internal compiler error for type parameter out of range when substituting

[iamanonymouscs]

Code

#![feature(generic_const_exprs)]

struct A<const B: str = 1, C>;

fn main() {}

Meta

rustc --version --verbose:

rustc 1.73.0-nightly (db7ff98a7 2023-07-31)
binary: rustc
commit-hash: db7ff98a72f3e742b641f9cb16d0e8c285e87e9b
commit-date: 2023-07-31
host: x86_64-unknown-linux-gnu
release: 1.73.0-nightly
LLVM version: 16.0.5

Error output

error: generic parameters with a default must be trailing
 --> 1.rs:3:16
  |
3 | struct A<const B: str = 1, C>;
  |                ^

warning: the feature `generic_const_exprs` is incomplete and may not be safe to use and/or cause compiler crashes
 --> 1.rs:1:12
  |
1 | #![feature(generic_const_exprs)]
  |            ^^^^^^^^^^^^^^^^^^^
  |
  = note: see issue #76560 <https://github.com/rust-lang/rust/issues/76560> for more information
  = note: `#[warn(incomplete_features)]` on by default

error: internal compiler error: compiler/rustc_middle/src/ty/generic_args.rs:900:9: type parameter `C/#1` (C/1) out of range when substituting, args=[]

Backtrace

``` thread 'rustc' panicked at 'Box', /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/compiler/rustc_errors/src/lib.rs:1645:9 stack backtrace: 0: 0x7f7f59d564bc - std::backtrace_rs::backtrace::libunwind::trace::h00560e9152510f67 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5 1: 0x7f7f59d564bc - std::backtrace_rs::backtrace::trace_unsynchronized::h0f27c3665dd0a867 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5 2: 0x7f7f59d564bc - std::sys_common::backtrace::_print_fmt::h5dba0ff3e06fa698 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/sys_common/backtrace.rs:67:5 3: 0x7f7f59d564bc - ::fmt::h4debeea1996f535b at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/sys_common/backtrace.rs:44:22 4: 0x7f7f59dbcbac - core::fmt::rt::Argument::fmt::h1e53d9bbf5a265dd at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/core/src/fmt/rt.rs:138:9 5: 0x7f7f59dbcbac - core::fmt::write::hcb86202702aeaf68 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/core/src/fmt/mod.rs:1094:21 6: 0x7f7f59d48b1e - std::io::Write::write_fmt::h6b056feb2ab827f8 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/io/mod.rs:1714:15 7: 0x7f7f59d562a5 - std::sys_common::backtrace::_print::h63c494f55c85c02e at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/sys_common/backtrace.rs:47:5 8: 0x7f7f59d562a5 - std::sys_common::backtrace::print::h0d84953923cd4383 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/sys_common/backtrace.rs:34:9 9: 0x7f7f59d593fa - std::panicking::panic_hook_with_disk_dump::{{closure}}::h0ded106e3e100970 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/panicking.rs:278:22 10: 0x7f7f59d59093 - std::panicking::panic_hook_with_disk_dump::h80545efc2b457190 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/panicking.rs:312:9 11: 0x7f7f58b272e9 - rustc_driver_impl[953ac255d00f3c7f]::install_ice_hook::{closure#0} 12: 0x7f7f59d59ca0 - as core::ops::function::Fn>::call::h005d394de554c94e at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/alloc/src/boxed.rs:2021:9 13: 0x7f7f59d59ca0 - std::panicking::rust_panic_with_hook::ha35d072680b6716b at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/panicking.rs:733:13 14: 0x7f7f59099711 - std[cfe24ee53075a1e5]::panicking::begin_panic::::{closure#0} 15: 0x7f7f59096cc6 - std[cfe24ee53075a1e5]::sys_common::backtrace::__rust_end_short_backtrace::::{closure#0}, !