[ICE]: invalid immediate for given destination place: scalar value has wrong size #153236
Description
auto-reduced (treereduce-rust):
#![feature(field_projections)]
use std::field::{field_of, Field};
use std::mem::offset_of;
#[repr(C)]
pub struct Struct {
a: i32,
b: i64,
}
fn main() {
assert_eq!(<field_of!(Struct, b)>::OFFSET, offset_of!((), ()));
}original code
original:
//@ revisions: old next
//@ [next] compile-flags: -Znext-solver
//@ run-pass
#![expect(incomplete_features)]
#![feature(field_projections)]
use std::field::{Field, field_of};
use std::mem::offset_of;
use std::ptr;
#[repr(C)]
pub struct Struct {
a: i32,
b: i64,
}
// FIXME(FRTs): need to mark these fields as used by the `field_of!` macro.
#[expect(dead_code)]
pub union Union {
a: i32,
b: i64,
}
#[repr(C, i8)]
pub enum Enum {
A { a: i32, b: i64 },
B { x: i64, y: i32 },
}
fn project_ref<'a, T, F: Field<Base = T>>(r: &'a T) -> &'a F::Type {
unsafe { &*ptr::from_ref(r).byte_add(F::OFFSET).cast() }
}
fn main() {
assert_eq!(<field_of!(Struct, a)>::OFFSET, offset_of!(Struct, a));
assert_eq!(<field_of!(Struct, b)>::OFFSET, offset_of!((), ()));
let _: field_of!(Union, a);
let _: field_of!(Union, b);
let _: field_of!(Enum, A.a);
let _: field_of!(Enum, A.b);
let _: field_of!(Enum, B.x);
let _: field_of!(Enum, B.y);
let s = Struct { a: 42, b: 24 };
let r = &s;
let a = project_ref::<Struct, field_of!(Struct, a)>(r);
let b = project_ref::<Struct, field_of!(Struct, b)>(r);
assert_eq!(*a, 42);
assert_eq!(*b, 24);
}Version information
rustc 1.96.0-nightly (ba1567989 2026-02-28)
binary: rustc
commit-hash: ba1567989ee7774a1fb53aa680a8e4e8daa0f519
commit-date: 2026-02-28
host: x86_64-unknown-linux-gnu
release: 1.96.0-nightly
LLVM version: 22.1.0
Possibly related line of code:
rust/compiler/rustc_const_eval/src/interpret/operand.rs
Lines 116 to 128 in ba15679
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc
Program output
error: offset_of expects dot-separated field and variant names
--> b.rs:13:63
|
13 | assert_eq!(<field_of!(Struct, b)>::OFFSET, offset_of!((), ()));
| ^^
warning: the feature `field_projections` is incomplete and may not be safe to use and/or cause compiler crashes
--> b.rs:1:12
|
1 | #![feature(field_projections)]
| ^^^^^^^^^^^^^^^^^
|
= note: see issue #145383 <https://github.com/rust-lang/rust/issues/145383> for more information
= note: `#[warn(incomplete_features)]` on by default
thread 'rustc' (2095317) panicked at /rustc-dev/ba1567989ee7774a1fb53aa680a8e4e8daa0f519/compiler/rustc_const_eval/src/interpret/operand.rs:122:17:
assertion `left == right` failed: invalid immediate for given destination place: scalar value has wrong size
left: Size(4 bytes)
right: Size(8 bytes)
stack backtrace:
0: 0x7f13cf9aa67b - <<std[fec5da352f41df64]::sys::backtrace::BacktraceLock>::print::DisplayBacktrace as core[655421083fc59668]::fmt::Display>::fmt
1: 0x7f13d0020288 - core[655421083fc59668]::fmt::write
2: 0x7f13cf9c1686 - <std[fec5da352f41df64]::sys::stdio::unix::Stderr as std[fec5da352f41df64]::io::Write>::write_fmt
3: 0x7f13cf980758 - std[fec5da352f41df64]::panicking::default_hook::{closure#0}
4: 0x7f13cf99dae3 - std[fec5da352f41df64]::panicking::default_hook
