thread 'rustc' panicked at 'no entry found for key', src/librustdoc/passes/collect_intra_doc_links.rs:986:16

[jcornaz]

Code

Here is a complete (minimized) reproducer: https://github.com/jcornaz/rustdoc-bug-reproducer

It can be reproduced with a workspace with two crates "a" and "b" where:

• The crate "a" depends on the public (crates.io) crate rapier2d and its code is: pub extern crate rapier2d.
• The crate "b" depends on the workspace crate a and its code is: pub extern crate a; pub use a::*;

With that setup, the command cargo doc rightfully succeeds using the stable toolchain. But fails when using the latest (2022-04-25) nightly toolchain.

Meta

The bug is observable on nightly only (works fine on stable, and beta)

rustc --version --verbose:

rustc 1.62.0-nightly (055bf4ccd 2022-04-25)
binary: rustc
commit-hash: 055bf4ccd521c2c2185166c86951be7be145727c
commit-date: 2022-04-25
host: x86_64-unknown-linux-gnu
release: 1.62.0-nightly
LLVM version: 14.0.1

Error output

thread 'rustc' panicked at 'no entry found for key', src/librustdoc/passes/collect_intra_doc_links.rs:986:16
stack backtrace:
   0:     0x7f7403e9dfbd - std::backtrace_rs::backtrace::libunwind::trace::h255d949666e58f6b
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f7403e9dfbd - std::backtrace_rs::backtrace::trace_unsynchronized::h59be33441d121d1d
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f7403e9dfbd - std::sys_common::backtrace::_print_fmt::h6816fd3d27a9a377
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/sys_common/backtrace.rs:66:5
   3:     0x7f7403e9dfbd - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h82ff7ad0f9b6d219
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/sys_common/backtrace.rs:45:22
   4:     0x7f7403ef9d3c - core::fmt::write::hdc2f5d52c343c037
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/fmt/mod.rs:1194:17
   5:     0x7f7403e8f751 - std::io::Write::write_fmt::h6630625e1b3b8549
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/io/mod.rs:1655:15
   6:     0x7f7403ea0cd5 - std::sys_common::backtrace::_print::h079fc1ab3c6afc34
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/sys_common/backtrace.rs:48:5
   7:     0x7f7403ea0cd5 - std::sys_common::backtrace::print::h15ede9f080adb086
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/sys_common/backtrace.rs:35:9
   8:     0x7f7403ea0cd5 - std::panicking::default_hook::{{closure}}::hab27a4086947747e
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/panicking.rs:295:22
   9:     0x7f7403ea0949 - std::panicking::default_hook::h1c34f54634258465
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/panicking.rs:314:9
  10:     0x7f74046ce631 - rustc_driver[5b352b26ad3dfe5c]::DEFAULT_HOOK::{closure#0}::{closure#0}
  11:     0x7f7403ea14a6 - std::panicking::rust_panic_with_hook::h0dc181d44ee5ed0c
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/panicking.rs:702:17
  12:     0x7f7403ea12a7 - std::panicking::begin_panic_handler::{{closure}}::h875b756428b20e02
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/panicking.rs:588:13
  13:     0x7f7403e9e474 - std::sys_common::backtrace::__rust_end_short_backtrace::hc9cd3566ed60bf46
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/sys_common/backtrace.rs:138:18
  14:     0x7f7403ea0fd9 - rust_begin_unwind
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/panicking.rs:584:5
  15:     0x7f7403e662d3 - core::panicking::panic_fmt::hf36b3eaa51f439da
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/panicking.rs:142:14
  16:     0x7f7403ef69a1 - core::panicking::panic_display::h77d1e09bd8e55215
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/panicking.rs:72:5
  17:     0x7f7403ef694b - core::panicking::panic_str::hafb3b5aec7caf416
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/panicking.rs:56:5
  18:     0x7f7403e66146 - core::option::expect_failed::he734f89dd05e1da9
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/option.rs:1855:5
  19:     0x55ad4c0ab069 - rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::resolve_associated_trait_item
  20:     0x55ad4c0a980e - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector>::resolve_associated_item
  21:     0x55ad4c0a69a5 - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector>::resolve
  22:     0x55ad4c0acda1 - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_item
  23:     0x55ad4c0bf05a - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_inner_recur
  24:     0x55ad4c0b03a2 - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_item
  25:     0x55ad4c0bf0fa - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_inner_recur
  26:     0x55ad4c0b0387 - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_item
  27:     0x55ad4c0bf0fa - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_inner_recur
  28:     0x55ad4c0b0387 - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_item
  29:     0x55ad4c0bf0fa - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_inner_recur
  30:     0x55ad4c0b0387 - <rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::LinkCollector as rustdoc[c740e608ce4065c7]::visit::DocVisitor>::visit_item
  31:     0x55ad4c0a4d3c - rustdoc[c740e608ce4065c7]::passes::collect_intra_doc_links::collect_intra_doc_links
  32:     0x55ad4c119b73 - <rustc_interface[e9d0a11aa8a8a3c0]::passes::QueryContext>::enter::<rustdoc[c740e608ce4065c7]::main_options::{closure#0}::{closure#0}::{closure#1}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>::{closure#0}
  33:     0x55ad4c0f9bd0 - <rustc_interface[e9d0a11aa8a8a3c0]::passes::QueryContext>::enter::<rustdoc[c740e608ce4065c7]::main_options::{closure#0}::{closure#0}::{closure#1}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>
  34:     0x55ad4c04468f - <rustc_interface[e9d0a11aa8a8a3c0]::interface::Compiler>::enter::<rustdoc[c740e608ce4065c7]::main_options::{closure#0}::{closure#0}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>
  35:     0x55ad4becca8a - rustc_span[96ab0c074c70a392]::with_source_map::<core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>, rustc_interface[e9d0a11aa8a8a3c0]::interface::create_compiler_and_run<core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>, rustdoc[c740e608ce4065c7]::main_options::{closure#0}>::{closure#1}>
  36:     0x55ad4c06c4c4 - rustc_interface[e9d0a11aa8a8a3c0]::interface::create_compiler_and_run::<core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>, rustdoc[c740e608ce4065c7]::main_options::{closure#0}>
  37:     0x55ad4becf807 - <scoped_tls[80262534c33ca282]::ScopedKey<rustc_span[96ab0c074c70a392]::SessionGlobals>>::set::<rustdoc[c740e608ce4065c7]::main_args::{closure#0}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>
  38:     0x55ad4c06cc9f - std[e64a7aad70b6f3c5]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[e9d0a11aa8a8a3c0]::util::run_in_thread_pool_with_globals<rustdoc[c740e608ce4065c7]::main_args::{closure#0}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>::{closure#0}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>
  39:     0x55ad4c11c1a9 - <<std[e64a7aad70b6f3c5]::thread::Builder>::spawn_unchecked_<rustc_interface[e9d0a11aa8a8a3c0]::util::run_in_thread_pool_with_globals<rustdoc[c740e608ce4065c7]::main_args::{closure#0}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>::{closure#0}, core[e5e8ff07e69a7713]::result::Result<(), rustc_errors[64e578492efe301e]::ErrorGuaranteed>>::{closure#1} as core[e5e8ff07e69a7713]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  40:     0x7f7403eab3f3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h2990d8a21034a815
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/alloc/src/boxed.rs:1866:9
  41:     0x7f7403eab3f3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h4dfad1b93e043110
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/alloc/src/boxed.rs:1866:9
  42:     0x7f7403eab3f3 - std::sys::unix::thread::Thread::new::thread_start::h62b554408c95900f
                               at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/sys/unix/thread.rs:108:17
  43:     0x7f7403c835c2 - start_thread
  44:     0x7f7403d08584 - __clone
  45:                0x0 - <unknown>

