ice: dyn_star: unexpected TypeKind for left-hand side of dyn* cast: Void

[matthiaskrgr]

./tests/ui/dyn-star/dyn-star-to-dyn.rs

// run-pass

#![feature(dyn_star)]
//~^ WARN the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes

use std::fmt::Debug;

fn main() {
    let x: dyn* Debug = &42;
    let x = Box::new(x) as Box<dyn Debug>;
    assert_eq!("42", format!("{x:?}"));

    // Also test opposite direction.
    let x: Box<dyn Debug> = Box::new(42);
    let x = &x as dyn* Debug;
    assert_eq!("42", format!("{x:?}"));
}

warning: the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
 --> ./tests/ui/dyn-star/dyn-star-to-dyn.rs:3:12
  |
3 | #![feature(dyn_star)]
  |            ^^^^^^^^
  |
  = note: see issue #102425 <https://github.com/rust-lang/rust/issues/102425> for more information
  = note: `#[warn(incomplete_features)]` on by default

error: internal compiler error: /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/compiler/rustc_codegen_ssa/src/base.rs:279:17: unexpected TypeKind for left-hand side of `dyn*` cast: Void

thread 'rustc' panicked at 'Box<dyn Any>', /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/compiler/rustc_errors/src/lib.rs:1650:9
stack backtrace:
   0:     0x7f9bd3f67e11 - std::backtrace_rs::backtrace::libunwind::trace::h184786643c1f8146
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f9bd3f67e11 - std::backtrace_rs::backtrace::trace_unsynchronized::h10cef21dd42edd42
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f9bd3f67e11 - std::sys_common::backtrace::_print_fmt::hca8722c6f82eccd9
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7f9bd3f67e11 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h4b170c65cdf95c48
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f9bd3fc94bf - core::fmt::rt::Argument::fmt::h7e50834cab28e102
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/core/src/fmt/rt.rs:138:9
   5:     0x7f9bd3fc94bf - core::fmt::write::h8bd64fe81f89dd81
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/core/src/fmt/mod.rs:1094:21
   6:     0x7f9bd3f5a977 - std::io::Write::write_fmt::hc75a842b3ecac8bc
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/io/mod.rs:1714:15
   7:     0x7f9bd3f67c25 - std::sys_common::backtrace::_print::hdb7a31bd8c54eb49
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f9bd3f67c25 - std::sys_common::backtrace::print::hbcf968a4222dc0b5
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f9bd3f6a9d3 - std::panicking::default_hook::{{closure}}::h02987b13cfa1387d
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/panicking.rs:269:22
  10:     0x7f9bd3f6a764 - std::panicking::default_hook::hcb3fd44404995c49
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/panicking.rs:288:9
  11:     0x7f9bd71abd6b - <rustc_driver_impl[7175fdba515aac6e]::install_ice_hook::{closure#0} as core[baaa20f768102eef]::ops::function::FnOnce<(&core[baaa20f768102eef]::panic::panic_info::PanicInfo,)>>::call_once::{shim:vtable#0}
  12:     0x7f9bd3f6b1fe - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::hec1e31de726d1657
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/alloc/src/boxed.rs:2007:9
  13:     0x7f9bd3f6b1fe - std::panicking::rust_panic_with_hook::h223f39091438ac61
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/panicking.rs:709:13
  14:     0x7f9bd76ae8d1 - std[755122e38bdf80bb]::panicking::begin_panic::<rustc_errors[22c53a0383ffa2c9]::ExplicitBug>::{closure#0}
  15:     0x7f9bd76ad526 - std[755122e38bdf80bb]::sys_common::backtrace::__rust_end_short_backtrace::<std[755122e38bdf80bb]::panicking::begin_panic<rustc_errors[22c53a0383ffa2c9]::ExplicitBug>::{closure#0}, !>
  16:     0x7f9bd7742666 - std[755122e38bdf80bb]::panicking::begin_panic::<rustc_errors[22c53a0383ffa2c9]::ExplicitBug>
  17:     0x7f9bd76aa2e4 - <rustc_errors[22c53a0383ffa2c9]::HandlerInner>::bug::<alloc[d1ea88cdd25af2a4]::string::String>
  18:     0x7f9bd76aa166 - <rustc_errors[22c53a0383ffa2c9]::Handler>::bug::<alloc[d1ea88cdd25af2a4]::string::String>
  19:     0x7f9bd76fd5fc - rustc_middle[56c503886228b671]::util::bug::opt_span_bug_fmt::<rustc_span[1e0547ff349d1bca]::span_encoding::Span>::{closure#0}
  20:     0x7f9bd76fa49a - rustc_middle[56c503886228b671]::ty::context::tls::with_opt::<rustc_middle[56c503886228b671]::util::bug::opt_span_bug_fmt<rustc_span[1e0547ff349d1bca]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  21:     0x7f9bd76fa46a - rustc_middle[56c503886228b671]::ty::context::tls::with_context_opt::<rustc_middle[56c503886228b671]::ty::context::tls::with_opt<rustc_middle[56c503886228b671]::util::bug::opt_span_bug_fmt<rustc_span[1e0547ff349d1bca]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  22:     0x7f9bd54ef2bd - rustc_middle[56c503886228b671]::util::bug::bug_fmt
