error[E0658]: `impl Trait` in type aliases is unstable --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:3:18 | 3 | type Alias<'a> = impl T; | ^^^^^^ | = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable = note: this compiler was built on 2024-02-21; consider upgrading it if it is out of date error: item constrains opaque type that is not in its signature --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:11:20 | 11 | with_positive(|&n| ()); | ^^ | = note: this item must mention the opaque type in its signature in order to be able to register hidden types note: this item must mention the opaque type in its signature in order to be able to register hidden types --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:10:4 | 10 | fn main() { | ^^^^ warning: unused variable: `n` --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:11:21 | 11 | with_positive(|&n| ()); | ^ help: if this is intentional, prefix it with an underscore: `_n` | = note: `#[warn(unused_variables)]` on by default error[E0507]: cannot move out of a shared reference --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:11:20 | 11 | with_positive(|&n| ()); | ^- | | | data moved here | move occurs because `n` has type `S`, which does not implement the `Copy` trait | help: consider removing the borrow | 11 - with_positive(|&n| ()); 11 + with_positive(|n| ()); | error: item constrains opaque type that is not in its signature --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:11:20 | 11 | with_positive(|&n| ()); | ^^ | = note: this item must mention the opaque type in its signature in order to be able to register hidden types note: this item must mention the opaque type in its signature in order to be able to register hidden types --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:11:19 | 11 | with_positive(|&n| ()); | ^^^^ warning: unused variable: `fun` --> /tmp/icemaker_global_tempdir.F5838RU6DQwp/rustc_testrunner_tmpdir_reporting.lgnzWyLkPTPL/mvce.rs:8:18 | 8 | fn with_positive(fun: impl Fn(Alias<'_>)) {} | ^^^ help: if this is intentional, prefix it with an underscore: `_fun` thread 'rustc' panicked at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/compiler/rustc_mir_dataflow/src/un_derefer.rs:67:20: index out of bounds: the len is 0 but the index is 0 stack backtrace: 0: 0x7f603d823af6 - std::backtrace_rs::backtrace::libunwind::trace::hbec2edc838b433e2 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5 1: 0x7f603d823af6 - std::backtrace_rs::backtrace::trace_unsynchronized::h88c30257ee0dd166 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5 2: 0x7f603d823af6 - std::sys_common::backtrace::_print_fmt::h9176654d509e3088 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/sys_common/backtrace.rs:68:5 3: 0x7f603d823af6 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h671feaee1776bf19 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/sys_common/backtrace.rs:44:22 4: 0x7f603d874a7c - core::fmt::rt::Argument::fmt::h59605c83ae32d935 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/core/src/fmt/rt.rs:142:9 5: 0x7f603d874a7c - core::fmt::write::hf7af8dfcfd20db5b at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/core/src/fmt/mod.rs:1120:17 6: 0x7f603d8184bf - std::io::Write::write_fmt::h92a5dbf489025e71 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/io/mod.rs:1846:15 7: 0x7f603d8238a4 - std::sys_common::backtrace::_print::h00080302d23998ae at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/sys_common/backtrace.rs:47:5 8: 0x7f603d8238a4 - std::sys_common::backtrace::print::h6b23124445400245 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/sys_common/backtrace.rs:34:9 9: 0x7f603d8265eb - std::panicking::default_hook::{{closure}}::hd67b2f9d36675a28 10: 0x7f603d826339 - std::panicking::default_hook::h10a39ef11c714e42 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/panicking.rs:292:9 11: 0x7f603a47a94c - std[5a8e7f94216a9138]::panicking::update_hook::<alloc[e14ab1f516d287ab]::boxed::Box<rustc_driver_impl[e279e4f1fedd9109]::install_ice_hook::{closure#0}>>::{closure#0} 12: 0x7f603d826d50 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h37ba37dc48823c1d at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/alloc/src/boxed.rs:2030:9 13: 0x7f603d826d50 - std::panicking::rust_panic_with_hook::he3e3bc7c345bf54b at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/panicking.rs:786:13 14: 0x7f603d826a92 - std::panicking::begin_panic_handler::{{closure}}::h4bfbc62f377d59e6 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/panicking.rs:660:13 15: 0x7f603d823fd6 - std::sys_common::backtrace::__rust_end_short_backtrace::hc8487cf1bc04a693 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/sys_common/backtrace.rs:171:18 16: 0x7f603d8267c4 - rust_begin_unwind at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/panicking.rs:648:5 17: 0x7f603d870f95 - core::panicking::panic_fmt::h88277cce839da186 at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/core/src/panicking.rs:72:14 