Open
Description
snippet:
//@compile-flags: -Zvalidate-mir -Zinline-mir=yes
use std::mem::ManuallyDrop;
use std::{
future::{async_drop_in_place, Future},
pin::{pin, Pin},
};
fn a() {
b(bar(0))
}
async fn bar(c: usize);
fn b<d>(e: d) {
let mut f = pin!(ManuallyDrop::new(e));
let mut fut = { Pin::map_unchecked_mut(f, |g| &mut **g) };
let mut context;
let h = async_drop_in_place(fut.get_unchecked_mut());
let mut i = pin!(h);
match i.poll( context) {
j }
}Version information
rustc 1.89.0-nightly (718ddf660 2025-05-12)
binary: rustc
commit-hash: 718ddf660e6a1802c39b4962cf7eaa4db57025ef
commit-date: 2025-05-12
host: x86_64-unknown-linux-gnu
release: 1.89.0-nightly
LLVM version: 20.1.4
Possibly related line of code:
rust/compiler/rustc_mir_transform/src/elaborate_drop.rs
Lines 1248 to 1260 in 718ddf6
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Zvalidate-mir -Zinline-mir=yes
Program output
error[E0670]: `async fn` is not permitted in Rust 2015
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:9:1
|
9 | async fn bar(c: usize);
| ^^^^^ to use `async fn`, switch to Rust 2018 or later
|
= help: pass `--edition 2024` to `rustc`
= note: for more on editions, read https://doc.rust-lang.org/edition-guide
error: free function without a body
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:9:1
|
9 | async fn bar(c: usize);
| ^^^^^^^^^^^^^^^^^^^^^^-
| |
| help: provide a definition for the function: `{ <body> }`
error: `match` arm with no body
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:17:23
|
17 | j }
| ^
|
help: add a body after the pattern
|
17 | j => { todo!() } }
| ++++++++++++++
warning: type parameter `d` should have an upper camel case name
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:10:6
|
10 | fn b<d>(e: d) {
| ^ help: convert the identifier to upper camel case: `D`
|
= note: `#[warn(non_camel_case_types)]` on by default
error[E0601]: `main` function not found in crate `mvce`
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:18:2
|
18 | }
| ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs`
error[E0658]: use of unstable library feature `async_drop`
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:3:14
|
3 | future::{async_drop_in_place, Future},
| ^^^^^^^^^^^^^^^^^^^
|
= note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
= help: add `#![feature(async_drop)]` to the crate attributes to enable
= note: this compiler was built on 2025-05-12; consider upgrading it if it is out of date
error[E0658]: use of unstable library feature `async_drop`
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:14:13
|
14 | let h = async_drop_in_place(fut.get_unchecked_mut());
| ^^^^^^^^^^^^^^^^^^^
|
= note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
= help: add `#![feature(async_drop)]` to the crate attributes to enable
= note: this compiler was built on 2025-05-12; consider upgrading it if it is out of date
warning: unused variable: `j`
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:17:23
|
17 | j }
| ^ help: if this is intentional, prefix it with an underscore: `_j`
|
= note: `#[warn(unused_variables)]` on by default
error[E0133]: call to unsafe function `Pin::<&'a mut T>::map_unchecked_mut` is unsafe and requires unsafe function or block
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:12:21
|
12 | let mut fut = { Pin::map_unchecked_mut(f, |g| &mut **g) };
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
error[E0133]: call to unsafe function `async_drop_in_place` is unsafe and requires unsafe function or block
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:14:13
|
14 | let h = async_drop_in_place(fut.get_unchecked_mut());
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
error[E0133]: call to unsafe function `Pin::<&'a mut T>::get_unchecked_mut` is unsafe and requires unsafe function or block
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:14:33
|
14 | let h = async_drop_in_place(fut.get_unchecked_mut());
| ^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
warning: variable does not need to be mutable
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:11:9
|
11 | let mut f = pin!(ManuallyDrop::new(e));
| ----^
| |
| help: remove this `mut`
|
= note: `#[warn(unused_mut)]` on by default
warning: variable does not need to be mutable
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:12:9
|
12 | let mut fut = { Pin::map_unchecked_mut(f, |g| &mut **g) };
| ----^^^
| |
| help: remove this `mut`
warning: variable does not need to be mutable
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:15:9
|
15 | let mut i = pin!(h);
| ----^
| |
| help: remove this `mut`
error[E0381]: used binding `context` isn't initialized
--> /tmp/icemaker_global_tempdir.tcPGNTRpBJ9s/rustc_testrunner_tmpdir_reporting.XOmIYrPbp6kH/mvce.rs:16:19
|
13 | let mut context;
| ----------- binding declared here but left uninitialized
...
