Rustdoc nightly crash with "Cannot create local mono-item"

[mattheww]

Current nightly rust is crashing for me if I try to build the documentation of
cortex-m-rt with opt-level = "s".

The reported error is:

error: internal compiler error: src/librustc_mir/monomorphize/collector.rs:745: Cannot create local mono-item for DefId(5/0:10 ~ r0[6302]::zero_bss[0])

The version is rustdoc 1.35.0-nightly (f22dca0a1 2019-03-05).

I haven't been able to show a problem using cargo +nightly build.

Steps to reproduce:

cargo init bugreport
cd bugreport
cat >> Cargo.toml <<EOF
cortex-m-rt = "0.6.7"

[profile.dev]
opt-level = "s"
EOF

RUST_BACKTRACE=1 cargo +nightly doc

backtrace:

thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:620:9
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
   1: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:71
   2: std::panicking::default_hook::{{closure}}
             at src/libstd/sys_common/backtrace.rs:59
             at src/libstd/panicking.rs:197
   3: std::panicking::default_hook
             at src/libstd/panicking.rs:211
   4: rustc::util::common::panic_hook
   5: core::ops::function::Fn::call
   6: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:478
   7: std::panicking::begin_panic
   8: rustc_errors::Handler::bug
   9: rustc::util::bug::opt_span_bug_fmt::{{closure}}
  10: rustc::ty::context::tls::with_opt::{{closure}}
  11: rustc::ty::context::tls::with_context_opt
  12: rustc::ty::context::tls::with_opt
  13: rustc::util::bug::opt_span_bug_fmt
  14: rustc::util::bug::bug_fmt
  15: rustc_mir::monomorphize::collector::should_monomorphize_locally
  22: rustc_mir::monomorphize::collector::collect_crate_mono_items
  27: rustc::dep_graph::graph::DepGraph::with_task_impl
  28: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::get_query
  29: core::ops::function::FnOnce::call_once
  30: rustc::ty::query::__query_compute::backend_optimization_level
  31: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors<'tcx> for rustc::ty::query::queries::backend_optimization_level<'tcx>>::compute
  32: rustc::dep_graph::graph::DepGraph::with_task_impl
  33: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::get_query
  34: rustc_codegen_llvm::back::write::create_target_machine
  35: rustc_codegen_llvm::context::create_module
  36: rustc_codegen_ssa::base::codegen_crate
  37: <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_utils::codegen_backend::CodegenBackend>::codegen_crate
  38: rustc::util::common::time
  39: rustc_driver::driver::phase_4_codegen
  40: <std::thread::local::LocalKey<T>>::with
  41: rustc::ty::context::TyCtxt::create_and_enter
  42: rustc_driver::driver::compile_input
  43: rustc_driver::run_compiler_with_pool
  44: <scoped_tls::ScopedKey<T>>::set
  45: rustc_driver::run_compiler
  46: syntax::with_globals
  47: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:87
  49: std::sys::unix::thread::Thread::new::thread_start
             at /rustc/f22dca0a1bef4141e75326caacc3cd59f3d5be8e/src/liballoc/boxed.rs:759
             at src/libstd/sys_common/thread.rs:14
             at src/libstd/sys/unix/thread.rs:80
  50: start_thread
  51: __clone
query stack during panic:
#0 [collect_and_partition_mono_items] collect_and_partition_mono_items
#1 [backend_optimization_level] optimization level used by backend
end of query stack
error: aborting due to previous error

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.35.0-nightly (f22dca0a1 2019-03-05) running on i686-unknown-linux-gnu

note: compiler flags: -C opt-level=s -C debuginfo=2 -C debug-assertions=on --crate-type lib

[jonas-schievink]

Based on the backtrace this looks like a duplicate of #58323, so closing in favor of that. This will be fixed by #58605