18: 0x7f603d8711e2 - core::panicking::panic_bounds_check::h7889403d641fd53a at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/core/src/panicking.rs:208:5 19: 0x7f603898e24a - <rustc_mir_dataflow[9dbea5a14cdf9346]::move_paths::builder::Gatherer<<rustc_mir_transform[2f80b166b66099ac]::elaborate_drops::ElaborateDrops as rustc_middle[446dd094ad85939e]::mir::MirPass>::run_pass::{closure#0}>>::gather_move 20: 0x7f6038973697 - <rustc_mir_transform[2f80b166b66099ac]::elaborate_drops::ElaborateDrops as rustc_middle[446dd094ad85939e]::mir::MirPass>::run_pass 21: 0x7f603b812689 - rustc_mir_transform[2f80b166b66099ac]::pass_manager::run_passes_inner 22: 0x7f603ba42806 - rustc_mir_transform[2f80b166b66099ac]::mir_drops_elaborated_and_const_checked 23: 0x7f603ba4213d - rustc_query_impl[9d4c51777e2bb749]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[9d4c51777e2bb749]::query_impl::mir_drops_elaborated_and_const_checked::dynamic_query::{closure#2}::{closure#0}, rustc_middle[446dd094ad85939e]::query::erase::Erased<[u8; 8usize]>> 24: 0x7f603b9098b0 - rustc_query_system[9b2ccfe41ae3bb1b]::query::plumbing::try_execute_query::<rustc_query_impl[9d4c51777e2bb749]::DynamicConfig<rustc_query_system[9b2ccfe41ae3bb1b]::query::caches::VecCache<rustc_span[adb133ac03280fc1]::def_id::LocalDefId, rustc_middle[446dd094ad85939e]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[9d4c51777e2bb749]::plumbing::QueryCtxt, false> 25: 0x7f603b90919e - rustc_query_impl[9d4c51777e2bb749]::query_impl::mir_drops_elaborated_and_const_checked::get_query_non_incr::__rust_end_short_backtrace 26: 0x7f603c2a333f - rustc_interface[7ca501d7f8f3a34f]::passes::analysis 27: 0x7f603c2a2a29 - rustc_query_impl[9d4c51777e2bb749]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[9d4c51777e2bb749]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[446dd094ad85939e]::query::erase::Erased<[u8; 1usize]>> 28: 0x7f603c53d4a5 - rustc_query_system[9b2ccfe41ae3bb1b]::query::plumbing::try_execute_query::<rustc_query_impl[9d4c51777e2bb749]::DynamicConfig<rustc_query_system[9b2ccfe41ae3bb1b]::query::caches::SingleCache<rustc_middle[446dd094ad85939e]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[9d4c51777e2bb749]::plumbing::QueryCtxt, false> 29: 0x7f603c53d209 - rustc_query_impl[9d4c51777e2bb749]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace 30: 0x7f603c54c719 - rustc_interface[7ca501d7f8f3a34f]::interface::run_compiler::<core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>, rustc_driver_impl[e279e4f1fedd9109]::run_compiler::{closure#0}>::{closure#0} 31: 0x7f603c7be705 - std[5a8e7f94216a9138]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[7ca501d7f8f3a34f]::util::run_in_thread_with_globals<rustc_interface[7ca501d7f8f3a34f]::util::run_in_thread_pool_with_globals<rustc_interface[7ca501d7f8f3a34f]::interface::run_compiler<core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>, rustc_driver_impl[e279e4f1fedd9109]::run_compiler::{closure#0}>::{closure#0}, core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>>::{closure#0}, core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>> 32: 0x7f603c7be532 - <<std[5a8e7f94216a9138]::thread::Builder>::spawn_unchecked_<rustc_interface[7ca501d7f8f3a34f]::util::run_in_thread_with_globals<rustc_interface[7ca501d7f8f3a34f]::util::run_in_thread_pool_with_globals<rustc_interface[7ca501d7f8f3a34f]::interface::run_compiler<core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>, rustc_driver_impl[e279e4f1fedd9109]::run_compiler::{closure#0}>::{closure#0}, core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>>::{closure#0}, core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[85b4fd477ce5bb21]::result::Result<(), rustc_span[adb133ac03280fc1]::ErrorGuaranteed>>::{closure#1} as core[85b4fd477ce5bb21]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} 33: 0x7f603d830725 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h1bff3efb61c3fa6b at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/alloc/src/boxed.rs:2016:9 34: 0x7f603d830725 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h83141cf549dced8a at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/alloc/src/boxed.rs:2016:9 35: 0x7f603d830725 - std::sys::pal::unix::thread::Thread::new::thread_start::hbe9287fdd7c325bc at /rustc/f8131a48a46ac3bc8a3d0fe0477055b132cffdc3/library/std/src/sys/pal/unix/thread.rs:108:17 36: 0x7f60374aa9eb - <unknown> 37: 0x7f603752e7cc - <unknown> 38: 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: rustc 1.78.0-nightly (f8131a48a 2024-02-21) running on x86_64-unknown-linux-gnu query stack during panic: #0 [mir_drops_elaborated_and_const_checked] elaborating drops for `main::{closure#0}` #1 [analysis] running analysis passes on this crate end of query stack error: aborting due to 4 previous errors; 2 warnings emitted Some errors have detailed explanations: E0507, E0658. For more information about an error, try `rustc --explain E0507`.