16 | match i.poll( context) {
| ^^^^^^^ `context` used here but it isn't initialized
|
help: consider assigning a value
|
13 | let mut context = &mut /* value */;
| ++++++++++++++++++
error: internal compiler error: compiler/rustc_mir_transform/src/elaborate_drop.rs:1254:18: open drop from non-ADT `{type error}`
--> /home/matthias/.rustup/toolchains/master/lib/rustlib/src/rust/library/core/src/future/async_drop.rs:48:70
|
48 | pub async unsafe fn async_drop_in_place<T: ?Sized>(_to_drop: *mut T) {
| ______________________________________________________________________^
... |
51 | | }
| |_^
thread 'rustc' panicked at compiler/rustc_mir_transform/src/elaborate_drop.rs:1254:18:
Box<dyn Any>
stack backtrace:
0: 0x78a0ab959fb3 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::hd03fa4624d6a43ff
1: 0x78a0ac005987 - core::fmt::write::h99c6bd700e41fe5b
2: 0x78a0ad0b4091 - std::io::Write::write_fmt::h8fdba04fd8ac1437
3: 0x78a0ab959e12 - std::sys::backtrace::BacktraceLock::print::ha37796b30caa3dee
4: 0x78a0ab95da0a - std::panicking::default_hook::{{closure}}::h2be5a8e7cd709dcc
5: 0x78a0ab95d58f - std::panicking::default_hook::h652a4375123f2a56
6: 0x78a0aa98c873 - std[56b07bdfd6b41829]::panicking::update_hook::<alloc[763664f815bf0fa8]::boxed::Box<rustc_driver_impl[fb64ae308f02562]::install_ice_hook::{closure#1}>>::{closure#0}
7: 0x78a0ab95e283 - std::panicking::rust_panic_with_hook::h4f131a958fbdba61
8: 0x78a0aa9c85f1 - std[56b07bdfd6b41829]::panicking::begin_panic::<rustc_errors[b8a92ed9b61c1989]::ExplicitBug>::{closure#0}
9: 0x78a0aa9bc626 - std[56b07bdfd6b41829]::sys::backtrace::__rust_end_short_backtrace::<std[56b07bdfd6b41829]::panicking::begin_panic<rustc_errors[b8a92ed9b61c1989]::ExplicitBug>::{closure#0}, !>
10: 0x78a0aa9b8ce9 - std[56b07bdfd6b41829]::panicking::begin_panic::<rustc_errors[b8a92ed9b61c1989]::ExplicitBug>
11: 0x78a0aa9d2c71 - <rustc_errors[b8a92ed9b61c1989]::diagnostic::BugAbort as rustc_errors[b8a92ed9b61c1989]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
12: 0x78a0aafa0adc - <rustc_errors[b8a92ed9b61c1989]::DiagCtxtHandle>::span_bug::<rustc_span[d026ac1b2b8daa7c]::span_encoding::Span, alloc[763664f815bf0fa8]::string::String>
13: 0x78a0ab03ecb7 - rustc_middle[60b471758888797e]::util::bug::opt_span_bug_fmt::<rustc_span[d026ac1b2b8daa7c]::span_encoding::Span>::{closure#0}
14: 0x78a0ab01723a - rustc_middle[60b471758888797e]::ty::context::tls::with_opt::<rustc_middle[60b471758888797e]::util::bug::opt_span_bug_fmt<rustc_span[d026ac1b2b8daa7c]::span_encoding::Span>::{closure#0}, !>::{closure#0}
15: 0x78a0ab0170ab - rustc_middle[60b471758888797e]::ty::context::tls::with_context_opt::<rustc_middle[60b471758888797e]::ty::context::tls::with_opt<rustc_middle[60b471758888797e]::util::bug::opt_span_bug_fmt<rustc_span[d026ac1b2b8daa7c]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
16: 0x78a0a93f14c7 - rustc_middle[60b471758888797e]::util::bug::span_bug_fmt::<rustc_span[d026ac1b2b8daa7c]::span_encoding::Span>
17: 0x78a0ac897c24 - <rustc_mir_transform[4a4e9cf23a9606fd]::elaborate_drop::DropCtxt<rustc_mir_transform[4a4e9cf23a9606fd]::shim::DropShimElaborator>>::elaborate_drop
18: 0x78a0ac891851 - rustc_mir_transform[4a4e9cf23a9606fd]::shim::make_shim
19: 0x78a0ac88f82f - rustc_query_impl[cf6f12f07b5d9141]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_shims::dynamic_query::{closure#2}::{closure#0}, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 8usize]>>
20: 0x78a0ac88f7e3 - <rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_shims::dynamic_query::{closure#2} as core[604f71d46da0bdba]::ops::function::FnOnce<(rustc_middle[60b471758888797e]::ty::context::TyCtxt, rustc_middle[60b471758888797e]::ty::instance::InstanceKind)>>::call_once
21: 0x78a0ac852d8c - rustc_query_system[620f1d082c8e701b]::query::plumbing::try_execute_query::<rustc_query_impl[cf6f12f07b5d9141]::DynamicConfig<rustc_query_system[620f1d082c8e701b]::query::caches::DefaultCache<rustc_middle[60b471758888797e]::ty::instance::InstanceKind, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[cf6f12f07b5d9141]::plumbing::QueryCtxt, false>
