Closed
Description
snippet:
pub trait Future {}
pub trait Action {}
fn retry<A: Action>(action: A) -> impl Future {}
struct Core<T: Future> {}
impl<T: Future> Core<F> {
pub fn spawn(self) {}
}
fn main() {
let mut core = Core {};
for i in &[1, 2, 3, 4, 5] {
core.spawn(retry(action));
}
}
original code
original:
pub trait Future {
fn run(self);
}
impl<F> Future for F where Item: FnOnce() {
fn retry<A: Action>(action: A) -> impl Future<Item = (), Error = ()> {
action.run()
}
}
pub trait Action {
type Output: Future;
fn run(self) -> Self::Output;
}
impl<T: Action, F: FnOnce() -> T> Action for F {
type Output = T;
fn run(self) -> Self::Output {
self()
}
}
fn retry<A: Action>(action: A) -> impl Future {
action.handle()
}
struct Core<T: Future> {
vec: Vec<F>,
}
impl<T: Future> Core<F> {
pub fn spawn(self) where F: Future + 'static {
core.remove.push(f);
}
pub fn run(self) {
for f in self.vec.into_iter() {
f.run()
};
}
}
/*
The `nested` closure avoids the check of its lifetime here, if:
- the `nasted` closure is nested into the `action` closure, and
- the `action` closure is passed into the `retry` function, and
- the `retry` function take a generic by the `Action` trait argument, and
- the `Action` trait is implemented for an `Fn*` trait.
As a result, we get arbitrary values in variables and at best SIGSEGV.
*/
fn main() {
let mut core = Core { vec: Vec::new() };
for i in &[1, 2, 3, 4, 5] {
println!("Core::run", i);
let f = || { // The `lazy` closure
f()
};
let action = move || {
|| f() // The `nested` closure
};
core.spawn(retry(action));
}
core.run();
}
Version information
rustc 1.86.0-nightly (35c290817 2025-01-14)
binary: rustc
commit-hash: 35c2908177a17ca4e0acbc9013e42ee525ba155c
commit-date: 2025-01-14
host: x86_64-unknown-linux-gnu
release: 1.86.0-nightly
LLVM version: 19.1.6
Possibly related line of code:
rust/compiler/rustc_hir_typeck/src/demand.rs
Lines 403 to 415 in 35c2908
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc
Program output
error[E0412]: cannot find type `F` in this scope
--> /tmp/icemaker_global_tempdir.hbPlrcOQEpxc/rustc_testrunner_tmpdir_reporting.YPq7bZYDb2EU/mvce.rs:9:22
|
9 | impl<T: Future> Core<F> {
| ^
|
::: /home/matthias/.rustup/toolchains/master/lib/rustlib/src/rust/library/core/src/ops/function.rs:76:1
|
76 | pub trait Fn<Args: Tuple>: FnMut<Args> {
| -------------------------------------- similarly named trait `Fn` defined here
|
help: a trait with a similar name exists
|
9 | impl<T: Future> Core<Fn> {
| ~~
help: you might be missing a type parameter
|
9 | impl<T: Future, F> Core<F> {
| +++
error[E0425]: cannot find value `action` in this scope
--> /tmp/icemaker_global_tempdir.hbPlrcOQEpxc/rustc_testrunner_tmpdir_reporting.YPq7bZYDb2EU/mvce.rs:16:26
|
16 | core.spawn(retry(action));
| ^^^^^^ not found in this scope
error[E0392]: type parameter `T` is never used
--> /tmp/icemaker_global_tempdir.hbPlrcOQEpxc/rustc_testrunner_tmpdir_reporting.YPq7bZYDb2EU/mvce.rs:7:13
|
7 | struct Core<T: Future> {}
| ^ unused type parameter
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
error[E0277]: the trait bound `(): Future` is not satisfied
--> /tmp/icemaker_global_tempdir.hbPlrcOQEpxc/rustc_testrunner_tmpdir_reporting.YPq7bZYDb2EU/mvce.rs:5:35
|
5 | fn retry<A: Action>(action: A) -> impl Future {}
| ^^^^^^^^^^^ the trait `Future` is not implemented for `()`
|
help: this trait has no implementations, consider adding one
--> /tmp/icemaker_global_tempdir.hbPlrcOQEpxc/rustc_testrunner_tmpdir_reporting.YPq7bZYDb2EU/mvce.rs:1:1
|
1 | pub trait Future {}
| ^^^^^^^^^^^^^^^^
thread 'rustc' panicked at compiler/rustc_hir_typeck/src/demand.rs:409:53:
