ICE expect Adt for unnamed field

[gurry]

Code

struct S {
    _: str
}

fn func(a: S)
{
    let _x = a.f;
}

fn main() {}

Meta

rustc --version --verbose:

rustc 1.78.0-dev
binary: rustc
commit-hash: unknown
commit-date: unknown
host: x86_64-pc-windows-msvc
release: 1.78.0-dev
LLVM version: 18.1.0

Error output

error[E0658]: unnamed fields are not yet fully implemented
  --> ../121757-ice-self-is-struct.rs:21:5
   |
21 |     _: str
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable

error: struct with unnamed fields must have `#[repr(C)]` representation
  --> ../121757-ice-self-is-struct.rs:20:1
   |
20 | struct S {
   | ^^^^^^^^ struct `S` defined here
   |
note: unnamed field defined here
  --> ../121757-ice-self-is-struct.rs:21:5
   |
21 |     _: str
   |     ^^^^^^
help: add `#[repr(C)]` to this struct
   |
20 + #[repr(C)]
21 | struct S {
   |

error: unnamed fields can only have struct or union types
  --> ../121757-ice-self-is-struct.rs:21:5
   |
21 |     _: str
   |     ^^^^^^

Backtrace

thread 'rustc' panicked at compiler\rustc_hir_analysis\src\collect.rs:797:49:
expect Adt for unnamed field
stack backtrace:
   0:     0x7ffdd1bed08b - std::backtrace_rs::backtrace::trace_unsynchronized::h43b35a566376d8c0
   1:     0x7ffdd1bb9df6 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h69aa329c1eebdd12
   2:     0x7ffdd1bff5fa - core::fmt::write::h43e911a4c8eeaf29
   3:     0x7ffdd1be8b31 - std::io::Write::write_fmt::h8014a09f9dbe746f
   4:     0x7ffdd1bb9c49 - std::sys_common::backtrace::print::h011c44e7584b6317
   5:     0x7ffdd1bb3283 - std::panicking::default_hook::h180ba89712984d0e
   6:     0x7ffdd1bb2ffa - std::panicking::default_hook::h180ba89712984d0e
   7:     0x7ffd30696e0a - RNvXsL_NtCs6iaOUQgAX4G_5alloc5boxedINtB5_3BoxNCNvCsaaGoLZrJT1T_17rustc_driver_impl16install_ice_hook0EINtNtNtCsjpBzhLK3VS9_4core3ops8function2FnTRDG0_IB1D_TRL1_INtNtNtB1J_5panic10panic_info9PanicInfoL0_EEEp6OutputuNtNtB1J_6marker4SyncNtB3s_4SendEL_RB2z_EE
   8:     0x7ffdd1bb36f6 - std::panicking::rust_panic_with_hook::h56cbb5b6fc35c3d1
   9:     0x7ffdd1bb63d8 - std::sys_common::backtrace::__rust_end_short_backtrace::he5effd4f04252cad
  10:     0x7ffdd1bb62ff - std::sys_common::backtrace::__rust_end_short_backtrace::he5effd4f04252cad
  11:     0x7ffdd1bb3366 - rust_begin_unwind
  12:     0x7ffdd1c30527 - core::panicking::panic_fmt::h26fb43be4a0382ff
  13:     0x7ffdd1c3045c - core::option::expect_failed::h3577c8f3edbefcf8
  14:     0x7ffd3295088c - RINvXs0_NtNtNtCsjpBzhLK3VS9_4core4iter8adapters3mapINtB6_3MapINtNtB8_9enumerate9EnumerateINtNtNtBc_5slice4iter4IterNtNtCsef3NXIzrFT9_12rustc_middle2ty8FieldDefEENCNvMNtCs329P7cL7PzQ_11rustc_index5sliceINtB2E_10IndexSliceNtNtCs3QpSQfzdkb7_12rustc_target3ab
  15:     0x7ffd3284d89c - <rustc_hir_analysis[45b4dac900b2c2ce]::collect::ItemCtxt as rustc_hir_analysis[45b4dac900b2c2ce]::astconv::AstConv>::set_tainted_by_errors
  16:     0x7ffd33a409f1 - rustc_query_impl[41ff65b64ab350b4]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[41ff65b64ab350b4]::query_impl::find_field::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a5e56af6423dad19]::query::erase::Erased<[u8; 4usize]>>
