rustdoc: assertion failed: !name.is_empty()

[kpreid]

Code

Run cargo +nightly doc on:

/// [`String::`]
pub struct Foo;

Original non-minimal repro

cargo add wgpu-types@25.0.0
cargo +nightly rustdoc -p wgpu-types

Meta

rustc --version --verbose:

rustc 1.86.0 (05f9846f8 2025-03-31)
binary: rustc
commit-hash: 05f9846f893b09a1be1fc8560e33fc3c815cfecb
commit-date: 2025-03-31
host: aarch64-apple-darwin
release: 1.86.0
LLVM version: 19.1.7

Error output

thread 'rustc' panicked at compiler/rustc_middle/src/ty/assoc.rs:253:9:
assertion failed: !name.is_empty()
stack backtrace:
   0:        0x1114c4db0 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::ha26fa7c0f8baf7a4
   1:        0x10eb4b510 - core::fmt::write::h8eff90b819ed25ac
   2:        0x1114b9b90 - std::io::Write::write_fmt::hc3767759e8313866
   3:        0x1114c4c70 - std::sys::backtrace::BacktraceLock::print::h5ab5bdfc8c7040c6
   4:        0x1114c94c0 - std::panicking::default_hook::{{closure}}::h3ff3b576237b0679
   5:        0x1114c918c - std::panicking::default_hook::h2517e562906dc496
   6:        0x10f68d2c8 - std[b96ff11cec95bebb]::panicking::update_hook::<alloc[10845a2db80e37c3]::boxed::Box<rustc_driver_impl[1cdaafc69be13d9e]::install_ice_hook::{closure#1}>>::{closure#0}
   7:        0x1114c9eac - std::panicking::rust_panic_with_hook::hdf5ea4a7520fe9b8
   8:        0x1114c9a78 - std::panicking::begin_panic_handler::{{closure}}::h7e667cf4bf22d5a9
   9:        0x1114c5248 - std::sys::backtrace::__rust_end_short_backtrace::h6ac6505b1a15fed1
  10:        0x1114c9768 - __rustc[e5679b3fd213e125]::rust_begin_unwind
  11:        0x114103028 - core::panicking::panic_fmt::h0d9b963f0cbbd487
  12:        0x114103098 - core::panicking::panic::h9fec57903899a361
  13:        0x1102be8fc - <rustc_middle[b00788c921925d5f]::ty::assoc::AssocItems>::filter_by_name_unhygienic
  14:        0x103064668 - rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::filter_assoc_items_by_name_and_namespace
  15:        0x102f099e0 - <core[77d52d671b80b66]::iter::adapters::map::Map<core[77d52d671b80b66]::iter::adapters::flatten::FlatMap<core[77d52d671b80b66]::slice::iter::Iter<rustc_span[5eba1f9f6065b66a]::def_id::DefId>, core[77d52d671b80b66]::iter::adapters::filter::Filter<core[77d52d671b80b66]::iter::adapters::map::Map<core[77d52d671b80b66]::iter::adapters::map_while::MapWhile<core[77d52d671b80b66]::slice::iter::Iter<u32>, <rustc_data_structures[afa636c047cbec44]::sorted_map::index_map::SortedIndexMultiMap<u32, core[77d52d671b80b66]::option::Option<rustc_span[5eba1f9f6065b66a]::symbol::Symbol>, rustc_middle[b00788c921925d5f]::ty::assoc::AssocItem>>::get_by_key_enumerated::{closure#1}>, <rustc_data_structures[afa636c047cbec44]::sorted_map::index_map::SortedIndexMultiMap<u32, core[77d52d671b80b66]::option::Option<rustc_span[5eba1f9f6065b66a]::symbol::Symbol>, rustc_middle[b00788c921925d5f]::ty::assoc::AssocItem>>::get_by_key::{closure#0}>, rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::filter_assoc_items_by_name_and_namespace::{closure#0}>, <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector>::resolve_associated_item::{closure#2}>, <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector>::resolve_associated_item::{closure#3}> as core[77d52d671b80b66]::iter::traits::iterator::Iterator>::next
  16:        0x1030671c4 - <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector>::resolve_associated_item
  17:        0x103065cc0 - <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector>::resolve
  18:        0x10306abbc - <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector>::resolve_link
  19:        0x1030b4284 - <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector>::resolve_links
  20:        0x103091448 - <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector as rustdoc[535d2b71f692d26c]::visit::DocVisitor>::visit_inner_recur
  21:        0x103091480 - <rustdoc[535d2b71f692d26c]::passes::collect_intra_doc_links::LinkCollector as rustdoc[535d2b71f692d26c]::visit::DocVisitor>::visit_inner_recur
  22:        0x102fb65e8 - rustdoc[535d2b71f692d26c]::core::run_global_ctxt
  23:        0x103099f88 - rustdoc[535d2b71f692d26c]::main_args::{closure#2}::{closure#0}
  24:        0x102e83cb8 - rustc_interface[657d728ad44a5017]::interface::run_compiler::<(), rustdoc[535d2b71f692d26c]::main_args::{closure#2}>::{closure#1}
  25:        0x102e19dfc - std[b96ff11cec95bebb]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[657d728ad44a5017]::util::run_in_thread_with_globals<rustc_interface[657d728ad44a5017]::util::run_in_thread_pool_with_globals<rustc_interface[657d728ad44a5017]::interface::run_compiler<(), rustdoc[535d2b71f692d26c]::main_args::{closure#2}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
  26:        0x102e95e74 - <<std[b96ff11cec95bebb]::thread::Builder>::spawn_unchecked_<rustc_interface[657d728ad44a5017]::util::run_in_thread_with_globals<rustc_interface[657d728ad44a5017]::util::run_in_thread_pool_with_globals<rustc_interface[657d728ad44a5017]::interface::run_compiler<(), rustdoc[535d2b71f692d26c]::main_args::{closure#2}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[77d52d671b80b66]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  27:        0x1114cd3b8 - std::sys::pal::unix::thread::Thread::new::thread_start::h9c1a2a521bb44799
  28:        0x19d93dc0c - __pthread_cond_wait

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-rustdoc&template=ice.md

note: please make sure that you have updated to the latest nightly

note: please attach the file at `/Users/kpreid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/wgpu-types-25.0.0/rustc-ice-2025-04-19T02_38_48-35587.txt` to your bug report

note: compiler flags: --crate-type lib

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack
error: could not document `wgpu-types`

@rustbot label +regression-from-stable-to-nightly

[kpreid]

Minimized to:

/// [`String::`]
pub struct Foo;

@rustbot label -E-needs-mcve

[apiraino]

I've bisected that repro just running it with: rustdoc <somefile.rs>. Bisection seems to point at commit f433fa4

cc @nnethercote and @fee1-dead for #139669

bisected with cargo-bisect-rustc v0.6.9

Host triple: x86_64-unknown-linux-gnu
Reproduce with:

cargo bisect-rustc --without-cargo --preserve --start 1.85.0 --script test.sh 

[apiraino]

Assigning priority (discussion on Zulip).

@rustbot label -I-prioritize +P-medium

[fmease]

cc [@]nnethercote and [@]fmease for [#]139669

mis-ping, I didn't review that one ;-)

[GuillaumeGomez]

Taking a look.

[GuillaumeGomez]

Opened #140052.