index out of bounds: the len is 1 but the index is 1
stack backtrace:
0: 0x76293fefec2a - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h343181add7067502
1: 0x762940612da6 - core::fmt::write::h4a7aadae0a1bc1aa
2: 0x76294159c3d1 - std::io::Write::write_fmt::h1778835c3c67b7e7
3: 0x76293fefea82 - std::sys::backtrace::BacktraceLock::print::h6b4eb1026a458107
4: 0x76293ff01027 - std::panicking::default_hook::{{closure}}::h794153a458ec0a99
5: 0x76293ff00e10 - std::panicking::default_hook::haa2577842079db42
6: 0x76293f0657e8 - std[f87fc13b1c9b189d]::panicking::update_hook::<alloc[8c45d6cf9cfd903f]::boxed::Box<rustc_driver_impl[b5cea8d0259ab78a]::install_ice_hook::{closure#1}>>::{closure#0}
7: 0x76293ff01873 - std::panicking::rust_panic_with_hook::h3d89a5b3bc51855c
8: 0x76293ff0156a - std::panicking::begin_panic_handler::{{closure}}::h6218397a7f283626
9: 0x76293feff0f9 - std::sys::backtrace::__rust_end_short_backtrace::h1c3cb871f8987430
10: 0x76293ff0122d - rust_begin_unwind
11: 0x76293cba68d0 - core::panicking::panic_fmt::h9f9d58009f0431b1
12: 0x76293e6e03c9 - core::panicking::panic_bounds_check::h28c35d67f308dc8e
13: 0x76293f2e3303 - <core[60f4c6f00ff91c40]::slice::iter::Iter<&rustc_hir[d42cc4700ac42360]::hir::Expr> as core[60f4c6f00ff91c40]::iter::traits::double_ended::DoubleEndedIterator>::try_rfold::<(), core[60f4c6f00ff91c40]::iter::traits::iterator::Iterator::find_map::check<&&rustc_hir[d42cc4700ac42360]::hir::Expr, rustc_middle[7d18ff6d534e138c]::ty::Ty, <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::note_source_of_type_mismatch_constraint::{closure#3}>::{closure#0}, core[60f4c6f00ff91c40]::ops::control_flow::ControlFlow<rustc_middle[7d18ff6d534e138c]::ty::Ty>>
14: 0x76293f35d928 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::note_source_of_type_mismatch_constraint
15: 0x76293f386665 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::report_arg_errors
16: 0x7629407608d0 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_argument_types
17: 0x76294136e4d6 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
18: 0x762941357c0f - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_block
19: 0x76294135f4f3 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
20: 0x76294135305c - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_match::{closure#0}
21: 0x7629413609dd - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
22: 0x7629413591f1 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_block
23: 0x7629413641a8 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
24: 0x76294135305c - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_match::{closure#0}
25: 0x7629413609dd - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
26: 0x762941361773 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
27: 0x762941357d01 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_block
28: 0x76294135f4f3 - <rustc_hir_typeck[7437378b43a6ded6]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
29: 0x762940c5c4c0 - rustc_hir_typeck[7437378b43a6ded6]::check::check_fn
30: 0x762940c6617d - rustc_hir_typeck[7437378b43a6ded6]::typeck_with_fallback::{closure#0}
31: 0x762940c6418c - rustc_query_impl[cb4674ae863c9cf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cb4674ae863c9cf]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[7d18ff6d534e138c]::query::erase::Erased<[u8; 8usize]>>
32: 0x762940c4ee8e - rustc_query_system[b56cf2761e1d5f32]::query::plumbing::try_execute_query::<rustc_query_impl[cb4674ae863c9cf]::DynamicConfig<rustc_data_structures[9413300d1cf0cd07]::vec_cache::VecCache<rustc_span[32ed8b15aa28102c]::def_id::LocalDefId, rustc_middle[7d18ff6d534e138c]::query::erase::Erased<[u8; 8usize]>, rustc_query_system[b56cf2761e1d5f32]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[cb4674ae863c9cf]::plumbing::QueryCtxt, false>