  17:     0x7ffd3398407f - rustc_query_impl[41ff65b64ab350b4]::query_impl::check_unsafety::encode_query_results
  18:     0x7ffd33ae2ef3 - RINvMs2_NtNtCsebAyhQxexiU_3std6thread5localINtB6_8LocalKeyINtNtCsjpBzhLK3VS9_4core4cell4CellPuEE4withNCINvNtNtNtCsef3NXIzrFT9_12rustc_middle2ty7context3tls13enter_contextNCINvNtNtCs1E54DgIQnXd_18rustc_query_system5query8plumbing20execute_job_non_incrINtCs
  19:     0x7ffd33912c3e - RINvNtNtCs1E54DgIQnXd_18rustc_query_system5query8plumbing17try_execute_queryINtCs5FiQgzJqBuW_16rustc_query_impl13DynamicConfigINtNtB4_6caches12DefaultCacheTNtNtCsjXm0eGRgiQS_10rustc_span6def_id5DefIdNtNtB2y_6symbol5IdentEINtNtNtCsef3NXIzrFT9_12rustc_middl
  20:     0x7ffd3398d322 - rustc_query_impl[41ff65b64ab350b4]::query_impl::find_field::get_query_non_incr::__rust_end_short_backtrace
  21:     0x7ffd325bd587 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_for_missing_semi
  22:     0x7ffd3262b252 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_expr_kind
  23:     0x7ffd325b58d7 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_expr_coercible_to_type
  24:     0x7ffd326292be - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_expr_with_expectation
  25:     0x7ffd325d74df - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_decl_initializer
  26:     0x7ffd325d7718 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_decl_initializer
  27:     0x7ffd325d7a95 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_stmt
  28:     0x7ffd326f0cf2 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::with_breakable_ctxt::<<rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_block_with_expected::{closure#0}, ()>
  29:     0x7ffd325d7d20 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_block_no_value
  30:     0x7ffd32629d52 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_expr_kind
  31:     0x7ffd325b58d7 - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_expr_coercible_to_type
  32:     0x7ffd326292be - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_expr_with_expectation
  33:     0x7ffd325b6e8c - <rustc_hir_typeck[40cfaf708e23f80b]::fn_ctxt::FnCtxt>::check_return_expr
  34:     0x7ffd327aab3c - rustc_hir_typeck[40cfaf708e23f80b]::check::check_fn
  35:     0x7ffd3268eaf2 - rustc_hir_typeck[40cfaf708e23f80b]::typeck_with_fallback::<rustc_hir_typeck[40cfaf708e23f80b]::inspect_typeck::{closure#0}>        
  36:     0x7ffd3259a33e - rustc_hir_typeck[40cfaf708e23f80b]::primary_body_of
  37:     0x7ffd33a5bd2d - rustc_query_impl[41ff65b64ab350b4]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[41ff65b64ab350b4]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a5e56af6423dad19]::query::erase::Erased<[u8; 8usize]>>
  38:     0x7ffd339605de - rustc_query_impl[41ff65b64ab350b4]::query_impl::promoted_mir::encode_query_results
  39:     0x7ffd33ae2a44 - RINvMs2_NtNtCsebAyhQxexiU_3std6thread5localINtB6_8LocalKeyINtNtCsjpBzhLK3VS9_4core4cell4CellPuEE4withNCINvNtNtNtCsef3NXIzrFT9_12rustc_middle2ty7context3tls13enter_contextNCINvNtNtCs1E54DgIQnXd_18rustc_query_system5query8plumbing20execute_job_non_incrINtCs
