ICE: symbol: assertion left != right failed

[matthiaskrgr]

auto-reduced (treereduce-rust):

unsafe fn setup_boostrap_code<A>(args: &A) {
    extern "" {}
}

original:

unsafe fn setup_boostrap_code<A>(args: &A) {
    extern "" {
        static xxx: *const u64
    }
    // Arguments
    let arg1_pointer_new: *const A = core::mem::transmute::transmute(&xxx);
}

fn main() {}

Version information

rustc 1.89.0-nightly (dcecb9917 2025-05-09)
binary: rustc
commit-hash: dcecb99176edf2eec51613730937d21cdd5c8f6e
commit-date: 2025-05-09
host: x86_64-unknown-linux-gnu
release: 1.89.0-nightly
LLVM version: 20.1.4

Possibly related line of code:

rust/compiler/rustc_span/src/symbol.rs

Lines 2349 to 2361 in dcecb99

	}
	impl Ident {
	#[inline]
	/// Constructs a new identifier from a symbol and a span.
	pub fn new(name: Symbol, span: Span) -> Ident {
	assert_ne!(name, kw::Empty);
	Ident { name, span }
	}
	/// Constructs a new identifier with a dummy span.
	#[inline]
	pub fn with_dummy_span(name: Symbol) -> Ident {