> 16: 0x7f7f590de776 - std[cfe24ee53075a1e5]::panicking::begin_panic:: 17: 0x7f7f590a0594 - ::bug:: 18: 0x7f7f590a0426 - ::bug:: 19: 0x7f7f5912dcec - rustc_middle[23eac342ec155d27]::util::bug::opt_span_bug_fmt::::{closure#0} 20: 0x7f7f5912caea - rustc_middle[23eac342ec155d27]::ty::context::tls::with_opt::::{closure#0}, !>::{closure#0} 21: 0x7f7f5912cab8 - rustc_middle[23eac342ec155d27]::ty::context::tls::with_context_opt::::{closure#0}, !>::{closure#0}, !> 22: 0x7f7f5742fbc0 - rustc_middle[23eac342ec155d27]::util::bug::bug_fmt 23: 0x7f7f590d76b5 - ::type_param_out_of_range 24: 0x7f7f56b7e8f6 - as alloc[9d71a00e6f43b08]::vec::spec_extend::SpecExtend, ::instantiate_into::{closure#0}>>>::spec_extend 25: 0x7f7f56b7bc5c - ::instantiate_into 26: 0x7f7f5713d86a - ::nominal_obligations_inner 27: 0x7f7f57137345 - ::compute 28: 0x7f7f56e9a3ae - ::process_obligation 29: 0x7f7f56e963f4 - >::process_obligations:: 30: 0x7f7f5724d44f - ::select_all_or_error 31: 0x7f7f57548bdb - rustc_hir_analysis[2c6ebfa0ec54105a]::check::wfcheck::check_type_defn 32: 0x7f7f57526568 - rustc_hir_analysis[2c6ebfa0ec54105a]::check::wfcheck::check_well_formed 33: 0x7f7f56b2951c - rustc_query_impl[c1c3c70d39a20423]::plumbing::__rust_begin_short_backtrace::> 34: 0x7f7f573f0246 - rustc_query_system[85489b7677581133]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[c1c3c70d39a20423]::plumbing::QueryCtxt, false> 35: 0x7f7f573eff62 - rustc_query_impl[c1c3c70d39a20423]::query_impl::check_well_formed::get_query_non_incr::__rust_end_short_backtrace 36: 0x7f7f57e97bac - rustc_data_structures[1e82c702e6afba98]::sync::par_for_each_in::<&[rustc_hir[ef37331cc27c2adb]::hir::ImplItemId], ::par_impl_items::{closure#0}> 37: 0x7f7f57e9798a - rustc_hir_analysis[2c6ebfa0ec54105a]::check::wfcheck::check_mod_type_wf 38: 0x7f7f57865a4c - rustc_query_impl[c1c3c70d39a20423]::plumbing::__rust_begin_short_backtrace::> 39: 0x7f7f57865a2e - >::call_once 40: 0x7f7f573713ff - rustc_query_system[85489b7677581133]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[c1c3c70d39a20423]::plumbing::QueryCtxt, false> 41: 0x7f7f584ad142 - rustc_query_impl[c1c3c70d39a20423]::query_impl::check_mod_type_wf::get_query_non_incr::__rust_end_short_backtrace 42: 0x7f7f57fdb547 - rustc_data_structures[1e82c702e6afba98]::sync::par_for_each_in::<&[rustc_hir[ef37331cc27c2adb]::hir_id::OwnerId], ::par_for_each_module::{closure#0}> 43: 0x7f7f57fda8fe - rustc_hir_analysis[2c6ebfa0ec54105a]::check_crate 44: 0x7f7f57fd398a - rustc_interface[22a5bdce7fd6e981]::passes::analysis 45: 0x7f7f58027c3a - rustc_query_impl[c1c3c70d39a20423]::plumbing::__rust_begin_short_backtrace::> 46: 0x7f7f58027c29 - >::call_once 47: 0x7f7f581cbfa8 - rustc_query_system[85489b7677581133]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[c1c3c70d39a20423]::plumbing::QueryCtxt, false> 48: 0x7f7f581cbd37 - rustc_query_impl[c1c3c70d39a20423]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace 49: 0x7f7f57da39a5 - ::enter::> 50: 0x7f7f57da2fd2 - ::enter::, rustc_span[c85fb125fe1c027]::ErrorGuaranteed>> 51: 0x7f7f57d9c0a8 - std[cfe24ee53075a1e5]::sys_common::backtrace::__rust_begin_short_backtrace::, rustc_driver_impl[953ac255d00f3c7f]::run_compiler::{closure#1}>::{closure#0}, core[24a2ba61524efef7]::result::Result<(), rustc_span[c85fb125fe1c027]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[24a2ba61524efef7]::result::Result<(), rustc_span[c85fb125fe1c027]::ErrorGuaranteed>> 52: 0x7f7f57d9b82e - <::spawn_unchecked_, rustc_driver_impl[953ac255d00f3c7f]::run_compiler::{closure#1}>::{closure#0}, core[24a2ba61524efef7]::result::Result<(), rustc_span[c85fb125fe1c027]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[24a2ba61524efef7]::result::Result<(), rustc_span[c85fb125fe1c027]::ErrorGuaranteed>>::{closure#1} as core[24a2ba61524efef7]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} 53: 0x7f7f59d64445 - as core::ops::function::FnOnce>::call_once::h021e65daf5fb4ee0 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/alloc/src/boxed.rs:2007:9 54: 0x7f7f59d64445 - as core::ops::function::FnOnce>::call_once::h7dda744b120f2954 at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/alloc/src/boxed.rs:2007:9 55: 0x7f7f59d64445 - std::sys::unix::thread::Thread::new::thread_start::hcffeb1067f9b6dfb at /rustc/db7ff98a72f3e742b641f9cb16d0e8c285e87e9b/library/std/src/sys/unix/thread.rs:108:17 56: 0x7f7f552f96db - start_thread 57: 0x7f7f5502261f - clone 58: 0x0 - 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 `/home/coding/rustc-ice-2023-08-01T01:45:42.590021771Z-10152.txt` to your bug report query stack during panic: #0 [check_well_formed] checking that `A` is well-formed #1 [check_mod_type_wf] checking that types are well-formed in top-level module #2 [analysis] running analysis passes on this crate end of query stack error: aborting due to 2 previous errors; 1 warning emitted ```

[asquared31415]

This appears to be a different way to reproduce #114212

@rustbot label +F-generic-const-exprs +requires-incomplete-features

[iamanonymouscs]

This appears to be a different way to reproduce #114212

@rustbot label +F-generic-const-exprs +requires-incomplete-features

Thank you for bringing this🤗. Upon a thorough review, it appears that the query stacks for these two issues differ, suggesting that they are distinct Internal Compiler Errors (ICEs). However, we also notice that the compiler versions associated with these issues also differ. Thus, we cannot ascertain whether the variance in the query stack is because of the compiler versions.

[NightEule5]

These seem like related but different issues, or maybe the same issue but changed in newer compiler versions. Edit: same issue, the file was renamed in #113591

I encountered an ICE similar to this one, but with a pattern more similar to the older issue:

pub const SIZE: usize = 8192;

pub struct Segment<
    const N: usize = SIZE, // replacing with literal 8192 fixes it
    T = u8
> {
    _data: PhantomData<T>
}

The source of the panic is generic_args.rs:900:9, whereas in the linked issue it's subst.rs:896:9. I'm on the latest nightly, 1.74.0 (2023-08-26).

Here's my backtrace, if it's helpful:

Backtrace

