ICE: bx.cx().is_backend_scalar_pair(cast): dyn star

[matthiaskrgr]

Code

./src/test/ui/dyn-star/dont-unsize-coerce-dyn-star.rs

// check-pass

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

trait AddOne {
    fn add1(&mut self) -> usize;
}

impl AddOne for usize {
    fn add1(&mut self) -> usize {
        *self += 1;
        *self
    }
}

fn add_one(i: &mut (dyn* AddOne + '_)) -> usize {
    i.add1()
}

fn main() {
    let mut x = 42usize as dyn* AddOne;

    println!("{}", add_one(&mut x));
    println!("{}", add_one(&mut x));
}

Meta

rustc --version --verbose:

rustc 1.67.0-nightly (ff8c8dfbe 2022-11-22)
binary: rustc
commit-hash: ff8c8dfbe66701531e3e5e335c28c544d0fbc945
commit-date: 2022-11-22
host: x86_64-unknown-linux-gnu
release: 1.67.0-nightly
LLVM version: 15.0.4

Error output

<output>

Backtrace

thread '<unnamed>' panicked at 'assertion failed: bx.cx().is_backend_scalar_pair(cast)', /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/compiler/rustc_codegen_ssa/src/mir/rvalue.rs:227:25
stack backtrace:
   0:     0x7f3aa9966240 - std::backtrace_rs::backtrace::libunwind::trace::h8706adb1093146ed
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f3aa9966240 - std::backtrace_rs::backtrace::trace_unsynchronized::hf63de70ab53f1103
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f3aa9966240 - std::sys_common::backtrace::_print_fmt::h5957d298699ffe59
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7f3aa9966240 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hcd957416de719678
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f3aa99c865e - core::fmt::write::h984028dcea06bcfd
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/core/src/fmt/mod.rs:1208:17
   5:     0x7f3aa99566c5 - std::io::Write::write_fmt::he809968620ea8258
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/io/mod.rs:1682:15
   6:     0x7f3aa9966005 - std::sys_common::backtrace::_print::hb0bd3686578e8d46
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/sys_common/backtrace.rs:47:5
   7:     0x7f3aa9966005 - std::sys_common::backtrace::print::hc5833b565793a292
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/sys_common/backtrace.rs:34:9
   8:     0x7f3aa9968d0f - std::panicking::default_hook::{{closure}}::h74c2f33bce600c62
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/panicking.rs:267:22
   9:     0x7f3aa9968a4a - std::panicking::default_hook::hfe2fefb386033115
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/panicking.rs:286:9
  10:     0x7f3aa996951c - std::panicking::rust_panic_with_hook::he2509c58eec530df
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/panicking.rs:688:13
  11:     0x7f3aa9969271 - std::panicking::begin_panic_handler::{{closure}}::h119207ccf961ce41
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/panicking.rs:577:13
  12:     0x7f3aa99666ec - std::sys_common::backtrace::__rust_end_short_backtrace::hcaa5a71abba4373d
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/sys_common/backtrace.rs:137:18
  13:     0x7f3aa9968fd2 - rust_begin_unwind
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/panicking.rs:575:5
  14:     0x7f3aa99c5033 - core::panicking::panic_fmt::hfba047ce4c50c7c1
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/core/src/panicking.rs:65:14
  15:     0x7f3aa99c510d - core::panicking::panic::h1d3088ee0ec67c87
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/core/src/panicking.rs:114:5
  16:     0x7f3aab17b14f - <rustc_codegen_ssa[e8308c49eae86124]::mir::FunctionCx<rustc_codegen_llvm[a7c379c6fc230ce8]::builder::Builder>>::codegen_block
  17:     0x7f3aab167134 - rustc_codegen_ssa[e8308c49eae86124]::mir::codegen_mir::<rustc_codegen_llvm[a7c379c6fc230ce8]::builder::Builder>
  18:     0x7f3aab65f529 - rustc_codegen_llvm[a7c379c6fc230ce8]::base::compile_codegen_unit::module_codegen
  19:     0x7f3aac2d0313 - <rustc_query_system[5a7ebb5f2835af36]::dep_graph::graph::DepGraph<rustc_middle[10860b0b9ad25f4]::dep_graph::dep_node::DepKind>>::with_task::<rustc_middle[10860b0b9ad25f4]::ty::context::TyCtxt, rustc_span[452fb2538b9e8b2]::symbol::Symbol, rustc_codegen_ssa[e8308c49eae86124]::ModuleCodegen<rustc_codegen_llvm[a7c379c6fc230ce8]::ModuleLlvm>>