  40:     0x7ffd3392f122 - RINvNtNtCs1E54DgIQnXd_18rustc_query_system5query8plumbing17try_execute_queryINtCs5FiQgzJqBuW_16rustc_query_impl13DynamicConfigINtNtB4_6caches8VecCacheNtNtCsjXm0eGRgiQS_10rustc_span6def_id10LocalDefIdINtNtNtCsef3NXIzrFT9_12rustc_middle5query5erase6ErasedAh
  41:     0x7ffd33960fe3 - rustc_query_impl[41ff65b64ab350b4]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
  42:     0x7ffd32a2c103 - RINvNtCsebAyhQxexiU_3std9panicking3tryuINtNtNtCsjpBzhLK3VS9_4core5panic11unwind_safe16AssertUnwindSafeNCNCNCINvNtNtNtCs8bTriOcSdES_21rustc_data_structures4sync8parallel7enabled15par_for_each_inRNtNtCsjXm0eGRgiQS_10rustc_span6def_id10LocalDefIdRSB36_NCINvM
  43:     0x7ffd32a2b880 - RINvNtCsebAyhQxexiU_3std9panicking3tryuINtNtNtCsjpBzhLK3VS9_4core5panic11unwind_safe16AssertUnwindSafeNCNCNCINvNtNtNtCs8bTriOcSdES_21rustc_data_structures4sync8parallel7enabled15par_for_each_inRNtNtCsjXm0eGRgiQS_10rustc_span6def_id10LocalDefIdRSB36_NCINvM
  44:     0x7ffd329fdf32 - RINvMNtNtCs8bTriOcSdES_21rustc_data_structures4sync8parallelNtB3_13ParallelGuard3runuNCNCNCINvNtB3_7enabled15par_for_each_inRNtNtCsjXm0eGRgiQS_10rustc_span6def_id10LocalDefIdRSB1Z_NCINvMs1_NtNtCsef3NXIzrFT9_12rustc_middle3hir3mapNtB31_3Map15par_body_owner
  45:     0x7ffd328e9ca2 - RINvNtNtNtCs8bTriOcSdES_21rustc_data_structures4sync8parallel7enabled15par_for_each_inRNtNtCsjXm0eGRgiQS_10rustc_span6def_id10LocalDefIdRSB1n_NCINvMs1_NtNtCsef3NXIzrFT9_12rustc_middle3hir3mapNtB2p_3Map15par_body_ownersNCNvCs5Z2QjRJ4hA0_18rustc_hir_analysi
  46:     0x7ffd328196c9 - rustc_hir_analysis[45b4dac900b2c2ce]::check_crate
  47:     0x7ffd308032f9 - rustc_interface[3eeae0d001a4b635]::passes::analysis
  48:     0x7ffd33a5c15c - rustc_query_impl[41ff65b64ab350b4]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[41ff65b64ab350b4]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a5e56af6423dad19]::query::erase::Erased<[u8; 1usize]>>
  49:     0x7ffd3399955b - rustc_query_impl[41ff65b64ab350b4]::query_impl::instantiate_and_check_impossible_predicates::alloc_self_profile_query_strings      
  50:     0x7ffd33ae16bd - RINvMs2_NtNtCsebAyhQxexiU_3std6thread5localINtB6_8LocalKeyINtNtCsjpBzhLK3VS9_4core4cell4CellPuEE4withNCINvNtNtNtCsef3NXIzrFT9_12rustc_middle2ty7context3tls13enter_contextNCINvNtNtCs1E54DgIQnXd_18rustc_query_system5query8plumbing20execute_job_non_incrINtCs
  51:     0x7ffd338b2f78 - RINvNtNtCs1E54DgIQnXd_18rustc_query_system5query8plumbing17try_execute_queryINtCs5FiQgzJqBuW_16rustc_query_impl13DynamicConfigINtNtB4_6caches11SingleCacheINtNtNtCsef3NXIzrFT9_12rustc_middle5query5erase6ErasedAhj1_EEKb0_KB3s_KB3s_ENtNtB1f_8plumbing9QueryCt
  52:     0x7ffd33954ff1 - rustc_query_impl[41ff65b64ab350b4]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  53:     0x7ffd306cd676 - RINvMs2_NtNtCsebAyhQxexiU_3std6thread5localINtB6_8LocalKeyINtNtCsjpBzhLK3VS9_4core4cell4CellPuEE4withNCINvNtNtNtCsef3NXIzrFT9_12rustc_middle2ty7context3tls13enter_contextNCINvMs9_B1I_NtB1I_10GlobalCtxt5enterNCNCNCNvCsaaGoLZrJT1T_17rustc_driver_impl12run_c