``` thread 'rustc' panicked at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/compiler/rustc_errors/src/lib.rs:1649:9: Box stack backtrace: 0: 0x7fca5b562fac - std::backtrace_rs::backtrace::libunwind::trace::h7ead10aab469b9aa at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5 1: 0x7fca5b562fac - std::backtrace_rs::backtrace::trace_unsynchronized::hf548e9e8c1fe3e8d at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5 2: 0x7fca5b562fac - std::sys_common::backtrace::_print_fmt::h4f790d56eeca616b at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/sys_common/backtrace.rs:67:5 3: 0x7fca5b562fac - ::fmt::h30e5bb3d4404f378 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/sys_common/backtrace.rs:44:22 4: 0x7fca5b5c91dc - core::fmt::rt::Argument::fmt::h35f06f2256f98b43 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/core/src/fmt/rt.rs:138:9 5: 0x7fca5b5c91dc - core::fmt::write::h5005ce68dd6774c4 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/core/src/fmt/mod.rs:1094:21 6: 0x7fca5b555ace - std::io::Write::write_fmt::h2076d3e405c4c14e at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/io/mod.rs:1714:15 7: 0x7fca5b562d94 - std::sys_common::backtrace::_print::hedccafa15bd98864 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/sys_common/backtrace.rs:47:5 8: 0x7fca5b562d94 - std::sys_common::backtrace::print::h911d101d11c4e8b0 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/sys_common/backtrace.rs:34:9 9: 0x7fca5b565e8a - std::panicking::panic_hook_with_disk_dump::{{closure}}::he8cf7cbd1dd11756 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/panicking.rs:278:22 10: 0x7fca5b565b3a - std::panicking::panic_hook_with_disk_dump::h3baf172fecd393f6 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/panicking.rs:305:9 11: 0x7fca5e74a279 - >::call_once::{shim:vtable#0} 12: 0x7fca5b566731 - as core::ops::function::Fn>::call::h8e3b5b4f77120996 at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/alloc/src/boxed.rs:2021:9 13: 0x7fca5b566731 - std::panicking::rust_panic_with_hook::hcec56ff9d71a6f8a at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/panicking.rs:733:13 14: 0x7fca5ecfa761 - std[ebccec195fc5e844]::panicking::begin_panic::::{closure#0} 15: 0x7fca5ecf8556 - std[ebccec195fc5e844]::sys_common::backtrace::__rust_end_short_backtrace::::{closure#0}, !> 16: 0x7fca5eca72e6 - std[ebccec195fc5e844]::panicking::begin_panic:: 17: 0x7fca5ec64c64 - ::bug:: 18: 0x7fca5ec64af6 - ::bug:: 19: 0x7fca5ed1fe3c - rustc_middle[464349d56e47250b]::util::bug::opt_span_bug_fmt::::{closure#0} 20: 0x7fca5ed1e47a - rustc_middle[464349d56e47250b]::ty::context::tls::with_opt::::{closure#0}, !>::{closure#0} 21: 0x7fca5ed1e448 - rustc_middle[464349d56e47250b]::ty::context::tls::with_context_opt::::{closure#0}, !>::{closure#0}, !> 22: 0x7fca5d2e3f50 - rustc_middle[464349d56e47250b]::util::bug::bug_fmt 23: 0x7fca5ed10290 - ::type_param_out_of_range 24: 0x7fca5c861b23 - <&rustc_middle[464349d56e47250b]::ty::list::List as rustc_type_ir[e178ec1199739dae]::fold::TypeFoldable>::try_fold_with:: 25: 0x7fca5c83efc5 - ::instantiate_into 26: 0x7fca5caf1420 - ::nominal_obligations 27: 0x7fca5cad3085 - ::compute 28: 0x7fca5cac2422 - ::process_obligation 29: 0x7fca5cabdcf4 - >::process_obligations:: 30: 0x7fca5d0fa8e1 - ::select_all_or_error 31: 0x7fca5d04ff99 - rustc_hir_analysis[667fece327758e4f]::check::wfcheck::check_type_defn 32: 0x7fca5d02dffe - rustc_hir_analysis[667fece327758e4f]::check::wfcheck::check_well_formed 33: 0x7fca5c80409c - rustc_query_impl[58a3c40f53c1e9dd]::plumbing::__rust_begin_short_backtrace::> 34: 0x7fca5c80407c - >::call_once 35: 0x7fca5c92d6cc - rustc_query_system[771da89a8e6a97f0]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[58a3c40f53c1e9dd]::plumbing::QueryCtxt, true> 36: 0x7fca5c92d03b - rustc_query_impl[58a3c40f53c1e9dd]::query_impl::check_well_formed::get_query_incr::__rust_end_short_backtrace 37: 