Closed
Description
auto-reduced (treereduce-rust):
mod assert {
use std::mem::{Assume, BikeshedIntrinsicFrom};
pub fn is_transmutable<Src, Dst>()
where
Dst: BikeshedIntrinsicFrom<Src>,
{
}
}
#[repr(u32)]
enum Ox00 {
V = 0x00,
}
enum Ox01 {
V = 0x01,
}
#[repr(C, packed(2))]
enum OxFF {
V = 0xFF,
}
fn test() {
#[derive]
union Superset {
a: Ox00,
b: OxFF,
b: Ox01,
}
assert::is_transmutable::<Superset, Subset>();
}
original:
#![crate_type = "lib"]
#![feature(allow)]
#![allow(dead_code, incomplete_features, non_camel_case_types)]
mod assert {
use std::mem::{Assume, BikeshedIntrinsicFrom};
pub fn is_transmutable<Src, Dst>()
where
Dst: BikeshedIntrinsicFrom<Src, { Assume::SAFETY.and(Assume::VALIDITY) }>
{}
}
#[derive(Clone, Copy)] #[repr(u32)] enum Ox00 { V = 0x00 }
#[derive(Clone, Copy)] #[repr(u8)] enum Ox01 { V = 0x01 }
#[derive(Clone, Copy)] #[repr(C, packed(2))] enum OxFF { V = 0xFF }
fn test() {
#[derive]
union Subset {
a: (),
b: V1u8,
}
#[packed(C)]
union Superset {
a: Ox00,
b: OxFF,
b: Ox01,
}
assert::is_transmutable::<Superset, Subset>(); //~ ERROR cannot be safely transmuted
}Version information
rustc 1.81.0-nightly (d929a42a6 2024-06-25)
binary: rustc
commit-hash: d929a42a664c026167800801b26d734db925314f
commit-date: 2024-06-25
host: x86_64-unknown-linux-gnu
release: 1.81.0-nightly
LLVM version: 18.1.7
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc
Program output
error: malformed `derive` attribute input
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:24:5
|
24 | #[derive]
| ^^^^^^^^^ help: must be of the form: `#[derive(Trait1, Trait2, ...)]`
error[E0412]: cannot find type `Subset` in this scope
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:32:41
|
32 | assert::is_transmutable::<Superset, Subset>();
| ^^^^^^ not found in this scope
|
help: you might be missing a type parameter
|
23 | fn test<Subset>() {
| ++++++++
warning: unused import: `Assume`
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:2:20
|
2 | use std::mem::{Assume, BikeshedIntrinsicFrom};
| ^^^^^^
|
= note: `#[warn(unused_imports)]` on by default
error[E0601]: `main` function not found in crate `mvce`
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:33:2
|
33 | }
| ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs`
error[E0517]: attribute should be applied to a struct or union
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:18:11
|
18 | #[repr(C, packed(2))]
| ^^^^^^^^^
19 | / enum OxFF {
20 | | V = 0xFF,
21 | | }
| |_- not a struct or union
error[E0658]: use of unstable library feature 'transmutability'
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:2:20
|
2 | use std::mem::{Assume, BikeshedIntrinsicFrom};
| ^^^^^^
|
= note: see issue #99571 <https://github.com/rust-lang/rust/issues/99571> for more information
= help: add `#![feature(transmutability)]` to the crate attributes to enable
= note: this compiler was built on 2024-06-25; consider upgrading it if it is out of date
error[E0658]: use of unstable library feature 'transmutability'
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:2:28
|
2 | use std::mem::{Assume, BikeshedIntrinsicFrom};
| ^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #99571 <https://github.com/rust-lang/rust/issues/99571> for more information
= help: add `#![feature(transmutability)]` to the crate attributes to enable
= note: this compiler was built on 2024-06-25; consider upgrading it if it is out of date
error[E0658]: use of unstable library feature 'transmutability'
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:6:14
|
6 | Dst: BikeshedIntrinsicFrom<Src>,
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #99571 <https://github.com/rust-lang/rust/issues/99571> for more information
= help: add `#![feature(transmutability)]` to the crate attributes to enable
= note: this compiler was built on 2024-06-25; consider upgrading it if it is out of date
error[E0124]: field `b` is already declared
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:29:9
|
28 | b: OxFF,
| ------- `b` first declared here