22: 0x78a0ac852aaa - rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_shims::get_query_non_incr::__rust_end_short_backtrace
23: 0x78a0ac84d95e - <rustc_middle[60b471758888797e]::ty::context::TyCtxt>::instance_mir
24: 0x78a0aca7a70f - rustc_mir_transform[4a4e9cf23a9606fd]::inline::cycle::mir_inliner_callees
25: 0x78a0aca7a574 - rustc_query_impl[cf6f12f07b5d9141]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_inliner_callees::dynamic_query::{closure#2}::{closure#0}, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 16usize]>>
26: 0x78a0aca7a543 - <rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_inliner_callees::dynamic_query::{closure#2} as core[604f71d46da0bdba]::ops::function::FnOnce<(rustc_middle[60b471758888797e]::ty::context::TyCtxt, rustc_middle[60b471758888797e]::ty::instance::InstanceKind)>>::call_once
27: 0x78a0ac853a47 - rustc_query_system[620f1d082c8e701b]::query::plumbing::try_execute_query::<rustc_query_impl[cf6f12f07b5d9141]::DynamicConfig<rustc_query_system[620f1d082c8e701b]::query::caches::DefaultCache<rustc_middle[60b471758888797e]::ty::instance::InstanceKind, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[cf6f12f07b5d9141]::plumbing::QueryCtxt, false>
28: 0x78a0ac85373b - rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_inliner_callees::get_query_non_incr::__rust_end_short_backtrace
29: 0x78a0acff4d76 - rustc_mir_transform[4a4e9cf23a9606fd]::inline::cycle::mir_callgraph_reachable::process
30: 0x78a0acff519f - rustc_mir_transform[4a4e9cf23a9606fd]::inline::cycle::mir_callgraph_reachable::process
31: 0x78a0acff4544 - rustc_mir_transform[4a4e9cf23a9606fd]::inline::cycle::mir_callgraph_reachable
32: 0x78a0acff4369 - rustc_query_impl[cf6f12f07b5d9141]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_callgraph_reachable::dynamic_query::{closure#2}::{closure#0}, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 1usize]>>
33: 0x78a0acff4339 - <rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_callgraph_reachable::dynamic_query::{closure#2} as core[604f71d46da0bdba]::ops::function::FnOnce<(rustc_middle[60b471758888797e]::ty::context::TyCtxt, (rustc_middle[60b471758888797e]::ty::instance::Instance, rustc_span[d026ac1b2b8daa7c]::def_id::LocalDefId))>>::call_once
34: 0x78a0ac851dac - rustc_query_system[620f1d082c8e701b]::query::plumbing::try_execute_query::<rustc_query_impl[cf6f12f07b5d9141]::DynamicConfig<rustc_query_system[620f1d082c8e701b]::query::caches::DefaultCache<(rustc_middle[60b471758888797e]::ty::instance::Instance, rustc_span[d026ac1b2b8daa7c]::def_id::LocalDefId), rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[cf6f12f07b5d9141]::plumbing::QueryCtxt, false>
35: 0x78a0ac851aa8 - rustc_query_impl[cf6f12f07b5d9141]::query_impl::mir_callgraph_reachable::get_query_non_incr::__rust_end_short_backtrace
36: 0x78a0ac8a2a7b - rustc_mir_transform[4a4e9cf23a9606fd]::inline::process_blocks::<rustc_mir_transform[4a4e9cf23a9606fd]::inline::NormalInliner>
37: 0x78a0ac8cd31a - <rustc_mir_transform[4a4e9cf23a9606fd]::inline::Inline as rustc_mir_transform[4a4e9cf23a9606fd]::pass_manager::MirPass>::run_pass
38: 0x78a0ac00383d - rustc_mir_transform[4a4e9cf23a9606fd]::pass_manager::run_passes_inner
39: 0x78a0aca7da03 - rustc_mir_transform[4a4e9cf23a9606fd]::run_optimization_passes
40: 0x78a0aca7b2fb - rustc_mir_transform[4a4e9cf23a9606fd]::optimized_mir
41: 0x78a0aca7ae9d - rustc_query_impl[cf6f12f07b5d9141]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cf6f12f07b5d9141]::query_impl::optimized_mir::dynamic_query::{closure#2}::{closure#0}, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 8usize]>>
42: 0x78a0ac450e3f - rustc_query_system[620f1d082c8e701b]::query::plumbing::try_execute_query::<rustc_query_impl[cf6f12f07b5d9141]::DynamicConfig<rustc_query_system[620f1d082c8e701b]::query::caches::DefIdCache<rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[cf6f12f07b5d9141]::plumbing::QueryCtxt, false>
43: 0x78a0ac450262 - rustc_query_impl[cf6f12f07b5d9141]::query_impl::optimized_mir::get_query_non_incr::__rust_end_short_backtrace
