ICE in adt_const_params: panicked at 'const parameter types cannot be generic'

[asquared31415]

Code

#![allow(incomplete_features)]
#![feature(adt_const_params)]

struct LifetimeGeneric<'a>(&'a ());

struct UwU<'b, const T: LifetimeGeneric>(&'b ());

playground

LifetimeGeneric and UwU need to be generic over a lifetime specifically, removing either lifetime does not ICE.

Meta

rustc --version --verbose:

rustc 1.70.0-nightly (900c35403 2023-03-08)
binary: rustc
commit-hash: 900c3540378c8422b8087ffa3db60fa6c8abfcad
commit-date: 2023-03-08
host: x86_64-unknown-linux-gnu
release: 1.70.0-nightly
LLVM version: 15.0.7

Backtrace

error[[E0106]](https://doc.rust-lang.org/nightly/error_codes/E0106.html): missing lifetime specifier
 --> src/lib.rs:6:25
  |
6 | struct UwU<'b, const T: LifetimeGeneric>(&'b ());
  |                         ^^^^^^^^^^^^^^^ expected named lifetime parameter
  |
help: consider using the `'b` lifetime
  |
6 | struct UwU<'b, const T: LifetimeGeneric<'b>>(&'b ());
  |                                        ++++

thread 'rustc' panicked at 'const parameter types cannot be generic', compiler/rustc_middle/src/ty/context.rs:2029:26
stack backtrace:
   0:     0x7fcb6e18353a - std::backtrace_rs::backtrace::libunwind::trace::h5499f6e9ee8d39f8
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7fcb6e18353a - std::backtrace_rs::backtrace::trace_unsynchronized::h7278d8915e5a8a4f
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fcb6e18353a - std::sys_common::backtrace::_print_fmt::h0c7e844ccbe54001
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7fcb6e18353a - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h76f2d4fdd5e6ad12
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7fcb6e1e6cee - core::fmt::write::h1775f2c88ef0e3b9
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/core/src/fmt/mod.rs:1232:17
   5:     0x7fcb6e1764e5 - std::io::Write::write_fmt::hfa496b0ed0f58ff3
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/io/mod.rs:1684:15
   6:     0x7fcb6e183305 - std::sys_common::backtrace::_print::h995e9f70ef8cb7a5
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/sys_common/backtrace.rs:47:5
   7:     0x7fcb6e183305 - std::sys_common::backtrace::print::he938621c452cca4c
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/sys_common/backtrace.rs:34:9
   8:     0x7fcb6e18607f - std::panicking::default_hook::{{closure}}::h54a42fdbf61bd63c
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/panicking.rs:271:22
   9:     0x7fcb6e185dbb - std::panicking::default_hook::h237f087925386eb9
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/panicking.rs:290:9
  10:     0x7fcb714756c5 - <rustc_driver_impl[37bd08e570b8de33]::DEFAULT_HOOK::{closure#0}::{closure#0} as core[9f74edcc8a2533f5]::ops::function::FnOnce<(&core[9f74edcc8a2533f5]::panic::panic_info::PanicInfo,)>>::call_once::{shim:vtable#0}
  11:     0x7fcb6e1868bd - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h86b8a5cdb22895d8
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/alloc/src/boxed.rs:2001:9
  12:     0x7fcb6e1868bd - std::panicking::rust_panic_with_hook::h3b3e70d6d2eb55f8
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/panicking.rs:696:13
  13:     0x7fcb6e186639 - std::panicking::begin_panic_handler::{{closure}}::hdb26ba8feb23c2d0
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/panicking.rs:583:13
  14:     0x7fcb6e1839a6 - std::sys_common::backtrace::__rust_end_short_backtrace::heb4e04cb16e3e639
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/sys_common/backtrace.rs:150:18
  15:     0x7fcb6e186342 - rust_begin_unwind
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/panicking.rs:579:5
  16:     0x7fcb6e1e3043 - core::panicking::panic_fmt::h1aa26efd95b582e6
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/core/src/panicking.rs:64:14
  17:     0x7fcb6e1e31b1 - core::panicking::panic_display::h8b07ac88322081f4
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/core/src/panicking.rs:147:5
  18:     0x7fcb6e1e315b - core::panicking::panic_str::h834cb14285912af4
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/core/src/panicking.rs:131:5
  19:     0x7fcb6e1e2dc6 - core::option::expect_failed::hf9b4e924d89d67b9
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/core/src/option.rs:2045:5
  20:     0x7fcb6fcad83d - <rustc_middle[d952a4eb3363976b]::ty::list::List<rustc_middle[d952a4eb3363976b]::ty::subst::GenericArg>>::fill_item::<<rustc_middle[d952a4eb3363976b]::ty::list::List<rustc_middle[d952a4eb3363976b]::ty::subst::GenericArg>>::identity_for_item::{closure#0}>