  54:     0x7ffd306c05ed - <rustc_middle[a5e56af6423dad19]::ty::context::GlobalCtxt>::enter::<rustc_driver_impl[767bba05edafb3bb]::run_compiler::{closure#0}::{closure#1}::{closure#3}, core[e21d7e5d074c18ab]::result::Result<(), rustc_span[e874984deae97828]::ErrorGuaranteed>>
  55:     0x7ffd30687b5d - RINvMs5_NtCs5oUjEq15j35_15rustc_interface7queriesNtNtB8_9interface8Compiler5enterNCNCNvCsaaGoLZrJT1T_17rustc_driver_impl12run_compiler0s_0INtNtCsjpBzhLK3VS9_4core6result6ResultINtNtB2h_6option6OptionNtB6_6LinkerENtCsjXm0eGRgiQS_10rustc_span15ErrorGuarante
  56:     0x7ffd306a635b - rustc_span[e874984deae97828]::set_source_map::<core[e21d7e5d074c18ab]::result::Result<(), rustc_span[e874984deae97828]::ErrorGuaranteed>, rustc_interface[3eeae0d001a4b635]::interface::run_compiler<core[e21d7e5d074c18ab]::result::Result<(), rustc_span[e874984deae97828]::ErrorGuaranteed>, rustc_driver_impl[767bba05edafb3bb]::run_compiler::{closure#0}>::{closure#0}::{closure#0}>
  57:     0x7ffd306cf97b - RINvMs_CsgVCJzdmiPiq_10scoped_tlsINtB5_9ScopedKeyNtCsjXm0eGRgiQS_10rustc_span14SessionGlobalsE3setNCINvNtCs5oUjEq15j35_15rustc_interface4util31run_in_thread_pool_with_globalsNCINvNtB1F_9interface12run_compilerINtNtCsjpBzhLK3VS9_4core6result6ResultuNtBN_15
  58:     0x7ffd306a6bf1 - RINvCsjXm0eGRgiQS_10rustc_span27create_session_globals_thenINtNtCsjpBzhLK3VS9_4core6result6ResultuNtB2_15ErrorGuaranteedENCINvNtCs5oUjEq15j35_15rustc_interface4util31run_in_thread_pool_with_globalsNCINvNtB22_9interface12run_compilerBV_NCNvCsaaGoLZrJT1T_17
  59:     0x7ffd306c8c28 - RINvNtNtCsebAyhQxexiU_3std10sys_common9backtrace28___rust_begin_short_backtraceNCNCINvNtCs5oUjEq15j35_15rustc_interface4util26run_in_thread_with_globalsNCINvB1m_31run_in_thread_pool_with_globalsNCINvNtB1o_9interface12run_compilerINtNtCsjpBzhLK3VS9_4core6r
  60:     0x7ffd3069e909 - RINvNtCsebAyhQxexiU_3std9panicking3tryINtNtCsjpBzhLK3VS9_4core6result6ResultuNtCsjXm0eGRgiQS_10rustc_span15ErrorGuaranteedEINtNtNtBF_5panic11unwind_safe16AssertUnwindSafeNCNCINvMNtB4_6threadNtB2Q_7Builder16spawn_unchecked_NCNCINvNtCs5oUjEq15j35_15rustc_in
  61:     0x7ffd306cb7d0 - RINvNtCsebAyhQxexiU_3std6thread5spawnNCNCINvNtCs5oUjEq15j35_15rustc_interface4util31run_in_thread_pool_with_globalsNCINvNtBI_9interface12run_compilerINtNtCsjpBzhLK3VS9_4core6result6ResultuNtCsjXm0eGRgiQS_10rustc_span15ErrorGuaranteedENCNvCsaaGoLZrJT1T_17r
  62:     0x7ffdd1be939b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h374ce232189b6f7d
  63:     0x7ffdd1beee03 - std::sys::pal::windows::thread::Thread::new::h61d19b62b0a4eb25
  64:     0x7ffe7668257d - BaseThreadInitThunk
  65:     0x7ffe778eaa68 - RtlUserThreadStart

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 attach the file at `D:\Projects\rust_dev\rustc\rust2\rustc-ice-2024-02-29T13_21_44-21284.txt` to your bug report

query stack during panic:
#0 [find_field] find the index of maybe nested field `f` in `S`
#1 [typeck] type-checking `func`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errorsthread 'rustc' panicked at compiler\rustc_hir_analysis\src\collect.rs:797:49:

[gurry]

LIkely related to #121757

[matthiaskrgr]

duplicate of #121263 ?

[compiler-errors]

Yes, duplicate