29 | b: Ox01,
| ^^^^^^^ field already declared
error[E0740]: field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
--> /tmp/icemaker_global_tempdir.WonAMZI2vcAF/rustc_testrunner_tmpdir_reporting.xuyJdDymg62q/mvce.rs:27:9
|
27 | a: Ox00,
| ^^^^^^^
|
= note: union fields must not have drop side-effects, which is currently enforced via either `Copy` or `ManuallyDrop<...>`
help: wrap the field type in `ManuallyDrop<...>`
|
27 | a: std::mem::ManuallyDrop<Ox00>,
| +++++++++++++++++++++++ +
thread 'rustc' panicked at /rustc/d929a42a664c026167800801b26d734db925314f/compiler/rustc_abi/src/layout.rs:289:29:
assertion `left == right` failed: non-Aggregate field with matching ABI but differing alignment
left: Align(4 bytes)
right: Align(2 bytes)
stack backtrace:
0: 0x777bc94142e5 - std::backtrace_rs::backtrace::libunwind::trace::h3816f17667167091
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/../../backtrace/src/backtrace/libunwind.rs:116:5
1: 0x777bc94142e5 - std::backtrace_rs::backtrace::trace_unsynchronized::h05c1a74390e79138
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
2: 0x777bc94142e5 - std::sys::backtrace::_print_fmt::hf9f67f450e2340b3
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/sys/backtrace.rs:68:5
3: 0x777bc94142e5 - <std::sys::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hd0470f4740d6f066
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/sys/backtrace.rs:44:22
4: 0x777bc9463ceb - core::fmt::rt::Argument::fmt::h70b8a6b09781c530
at /rustc/d929a42a664c026167800801b26d734db925314f/library/core/src/fmt/rt.rs:165:63
5: 0x777bc9463ceb - core::fmt::write::hafea0839d2bbb3f2
at /rustc/d929a42a664c026167800801b26d734db925314f/library/core/src/fmt/mod.rs:1168:21
6: 0x777bc9408f6f - std::io::Write::write_fmt::h781fa7911c53c2fa
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/io/mod.rs:1835:15
7: 0x777bc94140be - std::sys::backtrace::_print::h864675b81ca0e917
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/sys/backtrace.rs:47:5
8: 0x777bc94140be - std::sys::backtrace::print::h077604854516c949
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/sys/backtrace.rs:34:9
9: 0x777bc9416a09 - std::panicking::default_hook::{{closure}}::h0655bbcac1b3559e
10: 0x777bc94167ac - std::panicking::default_hook::ha9e013cc76e074dd
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/panicking.rs:292:9
11: 0x777bc59eac90 - std[e6dd88f179d4d596]::panicking::update_hook::<alloc[7519215c1642967c]::boxed::Box<rustc_driver_impl[6d6094f07793e4a9]::install_ice_hook::{closure#0}>>::{closure#0}
12: 0x777bc94172df - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::haac7baf64299a07d
at /rustc/d929a42a664c026167800801b26d734db925314f/library/alloc/src/boxed.rs:2078:9
13: 0x777bc94172df - std::panicking::rust_panic_with_hook::h9bfa469549e655b8
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/panicking.rs:804:13
14: 0x777bc9416f07 - std::panicking::begin_panic_handler::{{closure}}::h4a967f6ef7ab4640
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/panicking.rs:670:13
15: 0x777bc94147a9 - std::sys::backtrace::__rust_end_short_backtrace::h6bde84250dc9cd8b
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/sys/backtrace.rs:171:18
16: 0x777bc9416be4 - rust_begin_unwind
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/panicking.rs:661:5
17: 0x777bc94602a3 - core::panicking::panic_fmt::h036234c821d91466
at /rustc/d929a42a664c026167800801b26d734db925314f/library/core/src/panicking.rs:74:14
18: 0x777bc946087f - core::panicking::assert_failed_inner::h6886c5ce8b27c112
at /rustc/d929a42a664c026167800801b26d734db925314f/library/core/src/panicking.rs:405:23
19: 0x777bc6742f17 - core[672c7616ff9a88f5]::panicking::assert_failed::<rustc_abi[75a4f7491f97790a]::Align, rustc_abi[75a4f7491f97790a]::Align>
20: 0x777bc775ea4e - rustc_ty_utils[91a81cae3f51d4c]::layout::layout_of_uncached
21: 0x777bc774ce0b - rustc_ty_utils[91a81cae3f51d4c]::layout::layout_of
