ICE: export stable: unreachable
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C-bug
F-export_stable
I-ICE
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S-has-bisection
S-has-mcve
T-compiler
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Description
auto-reduced (treereduce-rust):
#![crate_type = "sdylib"]
pub mod tys {
pub trait Trait {
type Type;
}
pub struct S;
#[export_stable]
pub extern "C" fn foo1(x: <S as Trait>::Type) -> u32 {
x.0
}
}
original code
original:
//@ compile-flags: -Zunstable-options -Csymbol-mangling-version=v0
#![crate_type = "sdylib"]
#![allow(incomplete_features, improper_ctypes_definitions)]
#![feature(export_stable)]
#![feature(inherent_associated_types)]
mod m {
#[export_stable]
pub struct S;
//~^ ERROR private items are not exportable
pub fn foo() -> i32 { 0 }
//~^ ERROR only functions with "C" ABI are exportable
}
#[export_stable]
pub use m::foo;
#[export_stable]
pub mod m1 {
#[repr(C)]
pub struct S1; // OK, public type with stable repr
struct S2;
pub struct S3;
//~^ ERROR types with unstable layout are not exportable
}
pub mod fn_sig {
#[export_stable]
pub fn foo1() {}
//~^ ERROR only functions with "C" ABI are exportable
#[export_stable]
#[repr(C)]
pub struct S;
#[export_stable]
pub extern "C" fn foo2(x: S) -> i32 { 0 }
#[export_stable]
pub extern "C" fn foo3(x: Box<S>) -> u32 { 0 }
//~^ ERROR function with `#[export_stable]` attribute uses type `Box<fn_sig::S>`, which is not exportable
}
pub mod impl_item {
pub struct S;
impl S {
#[export_stable]
pub extern "C" fn foo1(&self) -> i32 { 0 }
//~^ ERROR method with `#[export_stable]` attribute uses type `&impl_item::S`, which is not exportable
#[export_stable]
pub extern "C" fn foo2(self) -> i32 { 0 }
//~^ ERROR method with `#[export_stable]` attribute uses type `impl_item::S`, which is not exportable
}
pub struct S2<T>(T);
impl<T> S2<T> {
#[export_stable]
pub extern "C" fn foo1(&self) {}
//~^ ERROR generic functions are not exportable
}
}
pub mod tys {
pub trait Trait {
type Type;
}
pub struct S;
impl<T> S2<T> {
#[export_stable]
pub extern "C" fn foo1(_x: Type) {}
//~^ ERROR generic functions are not exportable
}
#[export_stable]
pub extern "C" fn foo1(x: <S as Trait>::Type) -> u32 { x.0 }
//~^ ERROR function with `#[export_stable]` attribute uses type `(u32,)`, which is not exportable
#[export_stable]
pub type Type = [i32; 4];
#[export_stable]
pub extern "C" fn foo2(_x: Type) {}
//~^ ERROR function with `#[export_stable]` attribute uses type `[i32; 4]`, which is not exportable
impl S {
#[export_stable]
pub type Type = extern "C" fn();
}
#[export_stable]
pub extern "C" fn foo3(_x: S::Type) {}
//~^ ERROR function with `#[export_stable]` attribute uses type `extern "C" fn()`, which is not exportable
#[export_stable]
pub extern "C" fn foo4() -> impl Copy {
//~^ ERROR function with `#[export_stable]` attribute uses type `impl Copy`, which is not exportable
0
}
}
pub mod privacy {
#[export_stable]
#[repr(C)]
pub struct S1 {
pub x: i32
}
#[export_stable]
#[repr(C)]
pub struct S2 {
//~^ ERROR ADT types with private fields are not exportable
x: i32
}
#[export_stable]
#[repr(i32)]
enum E {
//~^ ERROR private items are not exportable
Variant1 { x: i32 }
}
}
pub mod use_site {
#[export_stable]
pub trait Trait {}
//~^ ERROR trait's are not exportable
#[export_stable]
pub const C: i32 = 0;
//~^ ERROR constant's are not exportable
}
fn main() {}
Version information
rustc 1.88.0-nightly (4a0969e06 2025-05-05)
binary: rustc
commit-hash: 4a0969e06dbeaaa43914d2d00b2e843d49aa3886