5: 0x7f13ce975070 - std[fec5da352f41df64]::panicking::update_hook::<alloc[c081135bcfa9263a]::boxed::Box<rustc_driver_impl[a0a5e0825e3525c3]::install_ice_hook::{closure#1}>>::{closure#0}
6: 0x7f13cf99ddc2 - std[fec5da352f41df64]::panicking::panic_with_hook
7: 0x7f13cf980818 - std[fec5da352f41df64]::panicking::panic_handler::{closure#0}
8: 0x7f13cf977549 - std[fec5da352f41df64]::sys::backtrace::__rust_end_short_backtrace::<std[fec5da352f41df64]::panicking::panic_handler::{closure#0}, !>
9: 0x7f13cf98227d - __rustc[70948dbd69585b06]::rust_begin_unwind
10: 0x7f13cc51fefc - core[655421083fc59668]::panicking::panic_fmt
11: 0x7f13ce2c0243 - core[655421083fc59668]::panicking::assert_failed_inner
12: 0x7f13cef743ce - core[655421083fc59668]::panicking::assert_failed::<rustc_abi[efb49786af623574]::Size, rustc_abi[efb49786af623574]::Size>
13: 0x7f13d046cbd7 - <rustc_const_eval[60546f5659a7e5b8]::interpret::eval_context::InterpCx<rustc_const_eval[60546f5659a7e5b8]::const_eval::machine::CompileTimeMachine>>::copy_op_no_validate::<rustc_const_eval[60546f5659a7e5b8]::interpret::operand::OpTy, rustc_const_eval[60546f5659a7e5b8]::interpret::place::PlaceTy>
14: 0x7f13d10ac948 - rustc_const_eval[60546f5659a7e5b8]::const_eval::eval_queries::eval_to_allocation_raw_provider
15: 0x7f13d10aae1c - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_allocation_raw::invoke_provider_fn::__rust_begin_short_backtrace
16: 0x7f13d0e6df83 - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_middle[487438de6df3e06a]::query::caches::DefaultCache<rustc_middle[487438de6df3e06a]::ty::PseudoCanonicalInput<rustc_middle[487438de6df3e06a]::mir::interpret::GlobalId>, rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 24usize]>>, false>
17: 0x7f13d0e6d8eb - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_allocation_raw::execute_query_non_incr::__rust_end_short_backtrace
18: 0x7f13d0e6f521 - rustc_const_eval[60546f5659a7e5b8]::const_eval::eval_queries::eval_to_const_value_raw_provider
19: 0x7f13d0e6f0a8 - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_const_value_raw::invoke_provider_fn::__rust_begin_short_backtrace
20: 0x7f13d0e6de87 - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_middle[487438de6df3e06a]::query::caches::DefaultCache<rustc_middle[487438de6df3e06a]::ty::PseudoCanonicalInput<rustc_middle[487438de6df3e06a]::mir::interpret::GlobalId>, rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 24usize]>>, false>
21: 0x7f13d0e6d9eb - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_const_value_raw::execute_query_non_incr::__rust_end_short_backtrace
22: 0x7f13d0c5db20 - <rustc_middle[487438de6df3e06a]::ty::context::TyCtxt>::const_eval_resolve
23: 0x7f13d0761d8e - <rustc_mir_transform[375a1252ba647aa9]::known_panics_lint::ConstPropagator as rustc_middle[487438de6df3e06a]::mir::visit::Visitor>::visit_assign
24: 0x7f13d075dc36 - <rustc_mir_transform[375a1252ba647aa9]::known_panics_lint::ConstPropagator as rustc_middle[487438de6df3e06a]::mir::visit::Visitor>::visit_body
25: 0x7f13d075afe8 - <rustc_mir_transform[375a1252ba647aa9]::known_panics_lint::KnownPanicsLint as rustc_mir_transform[375a1252ba647aa9]::pass_manager::MirLint>::run_lint
26: 0x7f13d000ca6a - rustc_mir_transform[375a1252ba647aa9]::run_analysis_to_runtime_passes
