[ICE]: Instance::mono: DefId(0:3 ~ ice_min_repro[2fa7]::foo) has type parameters when building with Miri
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@HerrCai0907 is already working on this.
Since Mar 29, 2026.
A-miri
A-name-mangling
C-bug
I-ICE
T-compiler
- Dominant language
- Rust
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Description
When building the code below with cargo miri test, the compiler produces the following error
Code
#[unsafe(no_mangle)]
fn foo<T: std::fmt::Debug>(value: T) {
println!("{value:?}");
}
Meta
rustc --version --verbose:
rustc 1.96.0-nightly (fd0c901b0 2026-03-18)
binary: rustc
commit-hash: fd0c901b00ee1e08a250039cdb90258603497e20
commit-date: 2026-03-18
host: x86_64-pc-windows-msvc
release: 1.96.0-nightly
LLVM version: 22.1.0
Error output
error: internal compiler error: /rustc-dev/fd0c901b00ee1e08a250039cdb90258603497e20/compiler\rustc_middle\src\ty\instance.rs:458:17: Instance::mono: DefId(0:3 ~ ice_min_repro[2fa7]::foo) has type parameters
Backtrace
thread 'rustc' panicked at /rustc-dev/fd0c901b00ee1e08a250039cdb90258603497e20/compiler\rustc_middle\src\ty\instance.rs:458:17:
Box<dyn Any>
stack backtrace:
0: 0x7ffe8a0cacae - std::backtrace_rs::backtrace::win64::trace
at /rustc/fd0c901b00ee1e08a250039cdb90258603497e20/library\std\src\..\..\backtrace\src\backtrace\win64.rs:85
1: 0x7ffe8a0cacae - std::backtrace_rs::backtrace::trace_unsynchronized
at /rustc/fd0c901b00ee1e08a250039cdb90258603497e20/library\std\src\..\..\backtrace\src\backtrace\mod.rs:66
2: 0x7ffe8a0cacae - std::backtrace::Backtrace::create
at /rustc/fd0c901b00ee1e08a250039cdb90258603497e20/library\std\src\backtrace.rs:331
3: 0x7ffe8a0cabea - std::backtrace::Backtrace::force_capture
at /rustc/fd0c901b00ee1e08a250039cdb90258603497e20/library\std\src\backtrace.rs:312
4: 0x7ffe8b8b5409 - core[e8082310acd5b989]::slice::sort::unstable::heapsort::heapsort::<((rustc_lint_defs[ecb82c43dc0b6007]::Level, &str), usize), <((rustc_lint_defs[ecb82c43dc0b6007]::Level, &str), usize) as core[e8082310acd5b989]::cmp::PartialOrd>::lt>
5: 0x7ffe8a0dea24 - std::panicking::panic_with_hook
at /rustc/fd0c901b00ee1e08a250039cdb90258603497e20/library\std\src\panicking.rs:833
6: 0x7ffe8e078143 - core[e8082310acd5b989]::slice::sort::stable::quicksort::quicksort::<rustc_errors[444c0105aea6caf9]::annotate_snippet_emitter_writer::Annotation, <[rustc_errors[444c0105aea6caf9]::annotate_snippet_emitter_writer::Annotation]>::sort_by_key<usize, rustc_errors[444c0105aea6caf9]::annotate_snippet_emitter_writer::collect_annotations::{closure#2}>::{closure#0}>
7: 0x7ffe8e070549 - std[68781d2d012a60d0]::sys::backtrace::__rust_end_short_backtrace::<std[68781d2d012a60d0]::panicking::begin_panic<rustc_errors[444c0105aea6caf9]::ExplicitBug>::{closure#0}, !>