commit-date: 2025-05-05
host: x86_64-unknown-linux-gnu
release: 1.88.0-nightly
LLVM version: 20.1.4
Possibly related line of code:
https://github.com/rust-lang/rust/blob/4a0969e06dbeaaa43914d2d00b2e843d49aa3886/compiler/rustc_passes/src/check_export.rs#L308-L320
Program output
error[E0658]: `sdylib` crate type is unstable
|
= note: see issue #139939 <https://github.com/rust-lang/rust/issues/139939> for more information
= help: add `#![feature(export_stable)]` to the crate attributes to enable
= note: this compiler was built on 2025-05-05; consider upgrading it if it is out of date
error[E0658]: the `#[export_stable]` attribute is an experimental feature
--> /tmp/icemaker_global_tempdir.byJkfAgCAC9o/rustc_testrunner_tmpdir_reporting.JiMazKFR2XRS/mvce.rs:9:5
|
9 | #[export_stable]
| ^^^^^^^^^^^^^^^^
|
= note: see issue #139939 <https://github.com/rust-lang/rust/issues/139939> for more information
= help: add `#![feature(export_stable)]` to the crate attributes to enable
= note: this compiler was built on 2025-05-05; consider upgrading it if it is out of date
thread 'rustc' panicked at compiler/rustc_passes/src/check_export.rs:314:82:
internal error: entered unreachable code
stack backtrace:
0: 0x7328f4119d43 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::hb403cd2fac0f6c35
1: 0x7328f48059c7 - core::fmt::write::h97f9b980855afdb0
2: 0x7328f5840951 - std::io::Write::write_fmt::hfe7060805776d40d
3: 0x7328f4119ba2 - std::sys::backtrace::BacktraceLock::print::hcaf5d44ed33dd540
4: 0x7328f411d9ea - std::panicking::default_hook::{{closure}}::hb71d08c73046b819
5: 0x7328f411d56f - std::panicking::default_hook::he64b7baf4c601acf
6: 0x7328f315dec3 - std[497b135e77342dfe]::panicking::update_hook::<alloc[5a025c98fe0abec9]::boxed::Box<rustc_driver_impl[93230f812dffb5e0]::install_ice_hook::{closure#1}>>::{closure#0}
7: 0x7328f411e263 - std::panicking::rust_panic_with_hook::h891e87933e43eb50
8: 0x7328f411df26 - std::panicking::begin_panic_handler::{{closure}}::h263154ab5bcd08b7
9: 0x7328f411a219 - std::sys::backtrace::__rust_end_short_backtrace::hb378e569ab779db4
10: 0x7328f411dc1d - __rustc[7c4bd70fde5450d7]::rust_begin_unwind
11: 0x7328f0a7d320 - core::panicking::panic_fmt::h00901a220ab693a7
12: 0x7328f0a8145c - core::panicking::panic::hea40ae5f747e880b
13: 0x7328f3ab6dd6 - <rustc_passes[41af3e947a78c530]::check_export::ExportableItemsChecker as rustc_type_ir[7a338a7a95dfce26]::visit::TypeVisitor<rustc_middle[dbca81a53272c93]::ty::context::TyCtxt>>::visit_ty
14: 0x7328f3ab663c - <rustc_passes[41af3e947a78c530]::check_export::ExportableItemsChecker>::check_nested_types_are_exportable
15: 0x7328f5629826 - rustc_passes[41af3e947a78c530]::check_export::exportable_items_provider_local
16: 0x7328f562a2f3 - rustc_query_impl[cdf8c0c3437f76cf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cdf8c0c3437f76cf]::query_impl::exportable_items::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbca81a53272c93]::query::erase::Erased<[u8; 16usize]>>
17: 0x7328f562a2c9 - <rustc_query_impl[cdf8c0c3437f76cf]::query_impl::exportable_items::dynamic_query::{closure#2} as core[e97d2bc10e1a68ca]::ops::function::FnOnce<(rustc_middle[dbca81a53272c93]::ty::context::TyCtxt, rustc_span[545b9213dc14cd2d]::def_id::CrateNum)>>::call_once
18: 0x7328f5626c4c - rustc_query_system[1fb475752ad60c19]::query::plumbing::try_execute_query::<rustc_query_impl[cdf8c0c3437f76cf]::DynamicConfig<rustc_data_structures[51b8745ee49836b]::vec_cache::VecCache<rustc_span[545b9213dc14cd2d]::def_id::CrateNum, rustc_middle[dbca81a53272c93]::query::erase::Erased<[u8; 16usize]>, rustc_query_system[1fb475752ad60c19]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[cdf8c0c3437f76cf]::plumbing::QueryCtxt, true>