27: 0x7f13d0de3034 - rustc_mir_transform[375a1252ba647aa9]::promoted_mir
28: 0x7f13d0de2cb3 - rustc_query_impl[83437f7fc475934b]::query_impl::promoted_mir::invoke_provider_fn::__rust_begin_short_backtrace
29: 0x7f13d005a4e8 - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_middle[487438de6df3e06a]::query::caches::DefIdCache<rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 8usize]>>, false>
30: 0x7f13d0059764 - rustc_query_impl[83437f7fc475934b]::query_impl::promoted_mir::execute_query_non_incr::__rust_end_short_backtrace
31: 0x7f13d10aa9e4 - <rustc_const_eval[60546f5659a7e5b8]::interpret::eval_context::InterpCx<rustc_const_eval[60546f5659a7e5b8]::const_eval::machine::CompileTimeMachine>>::load_mir
32: 0x7f13d10ab59a - rustc_const_eval[60546f5659a7e5b8]::const_eval::eval_queries::eval_to_allocation_raw_provider
33: 0x7f13d10aae1c - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_allocation_raw::invoke_provider_fn::__rust_begin_short_backtrace
34: 0x7f13d0e6df83 - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_middle[487438de6df3e06a]::query::caches::DefaultCache<rustc_middle[487438de6df3e06a]::ty::PseudoCanonicalInput<rustc_middle[487438de6df3e06a]::mir::interpret::GlobalId>, rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 24usize]>>, false>
35: 0x7f13d0e6d8eb - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_allocation_raw::execute_query_non_incr::__rust_end_short_backtrace
36: 0x7f13d0e6f521 - rustc_const_eval[60546f5659a7e5b8]::const_eval::eval_queries::eval_to_const_value_raw_provider
37: 0x7f13d0e6f0a8 - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_const_value_raw::invoke_provider_fn::__rust_begin_short_backtrace
38: 0x7f13d0e6de87 - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_middle[487438de6df3e06a]::query::caches::DefaultCache<rustc_middle[487438de6df3e06a]::ty::PseudoCanonicalInput<rustc_middle[487438de6df3e06a]::mir::interpret::GlobalId>, rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 24usize]>>, false>
39: 0x7f13d0e6d9eb - rustc_query_impl[83437f7fc475934b]::query_impl::eval_to_const_value_raw::execute_query_non_incr::__rust_end_short_backtrace
40: 0x7f13d0c5db20 - <rustc_middle[487438de6df3e06a]::ty::context::TyCtxt>::const_eval_resolve
41: 0x7f13d0761d8e - <rustc_mir_transform[375a1252ba647aa9]::known_panics_lint::ConstPropagator as rustc_middle[487438de6df3e06a]::mir::visit::Visitor>::visit_assign
42: 0x7f13d075dc36 - <rustc_mir_transform[375a1252ba647aa9]::known_panics_lint::ConstPropagator as rustc_middle[487438de6df3e06a]::mir::visit::Visitor>::visit_body
43: 0x7f13d075afe8 - <rustc_mir_transform[375a1252ba647aa9]::known_panics_lint::KnownPanicsLint as rustc_mir_transform[375a1252ba647aa9]::pass_manager::MirLint>::run_lint
44: 0x7f13d000ca6a - rustc_mir_transform[375a1252ba647aa9]::run_analysis_to_runtime_passes
45: 0x7f13d0de1784 - rustc_mir_transform[375a1252ba647aa9]::mir_drops_elaborated_and_const_checked
46: 0x7f13d0de11e1 - rustc_query_impl[83437f7fc475934b]::query_impl::mir_drops_elaborated_and_const_checked::invoke_provider_fn::__rust_begin_short_backtrace