44: 0x78a0ac84d286 - <rustc_middle[60b471758888797e]::ty::context::TyCtxt>::instance_mir
45: 0x78a0ac4b585f - rustc_interface[52ab4bdc9c3114ed]::passes::run_required_analyses
46: 0x78a0acfbb49e - rustc_interface[52ab4bdc9c3114ed]::passes::analysis
47: 0x78a0acfbb475 - rustc_query_impl[cf6f12f07b5d9141]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[cf6f12f07b5d9141]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 0usize]>>
48: 0x78a0acf2cdba - rustc_query_system[620f1d082c8e701b]::query::plumbing::try_execute_query::<rustc_query_impl[cf6f12f07b5d9141]::DynamicConfig<rustc_query_system[620f1d082c8e701b]::query::caches::SingleCache<rustc_middle[60b471758888797e]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[cf6f12f07b5d9141]::plumbing::QueryCtxt, false>
49: 0x78a0acf2ca8f - rustc_query_impl[cf6f12f07b5d9141]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
50: 0x78a0ad1fdc07 - rustc_interface[52ab4bdc9c3114ed]::passes::create_and_enter_global_ctxt::<core[604f71d46da0bdba]::option::Option<rustc_interface[52ab4bdc9c3114ed]::queries::Linker>, rustc_driver_impl[fb64ae308f02562]::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}
51: 0x78a0ad0f9fe6 - rustc_interface[52ab4bdc9c3114ed]::interface::run_compiler::<(), rustc_driver_impl[fb64ae308f02562]::run_compiler::{closure#0}>::{closure#1}
52: 0x78a0ad0aacfe - std[56b07bdfd6b41829]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[52ab4bdc9c3114ed]::util::run_in_thread_with_globals<rustc_interface[52ab4bdc9c3114ed]::util::run_in_thread_pool_with_globals<rustc_interface[52ab4bdc9c3114ed]::interface::run_compiler<(), rustc_driver_impl[fb64ae308f02562]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
53: 0x78a0ad0ab16b - <<std[56b07bdfd6b41829]::thread::Builder>::spawn_unchecked_<rustc_interface[52ab4bdc9c3114ed]::util::run_in_thread_with_globals<rustc_interface[52ab4bdc9c3114ed]::util::run_in_thread_pool_with_globals<rustc_interface[52ab4bdc9c3114ed]::interface::run_compiler<(), rustc_driver_impl[fb64ae308f02562]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[604f71d46da0bdba]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
54: 0x78a0ad0ac56b - std::sys::pal::unix::thread::Thread::new::thread_start::he52776061f67c85f
55: 0x78a0a6ea370a - <unknown>
56: 0x78a0a6f27aac - <unknown>
57: 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: please make sure that you have updated to the latest nightly
note: rustc 1.89.0-nightly (718ddf660 2025-05-12) running on x86_64-unknown-linux-gnu
note: compiler flags: -Z validate-mir -Z inline-mir=yes -Z dump-mir-dir=dir
query stack during panic:
#0 [mir_shims] generating MIR shim for `core::future::async_drop::async_drop_in_place::{closure#0}`, instance=AsyncDropGlue(DefId(2:15267 ~ core[604f]::future::async_drop::async_drop_in_place::{closure#0}), Coroutine(DefId(2:15267 ~ core[604f]::future::async_drop::async_drop_in_place::{closure#0}), [{type error}, (), core::future::ResumeTy, (), (), CoroutineWitness(DefId(2:15267 ~ core[604f]::future::async_drop::async_drop_in_place::{closure#0}), [{type error}]), (*mut {type error},)]))
#1 [mir_inliner_callees] computing all local function calls in `core::future::async_drop::async_drop_in_place::{closure#0}`
#2 [mir_callgraph_reachable] computing if `b::<{type error}>` (transitively) calls `a`
#3 [optimized_mir] optimizing MIR for `a`
#4 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 11 previous errors; 5 warnings emitted
Some errors have detailed explanations: E0133, E0381, E0601, E0658, E0670.
For more information about an error, try `rustc --explain E0133`.
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Unstable option: MIR validationCategory: This is a bug.Call for participation: This issue has a repro, but needs a Minimal Complete and Verifiable Example`#![feature(async_drop)]`Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️Status: a bisection has been found for this issueRelevant to the compiler team, which will review and decide on the PR/issue.This issue requires the use of incomplete features.