  21:     0x7fcb6fcac362 - <rustc_middle[d952a4eb3363976b]::ty::list::List<rustc_middle[d952a4eb3363976b]::ty::subst::GenericArg>>::identity_for_item
  22:     0x7fcb7098c871 - rustc_hir_analysis[db450ef6184d9cb6]::collect::type_of::type_of
  23:     0x7fcb6fe82d80 - rustc_query_system[bc9882aaabdaeb26]::query::plumbing::try_execute_query::<rustc_query_impl[d542d75c076a29bb]::queries::type_of, rustc_query_impl[d542d75c076a29bb]::plumbing::QueryCtxt>
  24:     0x7fcb6fe8170c - <rustc_query_impl[d542d75c076a29bb]::Queries as rustc_middle[d952a4eb3363976b]::ty::query::QueryEngine>::type_of
  25:     0x7fcb6fcf94c6 - <rustc_hir_analysis[db450ef6184d9cb6]::collect::CollectItemTypesVisitor as rustc_hir[829d2a01d5dbcc01]::intravisit::Visitor>::visit_item
  26:     0x7fcb6fcf7b86 - <rustc_middle[d952a4eb3363976b]::hir::map::Map>::visit_item_likes_in_module::<rustc_hir_analysis[db450ef6184d9cb6]::collect::CollectItemTypesVisitor>
  27:     0x7fcb6fcf7a9c - rustc_hir_analysis[db450ef6184d9cb6]::collect::collect_mod_item_types
  28:     0x7fcb70ae0c05 - rustc_query_system[bc9882aaabdaeb26]::query::plumbing::try_execute_query::<rustc_query_impl[d542d75c076a29bb]::queries::collect_mod_item_types, rustc_query_impl[d542d75c076a29bb]::plumbing::QueryCtxt>
  29:     0x7fcb70ae079a - <rustc_query_impl[d542d75c076a29bb]::Queries as rustc_middle[d952a4eb3363976b]::ty::query::QueryEngine>::collect_mod_item_types
  30:     0x7fcb6f8ee7ef - <rustc_middle[d952a4eb3363976b]::hir::map::Map>::for_each_module::<rustc_hir_analysis[db450ef6184d9cb6]::check_crate::{closure#0}::{closure#0}::{closure#0}>
  31:     0x7fcb6f8ee3d8 - <rustc_session[ba04d21bdf852ac2]::session::Session>::track_errors::<rustc_hir_analysis[db450ef6184d9cb6]::check_crate::{closure#0}, ()>
  32:     0x7fcb6f8eb8f2 - rustc_hir_analysis[db450ef6184d9cb6]::check_crate
  33:     0x7fcb6f8e18e2 - rustc_interface[b840461aee9fca96]::passes::analysis
  34:     0x7fcb70c9d45d - rustc_query_system[bc9882aaabdaeb26]::query::plumbing::try_execute_query::<rustc_query_impl[d542d75c076a29bb]::queries::analysis, rustc_query_impl[d542d75c076a29bb]::plumbing::QueryCtxt>
  35:     0x7fcb70c9d15f - <rustc_query_impl[d542d75c076a29bb]::Queries as rustc_middle[d952a4eb3363976b]::ty::query::QueryEngine>::analysis
  36:     0x7fcb70adb0d6 - <rustc_middle[d952a4eb3363976b]::ty::context::GlobalCtxt>::enter::<rustc_driver_impl[37bd08e570b8de33]::run_compiler::{closure#1}::{closure#2}::{closure#4}, core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>>
  37:     0x7fcb706cb858 - rustc_span[312e5fbb5d1460ce]::with_source_map::<core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>, rustc_interface[b840461aee9fca96]::interface::run_compiler<core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>, rustc_driver_impl[37bd08e570b8de33]::run_compiler::{closure#1}>::{closure#0}::{closure#0}>
  38:     0x7fcb706c2fec - std[76763ff83cd4f414]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[b840461aee9fca96]::util::run_in_thread_pool_with_globals<rustc_interface[b840461aee9fca96]::interface::run_compiler<core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>, rustc_driver_impl[37bd08e570b8de33]::run_compiler::{closure#1}>::{closure#0}, core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>>
  39:     0x7fcb706c2a1a - <<std[76763ff83cd4f414]::thread::Builder>::spawn_unchecked_<rustc_interface[b840461aee9fca96]::util::run_in_thread_pool_with_globals<rustc_interface[b840461aee9fca96]::interface::run_compiler<core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>, rustc_driver_impl[37bd08e570b8de33]::run_compiler::{closure#1}>::{closure#0}, core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[9f74edcc8a2533f5]::result::Result<(), rustc_span[312e5fbb5d1460ce]::ErrorGuaranteed>>::{closure#1} as core[9f74edcc8a2533f5]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  40:     0x7fcb6e1907b3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h2d50a0adfdb2874f
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/alloc/src/boxed.rs:1987:9
  41:     0x7fcb6e1907b3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h7afed2ea646a4458
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/alloc/src/boxed.rs:1987:9
  42:     0x7fcb6e1907b3 - std::sys::unix::thread::Thread::new::thread_start::h950100cbea36de7e
                               at /rustc/900c3540378c8422b8087ffa3db60fa6c8abfcad/library/std/src/sys/unix/thread.rs:108:17
  43:     0x7fcb6e055609 - start_thread
  44:     0x7fcb6df78133 - clone
  45:                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 1.70.0-nightly (900c35403 2023-03-08) running on x86_64-unknown-linux-gnu