47: 0x7f13d016790a - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_data_structures[e05ccdf9cc6e0e20]::vec_cache::VecCache<rustc_span[8c85abb5df2f449]::def_id::LocalDefId, rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 8usize]>, rustc_middle[487438de6df3e06a]::dep_graph::graph::DepNodeIndex>, false>
48: 0x7f13d0167043 - rustc_query_impl[83437f7fc475934b]::query_impl::mir_drops_elaborated_and_const_checked::execute_query_non_incr::__rust_end_short_backtrace
49: 0x7f13d01653c8 - <rustc_middle[487438de6df3e06a]::ty::context::TyCtxt>::par_hir_body_owners::<rustc_interface[b660c6c936fc555e]::passes::run_required_analyses::{closure#1}::{closure#0}>::{closure#0}
50: 0x7f13d01647af - rustc_interface[b660c6c936fc555e]::passes::analysis
51: 0x7f13d120925a - rustc_query_impl[83437f7fc475934b]::execution::try_execute_query::<rustc_middle[487438de6df3e06a]::query::caches::SingleCache<rustc_middle[487438de6df3e06a]::query::erase::ErasedData<[u8; 0usize]>>, false>
52: 0x7f13d1209029 - rustc_query_impl[83437f7fc475934b]::query_impl::analysis::execute_query_non_incr::__rust_end_short_backtrace
53: 0x7f13d1229c2d - rustc_interface[b660c6c936fc555e]::interface::run_compiler::<(), rustc_driver_impl[a0a5e0825e3525c3]::run_compiler::{closure#0}>::{closure#1}
54: 0x7f13d11f653e - std[fec5da352f41df64]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[b660c6c936fc555e]::util::run_in_thread_with_globals<rustc_interface[b660c6c936fc555e]::util::run_in_thread_pool_with_globals<rustc_interface[b660c6c936fc555e]::interface::run_compiler<(), rustc_driver_impl[a0a5e0825e3525c3]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
55: 0x7f13d11f6ba0 - <std[fec5da352f41df64]::thread::lifecycle::spawn_unchecked<rustc_interface[b660c6c936fc555e]::util::run_in_thread_with_globals<rustc_interface[b660c6c936fc555e]::util::run_in_thread_pool_with_globals<rustc_interface[b660c6c936fc555e]::interface::run_compiler<(), rustc_driver_impl[a0a5e0825e3525c3]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[655421083fc59668]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
56: 0x7f13d11f7a2c - <std[fec5da352f41df64]::sys::thread::unix::Thread>::new::thread_start
57: 0x7f13caca598b - <unknown>
58: 0x7f13cad29a0c - <unknown>
59: 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: please make sure that you have updated to the latest nightly
note: please attach the file at `/tmp/im/rustc-ice-2026-02-28T20_48_10-2095315.txt` to your bug report
note: rustc 1.96.0-nightly (ba1567989 2026-02-28) running on x86_64-unknown-linux-gnu
query stack during panic:
#0 [eval_to_allocation_raw] const-evaluating + checking `main::{constant#0}`
#1 [eval_to_const_value_raw] simplifying constant for the type system `main::{constant#0}`
|
= note: this failure-note originates in the macro `offset_of` (in Nightly builds, run with -Z macro-backtrace for more info)
#2 [promoted_mir] optimizing promoted MIR for `main`
#3 [eval_to_allocation_raw] const-evaluating + checking `main::promoted[1]`
#4 [eval_to_const_value_raw] simplifying constant for the type system `main::promoted[1]`
#5 [mir_drops_elaborated_and_const_checked] elaborating drops for `main`
#6 [analysis] running analysis passes on crate `b`
end of query stack
error: aborting due to 1 previous error; 1 warning emitted
@rustbot label +F-field_projections
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