19: 0x7328f562a996 - rustc_query_impl[cdf8c0c3437f76cf]::query_impl::exportable_items::get_query_incr::__rust_end_short_backtrace
20: 0x7328f4d3fb20 - rustc_interface[d8aa27404aa0decf]::passes::run_required_analyses
21: 0x7328f577d31e - rustc_interface[d8aa27404aa0decf]::passes::analysis
22: 0x7328f577d2f5 - rustc_query_impl[cdf8c0c3437f76cf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cdf8c0c3437f76cf]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbca81a53272c93]::query::erase::Erased<[u8; 0usize]>>
23: 0x7328f5777ec6 - rustc_query_system[1fb475752ad60c19]::query::plumbing::try_execute_query::<rustc_query_impl[cdf8c0c3437f76cf]::DynamicConfig<rustc_query_system[1fb475752ad60c19]::query::caches::SingleCache<rustc_middle[dbca81a53272c93]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[cdf8c0c3437f76cf]::plumbing::QueryCtxt, true>
24: 0x7328f57777e8 - rustc_query_impl[cdf8c0c3437f76cf]::query_impl::analysis::get_query_incr::__rust_end_short_backtrace
25: 0x7328f5a46807 - rustc_interface[d8aa27404aa0decf]::passes::create_and_enter_global_ctxt::<core[e97d2bc10e1a68ca]::option::Option<rustc_interface[d8aa27404aa0decf]::queries::Linker>, rustc_driver_impl[93230f812dffb5e0]::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}
26: 0x7328f587fca6 - rustc_interface[d8aa27404aa0decf]::interface::run_compiler::<(), rustc_driver_impl[93230f812dffb5e0]::run_compiler::{closure#0}>::{closure#1}
27: 0x7328f5837f3e - std[497b135e77342dfe]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[d8aa27404aa0decf]::util::run_in_thread_with_globals<rustc_interface[d8aa27404aa0decf]::util::run_in_thread_pool_with_globals<rustc_interface[d8aa27404aa0decf]::interface::run_compiler<(), rustc_driver_impl[93230f812dffb5e0]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
28: 0x7328f58383b4 - <<std[497b135e77342dfe]::thread::Builder>::spawn_unchecked_<rustc_interface[d8aa27404aa0decf]::util::run_in_thread_with_globals<rustc_interface[d8aa27404aa0decf]::util::run_in_thread_pool_with_globals<rustc_interface[d8aa27404aa0decf]::interface::run_compiler<(), rustc_driver_impl[93230f812dffb5e0]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[e97d2bc10e1a68ca]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
29: 0x7328f58397ab - std::sys::pal::unix::thread::Thread::new::thread_start::hac1b1fa51fe18dfe
30: 0x7328ef6a370a - <unknown>
31: 0x7328ef727aac - <unknown>
32: 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 1.88.0-nightly (4a0969e06 2025-05-05) running on x86_64-unknown-linux-gnu
note: compiler flags: -Z incremental-verify-ich=yes -C incremental=[REDACTED] -C debuginfo=2 -C link-dead-code=true -Z validate-mir
query stack during panic:
#0 [exportable_items] fetching all exportable items in a crate
#1 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0658`.
@rustbot label +F-export_stable
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Reproduce the ICE with the reduced Rust program in a.rs and the listed compiler flags. Start at compiler/rustc_passes/src/check_export.rs around line 314, following the exportable_items query and the visit_ty path. Done means this input no longer panics at unreachable code and instead produces compiler diagnostics or completes normally.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100