33: 0x762940c4e063 - rustc_query_impl[cb4674ae863c9cf]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
34: 0x762940c4dd1d - <rustc_middle[7d18ff6d534e138c]::hir::map::Map>::par_body_owners::<rustc_hir_analysis[c09c58fe15d469e5]::check_crate::{closure#4}>::{closure#0}
35: 0x762940c4bdd1 - rustc_hir_analysis[c09c58fe15d469e5]::check_crate
36: 0x7629408f8d68 - rustc_interface[9cdea11426ea32ce]::passes::run_required_analyses
37: 0x7629415a025e - rustc_interface[9cdea11426ea32ce]::passes::analysis
38: 0x7629415a022f - rustc_query_impl[cb4674ae863c9cf]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cb4674ae863c9cf]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[7d18ff6d534e138c]::query::erase::Erased<[u8; 0usize]>>
39: 0x7629415c6215 - rustc_query_system[b56cf2761e1d5f32]::query::plumbing::try_execute_query::<rustc_query_impl[cb4674ae863c9cf]::DynamicConfig<rustc_query_system[b56cf2761e1d5f32]::query::caches::SingleCache<rustc_middle[7d18ff6d534e138c]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[cb4674ae863c9cf]::plumbing::QueryCtxt, false>
40: 0x7629415c5f4e - rustc_query_impl[cb4674ae863c9cf]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
41: 0x7629416433de - rustc_interface[9cdea11426ea32ce]::passes::create_and_enter_global_ctxt::<core[60f4c6f00ff91c40]::option::Option<rustc_interface[9cdea11426ea32ce]::queries::Linker>, rustc_driver_impl[b5cea8d0259ab78a]::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}
42: 0x762941635e16 - rustc_interface[9cdea11426ea32ce]::interface::run_compiler::<(), rustc_driver_impl[b5cea8d0259ab78a]::run_compiler::{closure#0}>::{closure#1}
43: 0x7629414b7647 - std[f87fc13b1c9b189d]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[9cdea11426ea32ce]::util::run_in_thread_with_globals<rustc_interface[9cdea11426ea32ce]::util::run_in_thread_pool_with_globals<rustc_interface[9cdea11426ea32ce]::interface::run_compiler<(), rustc_driver_impl[b5cea8d0259ab78a]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
44: 0x7629414b7ae0 - <<std[f87fc13b1c9b189d]::thread::Builder>::spawn_unchecked_<rustc_interface[9cdea11426ea32ce]::util::run_in_thread_with_globals<rustc_interface[9cdea11426ea32ce]::util::run_in_thread_pool_with_globals<rustc_interface[9cdea11426ea32ce]::interface::run_compiler<(), rustc_driver_impl[b5cea8d0259ab78a]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[60f4c6f00ff91c40]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
45: 0x7629414b90c1 - std::sys::pal::unix::thread::Thread::new::thread_start::h0b52359edc81c287
46: 0x76293b8a339d - <unknown>
47: 0x76293b92849c - <unknown>
48: 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 1.86.0-nightly (35c290817 2025-01-14) running on x86_64-unknown-linux-gnu
query stack during panic:
#0 [typeck] type-checking `main`
#1 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 4 previous errors
Some errors have detailed explanations: E0277, E0392, E0412, E0425.
For more information about an error, try `rustc --explain E0277`.
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Category: This is a bug.Call for participation: An issue has been fixed and does not reproduce, but no test has been added.Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️Status: A bisection has been found for this issueStatus: A Minimal Complete and Verifiable Example has been found for this issueRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the types team, which will review and decide on the PR/issue.