8: 0x7ffe8e06d9c8 - std[68781d2d012a60d0]::panicking::begin_panic::<rustc_errors[444c0105aea6caf9]::ExplicitBug>
9: 0x7ffe8e0856d5 - <rustc_errors[444c0105aea6caf9]::diagnostic::BugAbort as rustc_errors[444c0105aea6caf9]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
10: 0x7ffe8df599e7 - <rustc_data_structures[4c5f9f02e597ed01]::profiling::SelfProfilerRef>::exec::cold_call::<<rustc_data_structures[4c5f9f02e597ed01]::profiling::SelfProfilerRef>::incr_result_hashing::{closure#0}>
11: 0x7ffe8df59a75 - <rustc_data_structures[4c5f9f02e597ed01]::profiling::SelfProfilerRef>::exec::cold_call::<<rustc_data_structures[4c5f9f02e597ed01]::profiling::SelfProfilerRef>::incr_result_hashing::{closure#0}>
12: 0x7ffe8df46276 - rustc_middle[76db7d767fe7a6dd]::util::bug::span_bug_fmt::<rustc_span[a92fa7ebee9fddee]::span_encoding::Span>
13: 0x7ffe8df96786 - rustc_middle[76db7d767fe7a6dd]::util::bug::bug_fmt
14: 0x7ffe8b67a882 - <hashbrown[ec495549107772b4]::raw::RawTable<usize>>::reserve_rehash::<indexmap[d30d657db8fcb2f1]::inner::get_hash<rustc_middle[76db7d767fe7a6dd]::middle::region::Scope, rustc_middle[76db7d767fe7a6dd]::middle::region::Scope>::{closure#0}>
15: 0x7ffe8b6db518 - <rustc_middle[76db7d767fe7a6dd]::ty::instance::Instance>::mono
16: 0x7ff6b00174b6 - <unknown>
17: 0x7ff6b0131f54 - <unknown>
18: 0x7ff6b00b80e6 - <unknown>
19: 0x7ff6b0001860 - <unknown>
20: 0x7ff6b0195d7c - <unknown>
21: 0x7ff6b0134e6d - <unknown>
22: 0x7ff6b0130c0c - <unknown>
23: 0x7ff6b00892a2 - <unknown>
24: 0x7ff6b0012329 - <unknown>
25: 0x7ff6b00b2e8e - <unknown>
26: 0x7ff6aff9202e - <unknown>
27: 0x7ffe873dbaa5 - std[68781d2d012a60d0]::sys::backtrace::__rust_begin_short_backtrace::<std[68781d2d012a60d0]::thread::lifecycle::spawn_unchecked<ctrlc[fec3e3798385aa32]::set_handler_inner<rustc_driver_impl[2801a1d0af7dc0fc]::install_ctrlc_handler::{closure#0}>::{closure#0}, ()>::{closure#1}::{closure#0}::{closure#0}, ()>
28: 0x7ffe873d59f1 - RINvNtNtCs8Y5oIjIOpQ2_3std3sys9backtrace28___rust_begin_short_backtraceNCNCINvNtCs373VuARm7TT_15rustc_interface4util26run_in_thread_with_globalsNCINvB1e_31run_in_thread_pool_with_globalsNCINvNtB1g_9interface12run_compileruNCNvCs3qX5jVGyLmW_17rustc_driver_i
29: 0x7ffe873e09da - std[68781d2d012a60d0]::sys::backtrace::__rust_begin_short_backtrace::<std[68781d2d012a60d0]::thread::lifecycle::spawn_unchecked<ctrlc[fec3e3798385aa32]::set_handler_inner<rustc_driver_impl[2801a1d0af7dc0fc]::install_ctrlc_handler::{closure#0}>::{closure#0}, ()>::{closure#1}::{closure#0}::{closure#0}, ()>
30: 0x7ffe8a0e866c - std::sys::thread::windows::impl$0::new::thread_start
at /rustc/fd0c901b00ee1e08a250039cdb90258603497e20/library\std\src\sys\thread\windows.rs:58
31: 0x7fff2c05e8d7 - BaseThreadInitThunk
32: 0x7fff2d6ec48c - RtlUserThreadStart
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