error: internal compiler error: unexpected panic

note: 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: rustc 1.62.0-nightly (055bf4ccd 2022-04-25) running on x86_64-unknown-linux-gnu

note: compiler flags: --crate-type lib

Backtrace

thread 'rustc' panicked at 'no entry found for key', src/librustdoc/passes/collect_intra_doc_links.rs:986:16
stack backtrace:
   0: rust_begin_unwind
             at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/std/src/panicking.rs:584:5
   1: core::panicking::panic_fmt
             at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/panicking.rs:142:14
   2: core::panicking::panic_display
             at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/panicking.rs:72:5
   3: core::panicking::panic_str
             at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/panicking.rs:56:5
   4: core::option::expect_failed
             at /rustc/055bf4ccd521c2c2185166c86951be7be145727c/library/core/src/option.rs:1855:5
   5: rustdoc::passes::collect_intra_doc_links::resolve_associated_trait_item
   6: <rustdoc::passes::collect_intra_doc_links::LinkCollector>::resolve_associated_item
   7: <rustdoc::passes::collect_intra_doc_links::LinkCollector>::resolve
   8: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_item
   9: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_inner_recur
  10: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_item
  11: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_inner_recur
  12: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_item
  13: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_inner_recur
  14: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_item
  15: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_inner_recur
  16: <rustdoc::passes::collect_intra_doc_links::LinkCollector as rustdoc::visit::DocVisitor>::visit_item
  17: rustdoc::passes::collect_intra_doc_links::collect_intra_doc_links
  18: <rustc_interface::passes::QueryContext>::enter::<rustdoc::main_options::{closure#0}::{closure#0}::{closure#1}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#0}
  19: <rustc_interface::passes::QueryContext>::enter::<rustdoc::main_options::{closure#0}::{closure#0}::{closure#1}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>
  20: <rustc_interface::interface::Compiler>::enter::<rustdoc::main_options::{closure#0}::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>
  21: rustc_span::with_source_map::<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_interface::interface::create_compiler_and_run<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustdoc::main_options::{closure#0}>::{closure#1}>
  22: rustc_interface::interface::create_compiler_and_run::<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustdoc::main_options::{closure#0}>
  23: <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustdoc::main_args::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

[petrochenkov]

Fixed in #96447.