_eval[e00bb822f5368508]::const_eval::machine::CompileTimeInterpreter>>::project_field::<rustc_const_eval[e00bb822f5368508]::interpret::operand::OpTy>
  20:     0x7cd1ef9b608e - <core[3150d8b50ee94ec]::iter::adapters::GenericShunt<core[3150d8b50ee94ec]::iter::adapters::map::Map<core[3150d8b50ee94ec]::ops::range::Range<usize>, rustc_const_eval[e00bb822f5368508]::const_eval::try_destructure_mir_constant_for_user_output::{closure#0}>, core[3150d8b50ee94ec]::option::Option<core[3150d8b50ee94ec]::convert::Infallible>> as core[3150d8b50ee94ec]::iter::traits::iterator::Iterator>::next
  21:     0x7cd1efa06755 - rustc_const_eval[e00bb822f5368508]::const_eval::try_destructure_mir_constant_for_user_output
  22:     0x7cd1efee4d0f - rustc_middle[6a3e410634ca3b5d]::mir::pretty::pretty_print_const_value_tcx
  23:     0x7cd1efed00f9 - <rustc_middle[6a3e410634ca3b5d]::mir::consts::Const as core[3150d8b50ee94ec]::fmt::Display>::fmt
  24:     0x7cd1f319e27b - core::fmt::rt::Argument::fmt::h2eb91a7d978fdcfd
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/rt.rs:165:63
  25:     0x7cd1f319e27b - core::fmt::write::h861d74bf08a00cf3
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:1157:21
  26:     0x7cd1efee89c3 - <rustc_middle[6a3e410634ca3b5d]::mir::VarDebugInfoContents as core[3150d8b50ee94ec]::fmt::Debug>::fmt
  27:     0x7cd1f319e27b - core::fmt::rt::Argument::fmt::h2eb91a7d978fdcfd
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/rt.rs:165:63
  28:     0x7cd1f319e27b - core::fmt::write::h861d74bf08a00cf3
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:1157:21
  29:     0x7cd1efedaf4d - <rustc_middle[6a3e410634ca3b5d]::mir::VarDebugInfo as core[3150d8b50ee94ec]::fmt::Debug>::fmt
  30:     0x7cd1f319e20d - core::fmt::rt::Argument::fmt::h2eb91a7d978fdcfd
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/rt.rs:165:63
  31:     0x7cd1f319e20d - core::fmt::run::hd23c2dc20ef8fca9
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:1207:14
  32:     0x7cd1f319e20d - core::fmt::write::h861d74bf08a00cf3
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:1174:26
  33:     0x7cd1f318e9ab - <&mut W as core::fmt::Write::write_fmt::SpecWriteFmt>::spec_write_fmt::h5b27e4b035fafa5e
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:218:21
  34:     0x7cd1f318e9ab - core::fmt::Write::write_fmt::he542c0aa2d6aa4f9
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/core/src/fmt/mod.rs:223:9
  35:     0x7cd1f318e9ab - alloc::fmt::format::format_inner::h76fdbe8077b86deb
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/alloc/src/fmt.rs:633:16
  36:     0x7cd1efed9b48 - rustc_middle[6a3e410634ca3b5d]::mir::pretty::write_scope_tree
  37:     0x7cd1efedb6a6 - rustc_middle[6a3e410634ca3b5d]::mir::pretty::write_mir_intro
  38:     0x7cd1f003c1c7 - rustc_middle[6a3e410634ca3b5d]::mir::pretty::write_mir_fn::<rustc_mir_transform[341d6274d6eed658]::pass_manager::dump_mir_for_phase_change::{closure#0}>
  39:     0x7cd1f0e027e2 - rustc_mir_transform[341d6274d6eed658]::pass_manager::run_passes_inner
  40:     0x7cd1f160f640 - rustc_mir_transform[341d6274d6eed658]::optimized_mir
  41:     0x7cd1f160e82b - rustc_query_impl[8b44e8a7f8d883bf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[8b44e8a7f8d883bf]::query_impl::optimized_mir::dynamic_query::{closure#2}::{closure#0}, rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 8usize]>>
  42:     0x7cd1f0e9228e - rustc_query_system[cb6ba9990df42599]::query::plumbing::try_execute_query::<rustc_query_impl[8b44e8a7f8d883bf]::DynamicConfig<rustc_query_system[cb6ba9990df42599]::query::caches::DefIdCache<rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[8b44e8a7f8d883bf]::plumbing::QueryCtxt, false>
  43:     0x7cd1f0e919e6 - rustc_query_impl[8b44e8a7f8d883bf]::query_impl::optimized_mir::get_query_non_incr::__rust_end_short_backtrace
  44:     0x7cd1f1108c56 - rustc_middle[6a3e410634ca3b5d]::query::plumbing::query_get_at::<rustc_query_system[cb6ba9990df42599]::query::caches::DefIdCache<rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 8usize]>>>
  45:     0x7cd1f11232d2 - rustc_query_impl[8b44e8a7f8d883bf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[8b44e8a7f8d883bf]::query_impl::unused_generic_params::dynamic_query::{closure#2}::{closure#0}, rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 4usize]>>