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc

Program output

thread 'rustc' panicked at compiler/rustc_span/src/symbol.rs:2355:9:
assertion `left != right` failed
  left: ""
 right: ""
stack backtrace:
   0:     0x7f9791b5d8b3 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::hc5cbdf8d27100af3
   1:     0x7f9792205c07 - core::fmt::write::h863d3bbf4c00e6b0
   2:     0x7f9793300ad1 - std::io::Write::write_fmt::h912feb91ff6a0610
   3:     0x7f9791b5d712 - std::sys::backtrace::BacktraceLock::print::hd1d99a58bb496c4c
   4:     0x7f9791b6130a - std::panicking::default_hook::{{closure}}::h0ae138d3e765f04d
   5:     0x7f9791b60e8f - std::panicking::default_hook::h197fce4b22dcc9b4
   6:     0x7f9790b90093 - std[7b29bb91ebdb57c9]::panicking::update_hook::<alloc[a0860bb7f030fe8a]::boxed::Box<rustc_driver_impl[b019fded3476e915]::install_ice_hook::{closure#1}>>::{closure#0}
   7:     0x7f9791b61b83 - std::panicking::rust_panic_with_hook::hc11797ac2ff063c3
   8:     0x7f9791b6187a - std::panicking::begin_panic_handler::{{closure}}::h629cd41fb69152ef
   9:     0x7f9791b5dd89 - std::sys::backtrace::__rust_end_short_backtrace::hc4d9aeb15faa7765
  10:     0x7f9791b6153d - __rustc[3da6fc54cdd59cb4]::rust_begin_unwind
  11:     0x7f978e486d20 - core::panicking::panic_fmt::h0e2a987d4942fb3a
  12:     0x7f979050961a - core::panicking::assert_failed_inner::h17f3e3254adaa208
  13:     0x7f97904456f8 - core[d6ce3f6d63d0f33a]::panicking::assert_failed::<rustc_span[38259b213a6a0c93]::symbol::Symbol, rustc_span[38259b213a6a0c93]::symbol::Symbol>
  14:     0x7f9792b3311a - <rustc_span[38259b213a6a0c93]::symbol::Symbol>::to_ident_string
  15:     0x7f9790718157 - <rustc_errors[1cd13ce2e937c1a0]::diagnostic::Diag>::arg::<&str, rustc_span[38259b213a6a0c93]::symbol::Symbol>
  16:     0x7f979273d766 - <rustc_ast_lowering[19179cac93daefe0]::LoweringContext>::lower_abi
  17:     0x7f97933f412b - <rustc_ast_lowering[19179cac93daefe0]::LoweringContext>::lower_item_kind
  18:     0x7f9792754145 - <rustc_ast_lowering[19179cac93daefe0]::item::ItemLowerer>::lower_node
  19:     0x7f9792752ca5 - rustc_ast_lowering[19179cac93daefe0]::lower_to_hir
  20:     0x7f9793098eaa - rustc_query_impl[e2aea24a209ecfad]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[e2aea24a209ecfad]::query_impl::hir_crate::dynamic_query::{closure#2}::{closure#0}, rustc_middle[9f3ff6a4a17a20f0]::query::erase::Erased<[u8; 8usize]>>
  21:     0x7f979318ae01 - rustc_query_system[bd0c30a71f71891a]::query::plumbing::try_execute_query::<rustc_query_impl[e2aea24a209ecfad]::DynamicConfig<rustc_query_system[bd0c30a71f71891a]::query::caches::SingleCache<rustc_middle[9f3ff6a4a17a20f0]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[e2aea24a209ecfad]::plumbing::QueryCtxt, false>
  22:     0x7f979318a408 - rustc_query_impl[e2aea24a209ecfad]::query_impl::hir_crate::get_query_non_incr::__rust_end_short_backtrace
  23:     0x7f979250699c - rustc_interface[e50761f90850a00f]::passes::run_required_analyses
  24:     0x7f97931f8a9e - rustc_interface[e50761f90850a00f]::passes::analysis
  25:     0x7f97931f8a75 - rustc_query_impl[e2aea24a209ecfad]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[e2aea24a209ecfad]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[9f3ff6a4a17a20f0]::query::erase::Erased<[u8; 0usize]>>
  26:     0x7f97931888fa - rustc_query_system[bd0c30a71f71891a]::query::plumbing::try_execute_query::<rustc_query_impl[e2aea24a209ecfad]::DynamicConfig<rustc_query_system[bd0c30a71f71891a]::query::caches::SingleCache<rustc_middle[9f3ff6a4a17a20f0]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[e2aea24a209ecfad]::plumbing::QueryCtxt, false>
  27:     0x7f97931885cf - rustc_query_impl[e2aea24a209ecfad]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  28:     0x7f9793471f87 - rustc_interface[e50761f90850a00f]::passes::create_and_enter_global_ctxt::<core[d6ce3f6d63d0f33a]::option::Option<rustc_interface[e50761f90850a00f]::queries::Linker>, rustc_driver_impl[b019fded3476e915]::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}
  29:     0x7f979333c5e6 - rustc_interface[e50761f90850a00f]::interface::run_compiler::<(), rustc_driver_impl[b019fded3476e915]::run_compiler::{closure#0}>::{closure#1}
  30:     0x7f97932f777e - std[7b29bb91ebdb57c9]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[e50761f90850a00f]::util::run_in_thread_with_globals<rustc_interface[e50761f90850a00f]::util::run_in_thread_pool_with_globals<rustc_interface[e50761f90850a00f]::interface::run_compiler<(), rustc_driver_impl[b019fded3476e915]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
  31:     0x7f97932f7bf4 - <<std[7b29bb91ebdb57c9]::thread::Builder>::spawn_unchecked_<rustc_interface[e50761f90850a00f]::util::run_in_thread_with_globals<rustc_interface[e50761f90850a00f]::util::run_in_thread_pool_with_globals<rustc_interface[e50761f90850a00f]::interface::run_compiler<(), rustc_driver_impl[b019fded3476e915]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[d6ce3f6d63d0f33a]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  32:     0x7f97932f8feb - std::sys::pal::unix::thread::Thread::new::thread_start::h0908bf6e72bc0de5
  33:     0x7f978d0a370a - <unknown>
  34:     0x7f978d127aac - <unknown>
  35:                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: rustc 1.89.0-nightly (dcecb9917 2025-05-09) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [hir_crate] getting the crate HIR
#1 [analysis] running analysis passes on this crate
end of query stack

[matthiaskrgr]

mvce

fn a() {
    extern "" {}
}

#140252 cc @nnethercote

[matthiaskrgr]

adding label because of #140880 which will land soon-ish