note: compiler flags: --crate-type lib -C embed-bitcode=no -C codegen-units=1 -C debuginfo=2

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
#0 [type_of] computing type of `UwU`
#1 [collect_mod_item_types] collecting item types in top-level module
#2 [analysis] running analysis passes on this crate
end of query stack
For more information about this error, try `rustc --explain E0106`.
error: could not compile `playground` (lib) due to previous error

[langston-barrett]

@rustbot label +S-bug-has-mcve

[langston-barrett]

Triaged with Icemelter. Steps performed:

• Reproduced: ✅
• Formatted: ✅ No change, already formatted
• Reduced: ❌
• Bisected: ✅

Regression in nightly-2023-02-18

searched nightlies: from nightly-2023-02-17 to nightly-2023-03-18
regressed nightly: nightly-2023-02-18
searched commit range: 9a7cc6c...9aa5c24
regressed commit: 9556b56

bisected with cargo-bisect-rustc v0.6.5

Host triple: x86_64-unknown-linux-gnu
Reproduce with:

cargo bisect-rustc /tmp/bisect-jga8wm.sh --preserve 

Details

rustc version:

rustc 1.70.0-nightly (13afbdaa0 2023-03-17)
binary: rustc
commit-hash: 13afbdaa0655dda23d7129e59ac48f1ec88b2084
commit-date: 2023-03-17
host: x86_64-unknown-linux-gnu
release: 1.70.0-nightly
LLVM version: 15.0.7

Icemelter version: v0.2.0

Icemelter command line:

'icemelter' '--markdown' '--bisect' 'ice.rs' '--' 'rustc' '+nightly'

@rustbot label +S-bug-has-mcve

Do you have feedback about this report? Please file an issue!

[JohnTitor]

Fixed on the latest nightly, marking as E-needs-test (or, feel free to close if we have a sufficient regression test)
@rustbot labels: +E-needs-test

[jruderman]

Fixed in nightly-2023-08-10 with rollup 19a647d. I'm guessing #114606 fixed this.

[JohnTitor]

Thank you for bisecting! The regression test there should cover this issue's case, closing.