  20:     0x7f3aac2d002a - rustc_codegen_llvm[a7c379c6fc230ce8]::base::compile_codegen_unit
  21:     0x7f3aac2eb47b - rustc_codegen_ssa[e8308c49eae86124]::base::codegen_crate::<rustc_codegen_llvm[a7c379c6fc230ce8]::LlvmCodegenBackend>
  22:     0x7f3aac2eac39 - <rustc_codegen_llvm[a7c379c6fc230ce8]::LlvmCodegenBackend as rustc_codegen_ssa[e8308c49eae86124]::traits::backend::CodegenBackend>::codegen_crate
  23:     0x7f3aabee7fc1 - <rustc_session[60eb0f9dbaf3963]::session::Session>::time::<alloc[9f61cdb96537af8e]::boxed::Box<dyn core[f8fd3abe6b5d63cf]::any::Any>, rustc_interface[6b7eaaa4ad5b511f]::passes::start_codegen::{closure#0}>
  24:     0x7f3aabee7ab4 - rustc_interface[6b7eaaa4ad5b511f]::passes::start_codegen
  25:     0x7f3aabee1e70 - <rustc_interface[6b7eaaa4ad5b511f]::passes::QueryContext>::enter::<<rustc_interface[6b7eaaa4ad5b511f]::queries::Queries>::ongoing_codegen::{closure#0}::{closure#0}, core[f8fd3abe6b5d63cf]::result::Result<alloc[9f61cdb96537af8e]::boxed::Box<dyn core[f8fd3abe6b5d63cf]::any::Any>, rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>
  26:     0x7f3aabedf273 - <rustc_interface[6b7eaaa4ad5b511f]::queries::Queries>::ongoing_codegen
  27:     0x7f3aabede382 - <rustc_interface[6b7eaaa4ad5b511f]::interface::Compiler>::enter::<rustc_driver[9074794128a33992]::run_compiler::{closure#1}::{closure#2}, core[f8fd3abe6b5d63cf]::result::Result<core[f8fd3abe6b5d63cf]::option::Option<rustc_interface[6b7eaaa4ad5b511f]::queries::Linker>, rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>
  28:     0x7f3aabed9382 - rustc_span[452fb2538b9e8b2]::with_source_map::<core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>, rustc_interface[6b7eaaa4ad5b511f]::interface::run_compiler<core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>, rustc_driver[9074794128a33992]::run_compiler::{closure#1}>::{closure#0}::{closure#1}>
  29:     0x7f3aabed8e79 - <scoped_tls[d8d79e187ce2c7fa]::ScopedKey<rustc_span[452fb2538b9e8b2]::SessionGlobals>>::set::<rustc_interface[6b7eaaa4ad5b511f]::interface::run_compiler<core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>, rustc_driver[9074794128a33992]::run_compiler::{closure#1}>::{closure#0}, core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>
  30:     0x7f3aabed8488 - std[1e9db942fc5862bc]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[6b7eaaa4ad5b511f]::util::run_in_thread_pool_with_globals<rustc_interface[6b7eaaa4ad5b511f]::interface::run_compiler<core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>, rustc_driver[9074794128a33992]::run_compiler::{closure#1}>::{closure#0}, core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>
  31:     0x7f3aabed81ac - <<std[1e9db942fc5862bc]::thread::Builder>::spawn_unchecked_<rustc_interface[6b7eaaa4ad5b511f]::util::run_in_thread_pool_with_globals<rustc_interface[6b7eaaa4ad5b511f]::interface::run_compiler<core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>, rustc_driver[9074794128a33992]::run_compiler::{closure#1}>::{closure#0}, core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[f8fd3abe6b5d63cf]::result::Result<(), rustc_errors[962da50c5f46999b]::ErrorGuaranteed>>::{closure#1} as core[f8fd3abe6b5d63cf]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  32:     0x7f3aad9ca733 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h1b5a13ff0dfa7f2f
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/alloc/src/boxed.rs:2000:9
  33:     0x7f3aad9ca733 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hba33c2ecbf5798cf
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/alloc/src/boxed.rs:2000:9
  34:     0x7f3aad9ca733 - std::sys::unix::thread::Thread::new::thread_start::hb6c57436b925359e
                               at /rustc/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/std/src/sys/unix/thread.rs:108:17
  35:     0x7f3aa96cd8fd - <unknown>
  36:     0x7f3aa974fa60 - <unknown>
  37:                0x0 - <unknown>

[compiler-errors]

Probably fixed by #104594, though I'll check later.