0x7fca5d9b9280 - rustc_data_structures[7283f0e76412c80]::sync::par_for_each_in::<&[rustc_hir[3a72116ea74f2480]::hir::ItemId], ::par_items::{closure#0}> 38: 0x7fca5d9b904f - rustc_hir_analysis[667fece327758e4f]::check::wfcheck::check_mod_type_wf 39: 0x7fca5d475c7c - rustc_query_impl[58a3c40f53c1e9dd]::plumbing::__rust_begin_short_backtrace::> 40: 0x7fca5d475c5e - >::call_once 41: 0x7fca5ddae0fb - rustc_query_system[771da89a8e6a97f0]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[58a3c40f53c1e9dd]::plumbing::QueryCtxt, true> 42: 0x7fca5e0ccee8 - rustc_query_impl[58a3c40f53c1e9dd]::query_impl::check_mod_type_wf::get_query_incr::__rust_end_short_backtrace 43: 0x7fca5d67069b - rustc_hir_analysis[667fece327758e4f]::check_crate 44: 0x7fca5d669c4a - rustc_interface[b81038288d48d278]::passes::analysis 45: 0x7fca5dc5ca4a - rustc_query_impl[58a3c40f53c1e9dd]::plumbing::__rust_begin_short_backtrace::> 46: 0x7fca5dc5ca39 - >::call_once 47: 0x7fca5df34ab8 - rustc_query_system[771da89a8e6a97f0]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[58a3c40f53c1e9dd]::plumbing::QueryCtxt, true> 48: 0x7fca5df34614 - rustc_query_impl[58a3c40f53c1e9dd]::query_impl::analysis::get_query_incr::__rust_end_short_backtrace 49: 0x7fca5da28da6 - ::enter::> 50: 0x7fca5da2822c - ::enter::, rustc_span[c92a35b362599b57]::ErrorGuaranteed>> 51: 0x7fca5da25548 - std[ebccec195fc5e844]::sys_common::backtrace::__rust_begin_short_backtrace::, rustc_driver_impl[98acc53e2d2f6ece]::run_compiler::{closure#1}>::{closure#0}, core[cb689c380e703cde]::result::Result<(), rustc_span[c92a35b362599b57]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[cb689c380e703cde]::result::Result<(), rustc_span[c92a35b362599b57]::ErrorGuaranteed>> 52: 0x7fca5dfc60f5 - <::spawn_unchecked_, rustc_driver_impl[98acc53e2d2f6ece]::run_compiler::{closure#1}>::{closure#0}, core[cb689c380e703cde]::result::Result<(), rustc_span[c92a35b362599b57]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[cb689c380e703cde]::result::Result<(), rustc_span[c92a35b362599b57]::ErrorGuaranteed>>::{closure#1} as core[cb689c380e703cde]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} 53: 0x7fca5b571195 - as core::ops::function::FnOnce>::call_once::hf6677bb1228f81ea at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/alloc/src/boxed.rs:2007:9 54: 0x7fca5b571195 - as core::ops::function::FnOnce>::call_once::h4f3130db7e13aaba at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/alloc/src/boxed.rs:2007:9 55: 0x7fca5b571195 - std::sys::unix::thread::Thread::new::thread_start::h17fc5e491c7b31dd at /rustc/69e97df5ce571a777acd654ec3697ae8d25962ea/library/std/src/sys/unix/thread.rs:108:17 56: 0x7fca5b28c9eb - 57: 0x7fca5b310ebc - 58: 0x0 - rustc version: 1.74.0-nightly (69e97df5c 2023-08-26) platform: x86_64-unknown-linux-gnu query stack during panic: #0 [check_well_formed] checking that `new::segment::Segment` is well-formed #1 [check_mod_type_wf] checking that types are well-formed in module `new::segment` #2 [analysis] running analysis passes on this crate end of query stack ```

[iamanonymouscs]

~These seem like related but different issues, or maybe the same issue but changed in newer compiler versions.~ Edit: same issue, the file was renamed in #113591

I encountered an ICE similar to this one, but with a pattern more similar to the older issue:

pub const SIZE: usize = 8192;

pub struct Segment<
    const N: usize = SIZE, // replacing with literal 8192 fixes it
    T = u8
> {
    _data: PhantomData<T>
}

The source of the panic is generic_args.rs:900:9, whereas in the linked issue it's subst.rs:896:9. I'm on the latest nightly, 1.74.0 (2023-08-26).

Here's my backtrace, if it's helpful:

Backtrace

Thank you very much for your reply. I think I have gained a better understanding of Rustc😃🚀

[gurry]

@rustbot claim

[gurry]

Duplicate of #106994

Perhaps we can close this one in favour of that.

[gurry]

@rustbot release-assignment