22: 0x777bc774cd91 - rustc_query_impl[b034b92d40b1d47d]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b034b92d40b1d47d]::query_impl::layout_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 16usize]>>
23: 0x777bc774c0b6 - rustc_query_system[4a94863d7e85f976]::query::plumbing::try_execute_query::<rustc_query_impl[b034b92d40b1d47d]::DynamicConfig<rustc_query_system[4a94863d7e85f976]::query::caches::DefaultCache<rustc_middle[e321b4b4f2134162]::ty::ParamEnvAnd<rustc_middle[e321b4b4f2134162]::ty::Ty>, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 16usize]>>, false, true, false>, rustc_query_impl[b034b92d40b1d47d]::plumbing::QueryCtxt, false>
24: 0x777bc774bd45 - rustc_query_impl[b034b92d40b1d47d]::query_impl::layout_of::get_query_non_incr::__rust_end_short_backtrace
25: 0x777bc671d5cc - rustc_middle[e321b4b4f2134162]::query::plumbing::query_get_at::<rustc_query_system[4a94863d7e85f976]::query::caches::DefaultCache<rustc_middle[e321b4b4f2134162]::ty::ParamEnvAnd<rustc_middle[e321b4b4f2134162]::ty::Ty>, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 16usize]>>>
26: 0x777bc6734531 - <rustc_transmute[483028c4aa667a77]::rustc::TransmuteTypeEnv>::is_transmutable
27: 0x777bc79db58f - <rustc_trait_selection[acad18ec578eab22]::traits::select::SelectionContext>::confirm_candidate
28: 0x777bc7472f11 - <rustc_trait_selection[acad18ec578eab22]::traits::select::SelectionContext>::evaluate_trait_predicate_recursively
29: 0x777bc746ce97 - <rustc_trait_selection[acad18ec578eab22]::traits::select::SelectionContext>::evaluate_root_obligation
30: 0x777bc746b215 - rustc_traits[8a90ea068024d15f]::evaluate_obligation::evaluate_obligation
31: 0x777bc746aba9 - rustc_query_impl[b034b92d40b1d47d]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b034b92d40b1d47d]::query_impl::evaluate_obligation::dynamic_query::{closure#2}::{closure#0}, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 2usize]>>
32: 0x777bc746a10f - rustc_query_system[4a94863d7e85f976]::query::plumbing::try_execute_query::<rustc_query_impl[b034b92d40b1d47d]::DynamicConfig<rustc_query_system[4a94863d7e85f976]::query::caches::DefaultCache<rustc_type_ir[567596a8266d8233]::canonical::Canonical<rustc_middle[e321b4b4f2134162]::ty::context::TyCtxt, rustc_middle[e321b4b4f2134162]::ty::ParamEnvAnd<rustc_middle[e321b4b4f2134162]::ty::predicate::Predicate>>, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 2usize]>>, false, false, false>, rustc_query_impl[b034b92d40b1d47d]::plumbing::QueryCtxt, false>
33: 0x777bc7469d64 - rustc_query_impl[b034b92d40b1d47d]::query_impl::evaluate_obligation::get_query_non_incr::__rust_end_short_backtrace
34: 0x777bc38caa92 - <rustc_trait_selection[acad18ec578eab22]::traits::fulfill::FulfillProcessor as rustc_data_structures[66d2db66d3aeea18]::obligation_forest::ObligationProcessor>::process_obligation
35: 0x777bc70081e7 - <rustc_data_structures[66d2db66d3aeea18]::obligation_forest::ObligationForest<rustc_trait_selection[acad18ec578eab22]::traits::fulfill::PendingPredicateObligation>>::process_obligations::<rustc_trait_selection[acad18ec578eab22]::traits::fulfill::FulfillProcessor>
36: 0x777bc3bbbfea - <rustc_hir_typeck[673ed4476fae1319]::fn_ctxt::FnCtxt>::confirm_builtin_call
37: 0x777bc7bb4c5d - <rustc_hir_typeck[673ed4476fae1319]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
38: 0x777bc7baedf6 - <rustc_hir_typeck[673ed4476fae1319]::fn_ctxt::FnCtxt>::check_block_with_expected
39: 0x777bc7bb5760 - <rustc_hir_typeck[673ed4476fae1319]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
40: 0x777bc72f91f6 - rustc_hir_typeck[673ed4476fae1319]::check::check_fn
41: 0x777bc72ed054 - rustc_hir_typeck[673ed4476fae1319]::typeck
42: 0x777bc72eca9d - rustc_query_impl[b034b92d40b1d47d]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b034b92d40b1d47d]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 8usize]>>
43: 0x777bc736a073 - rustc_query_system[4a94863d7e85f976]::query::plumbing::try_execute_query::<rustc_query_impl[b034b92d40b1d47d]::DynamicConfig<rustc_query_system[4a94863d7e85f976]::query::caches::VecCache<rustc_span[31538c27a715cd64]::def_id::LocalDefId, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[b034b92d40b1d47d]::plumbing::QueryCtxt, false>