  46:     0x7cd1f1122a99 - rustc_query_system[cb6ba9990df42599]::query::plumbing::try_execute_query::<rustc_query_impl[8b44e8a7f8d883bf]::DynamicConfig<rustc_query_system[cb6ba9990df42599]::query::caches::DefaultCache<rustc_middle[6a3e410634ca3b5d]::ty::instance::InstanceDef, rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 4usize]>>, false, false, false>, rustc_query_impl[8b44e8a7f8d883bf]::plumbing::QueryCtxt, false>
  47:     0x7cd1f112278e - rustc_query_impl[8b44e8a7f8d883bf]::query_impl::unused_generic_params::get_query_non_incr::__rust_end_short_backtrace
  48:     0x7cd1f111eee6 - rustc_interface[a6e61e277917f284]::passes::analysis
  49:     0x7cd1f111dbd5 - rustc_query_impl[8b44e8a7f8d883bf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[8b44e8a7f8d883bf]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 1usize]>>
  50:     0x7cd1f1bc6665 - rustc_query_system[cb6ba9990df42599]::query::plumbing::try_execute_query::<rustc_query_impl[8b44e8a7f8d883bf]::DynamicConfig<rustc_query_system[cb6ba9990df42599]::query::caches::SingleCache<rustc_middle[6a3e410634ca3b5d]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[8b44e8a7f8d883bf]::plumbing::QueryCtxt, false>
  51:     0x7cd1f1bc63c9 - rustc_query_impl[8b44e8a7f8d883bf]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  52:     0x7cd1f1a4648e - rustc_interface[a6e61e277917f284]::interface::run_compiler::<core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>, rustc_driver_impl[c1bc4f62c0e337ce]::run_compiler::{closure#0}>::{closure#1}
  53:     0x7cd1f1a34467 - std[569c2c2086c9894c]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[a6e61e277917f284]::util::run_in_thread_with_globals<rustc_interface[a6e61e277917f284]::util::run_in_thread_pool_with_globals<rustc_interface[a6e61e277917f284]::interface::run_compiler<core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>, rustc_driver_impl[c1bc4f62c0e337ce]::run_compiler::{closure#0}>::{closure#1}, core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>>::{closure#0}, core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>>
  54:     0x7cd1f1a3422a - <<std[569c2c2086c9894c]::thread::Builder>::spawn_unchecked_<rustc_interface[a6e61e277917f284]::util::run_in_thread_with_globals<rustc_interface[a6e61e277917f284]::util::run_in_thread_pool_with_globals<rustc_interface[a6e61e277917f284]::interface::run_compiler<core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>, rustc_driver_impl[c1bc4f62c0e337ce]::run_compiler::{closure#0}>::{closure#1}, core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>>::{closure#0}, core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3150d8b50ee94ec]::result::Result<(), rustc_span[6f362a2079b27969]::ErrorGuaranteed>>::{closure#2} as core[3150d8b50ee94ec]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  55:     0x7cd1f315bc8b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hec05d78b62dc2056
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/alloc/src/boxed.rs:2022:9
  56:     0x7cd1f315bc8b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h3bd70c017b255ecd
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/alloc/src/boxed.rs:2022:9
  57:     0x7cd1f315bc8b - std::sys::pal::unix::thread::Thread::new::thread_start::haab106638cc78137
                               at /rustc/261823eee7021ae24e282e2ca28dbbd3d287b10f/library/std/src/sys/pal/unix/thread.rs:108:17
  58:     0x7cd1ec8a955a - <unknown>
  59:     0x7cd1ec926a3c - <unknown>
  60:                0x0 - <unknown>

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: rustc 1.79.0-nightly (261823eee 2024-04-27) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z dump-mir=all -Z polymorphize=on -Z dump-mir-dir=dir

query stack during panic:
#0 [optimized_mir] optimizing MIR for `gamma`
#1 [unused_generic_params] determining which generic parameters are unused by `gamma`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 2 previous errors; 2 warnings emitted

Some errors have detailed explanations: E0277, E0601.
For more information about an error, try `rustc --explain E0277`.

```

</p>
</details>

<!--
query stack:
#0 [optimized_mir] optimizing MIR for `gamma`
#1 [unused_generic_params] determining which generic parameters are unused by `gamma`
#2 [analysis] running analysis passes on this crate

-->