  23:     0x7f9bc9282ea5 - rustc_codegen_ssa::base::cast_to_dyn_star::hf2bda0974be9b1bf
  24:     0x7f9bc93a9d65 - rustc_codegen_ssa::mir::rvalue::<impl rustc_codegen_ssa::mir::FunctionCx<Bx>>::codegen_rvalue_operand::h1536923317528649
  25:     0x7f9bc939dbc4 - rustc_codegen_ssa::mir::codegen_mir::h3ad98a26028d240e
  26:     0x7f9bc9283015 - rustc_codegen_ssa::base::codegen_instance::h4de2a7fcd42b8fec
  27:     0x7f9bc92b779f - <rustc_middle::mir::mono::MonoItem as rustc_codegen_ssa::mono_item::MonoItemExt>::define::h3ba430a5d5241f22
  28:     0x7f9bc937aa8a - rustc_codegen_gcc::base::compile_codegen_unit::module_codegen::he6166c6882b2cbb7
  29:     0x7f9bc937999e - rustc_codegen_gcc::base::compile_codegen_unit::hee038d1e76e08ed1
  30:     0x7f9bc92a96fd - <rustc_codegen_gcc::GccCodegenBackend as rustc_codegen_ssa::traits::backend::ExtraBackendMethods>::compile_codegen_unit::h9454ef5ee5ef580e
  31:     0x7f9bc928276d - rustc_codegen_ssa::base::codegen_crate::h1a4124ddfd8d676d
  32:     0x7f9bc92a932a - <rustc_codegen_gcc::GccCodegenBackend as rustc_codegen_ssa::traits::backend::CodegenBackend>::codegen_crate::hfb6d3003355e12ad
  33:     0x7f9bd66dcbc2 - <rustc_session[ebb9057f9195e4cc]::session::Session>::time::<alloc[d1ea88cdd25af2a4]::boxed::Box<dyn core[baaa20f768102eef]::any::Any>, rustc_interface[e3841d12b9b221e7]::passes::start_codegen::{closure#0}>
  34:     0x7f9bd66dc73b - rustc_interface[e3841d12b9b221e7]::passes::start_codegen
  35:     0x7f9bd66d749d - <rustc_middle[56c503886228b671]::ty::context::GlobalCtxt>::enter::<<rustc_interface[e3841d12b9b221e7]::queries::Queries>::ongoing_codegen::{closure#0}::{closure#0}, core[baaa20f768102eef]::result::Result<alloc[d1ea88cdd25af2a4]::boxed::Box<dyn core[baaa20f768102eef]::any::Any>, rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>>
  36:     0x7f9bd66d66cd - <rustc_interface[e3841d12b9b221e7]::queries::Queries>::ongoing_codegen
  37:     0x7f9bd66d57f0 - <rustc_interface[e3841d12b9b221e7]::interface::Compiler>::enter::<rustc_driver_impl[7175fdba515aac6e]::run_compiler::{closure#1}::{closure#2}, core[baaa20f768102eef]::result::Result<core[baaa20f768102eef]::option::Option<rustc_interface[e3841d12b9b221e7]::queries::Linker>, rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>>
  38:     0x7f9bd66d2e21 - std[755122e38bdf80bb]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[e3841d12b9b221e7]::util::run_in_thread_pool_with_globals<rustc_interface[e3841d12b9b221e7]::interface::run_compiler<core[baaa20f768102eef]::result::Result<(), rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>, rustc_driver_impl[7175fdba515aac6e]::run_compiler::{closure#1}>::{closure#0}, core[baaa20f768102eef]::result::Result<(), rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[baaa20f768102eef]::result::Result<(), rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>>
  39:     0x7f9bd66d25a5 - <<std[755122e38bdf80bb]::thread::Builder>::spawn_unchecked_<rustc_interface[e3841d12b9b221e7]::util::run_in_thread_pool_with_globals<rustc_interface[e3841d12b9b221e7]::interface::run_compiler<core[baaa20f768102eef]::result::Result<(), rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>, rustc_driver_impl[7175fdba515aac6e]::run_compiler::{closure#1}>::{closure#0}, core[baaa20f768102eef]::result::Result<(), rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[baaa20f768102eef]::result::Result<(), rustc_span[1e0547ff349d1bca]::ErrorGuaranteed>>::{closure#1} as core[baaa20f768102eef]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  40:     0x7f9bd3f75685 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h59d6baf462325ed4
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/alloc/src/boxed.rs:1993:9
  41:     0x7f9bd3f75685 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h4eca0dd82537346f
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/alloc/src/boxed.rs:1993:9
  42:     0x7f9bd3f75685 - std::sys::unix::thread::Thread::new::thread_start::h38e13b8ca4256fdb
                               at /rustc/2d0aa57684e10f7b3d3fe740ee18d431181583ad/library/std/src/sys/unix/thread.rs:108:17
  43:     0x7f9bd3d0d44b - <unknown>
  44:     0x7f9bd3d90e40 - <unknown>
  45:                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: rustc 1.72.0-nightly (2d0aa5768 2023-06-18) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z codegen-backend=/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/target/release/librustc_codegen_gcc.so

query stack during panic:
end of query stack
error: aborting due to previous error; 1 warning emitted