44: 0x777bc736924d - rustc_query_impl[b034b92d40b1d47d]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
45: 0x777bc7368e44 - <rustc_middle[e321b4b4f2134162]::hir::map::Map>::par_body_owners::<rustc_hir_analysis[6239ffc5e5ec24c9]::check_crate::{closure#4}>::{closure#0}
46: 0x777bc73671c1 - rustc_hir_analysis[6239ffc5e5ec24c9]::check_crate
47: 0x777bc735cf15 - rustc_interface[73bd107be0165211]::passes::analysis
48: 0x777bc735cad9 - rustc_query_impl[b034b92d40b1d47d]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b034b92d40b1d47d]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 1usize]>>
49: 0x777bc7e50825 - rustc_query_system[4a94863d7e85f976]::query::plumbing::try_execute_query::<rustc_query_impl[b034b92d40b1d47d]::DynamicConfig<rustc_query_system[4a94863d7e85f976]::query::caches::SingleCache<rustc_middle[e321b4b4f2134162]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[b034b92d40b1d47d]::plumbing::QueryCtxt, false>
50: 0x777bc7e5058f - rustc_query_impl[b034b92d40b1d47d]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
51: 0x777bc7d77e3f - rustc_interface[73bd107be0165211]::interface::run_compiler::<core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>, rustc_driver_impl[6d6094f07793e4a9]::run_compiler::{closure#0}>::{closure#1}
52: 0x777bc7c37e89 - std[e6dd88f179d4d596]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[73bd107be0165211]::util::run_in_thread_with_globals<rustc_interface[73bd107be0165211]::util::run_in_thread_pool_with_globals<rustc_interface[73bd107be0165211]::interface::run_compiler<core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>, rustc_driver_impl[6d6094f07793e4a9]::run_compiler::{closure#0}>::{closure#1}, core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>>::{closure#0}, core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>>
53: 0x777bc7c37c3a - <<std[e6dd88f179d4d596]::thread::Builder>::spawn_unchecked_<rustc_interface[73bd107be0165211]::util::run_in_thread_with_globals<rustc_interface[73bd107be0165211]::util::run_in_thread_pool_with_globals<rustc_interface[73bd107be0165211]::interface::run_compiler<core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>, rustc_driver_impl[6d6094f07793e4a9]::run_compiler::{closure#0}>::{closure#1}, core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>>::{closure#0}, core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[672c7616ff9a88f5]::result::Result<(), rustc_span[31538c27a715cd64]::ErrorGuaranteed>>::{closure#2} as core[672c7616ff9a88f5]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
54: 0x777bc942116b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hcfcb27dcb2ebeeb7
at /rustc/d929a42a664c026167800801b26d734db925314f/library/alloc/src/boxed.rs:2064:9
55: 0x777bc942116b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h7d3cd9c06edd61cc
at /rustc/d929a42a664c026167800801b26d734db925314f/library/alloc/src/boxed.rs:2064:9
56: 0x777bc942116b - std::sys::pal::unix::thread::Thread::new::thread_start::h082ffbd0fcdeae0d
at /rustc/d929a42a664c026167800801b26d734db925314f/library/std/src/sys/pal/unix/thread.rs:108:17
57: 0x777bc24a6ded - <unknown>
58: 0x777bc252a0dc - <unknown>
59: 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 1.81.0-nightly (d929a42a6 2024-06-25) running on x86_64-unknown-linux-gnu
query stack during panic:
#0 [layout_of] computing layout of `test::Superset`
#1 [evaluate_obligation] evaluating trait selection obligation `{type error}: core::mem::transmutability::BikeshedIntrinsicFrom<test::Superset, core::mem::transmutability::Assume { alignment: false, lifetimes: false, safety: false, validity: false }>`
end of query stack
error: aborting due to 9 previous errors; 1 warning emitted
Some errors have detailed explanations: E0124, E0412, E0517, E0601, E0658, E0740.
For more information about an error, try `rustc --explain E0124`.
@rustbot label +F-allow