rustc segmentation fault

[Volker-Weissmann]

TLDR: rustc segfaults if you compile autocxx:

$ rustc --version --verbose
rustc 1.51.0-nightly (44e3daf 2020-12-31)
binary: rustc
commit-hash: 44e3daf
commit-date: 2020-12-31
host: x86_64-unknown-linux-gnu
release: 1.51.0-nightly
rustc 1.51.0-nightly (44e3daf 2020-12-31)
$ cargo --version --verbose
cargo 1.50.0-nightly (75d5d8cff 2020-12-22)
release: 1.50.0
commit-hash: 75d5d8cffe3464631f82dcd3c470b78dc1dda8bb
commit-date: 2020-12-22
$ git clone https://github.com/google/autocxx --depth 1
$ cd autocxx/demo
$ cargo build
...
error: could not compile autocxx-demo

Caused by:
process didn't exit successfully: rustc --crate-name autocxx_demo --edition=2018 demo/src/main.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 -C metadata=16aa58ac615e31ca -C extra-filename=-16aa58ac615e31ca --out-dir /home/volker/cloned/autocxx/target/debug/deps -C incremental=/home/volker/cloned/autocxx/target/debug/incremental -L dependency=/home/volker/cloned/autocxx/target/debug/deps --extern autocxx=/home/volker/cloned/autocxx/target/debug/deps/libautocxx-5764a21f2c081756.rlib --extern cxx=/home/volker/cloned/autocxx/target/debug/deps/libcxx-5e5d0b573d59c1d9.rlib -L native=/home/volker/cloned/autocxx/target/debug/build/autocxx-demo-c59a4d655bdad450/out -l static=autocxx-demo -l stdc++ -L native=/home/volker/cloned/autocxx/target/debug/build/cxx-b7e40aeaf705160f/out -L native=/home/volker/cloned/autocxx/target/debug/build/link-cplusplus-de28d3bdd966afa5/out (signal: 11, SIGSEGV: invalid memory reference)

[SNCPlay42]

Backtrace

#0  0x00007f7b7a13d42e in llvm::orc::NullLegacyResolver::findSymbolInLogicalDylib(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) () from /usr/lib/../lib/libLLVM-11.so
#1  0x00007f7b964702de in call_init.part () from /lib64/ld-linux-x86-64.so.2
#2  0x00007f7b964703c8 in _dl_init () from /lib64/ld-linux-x86-64.so.2
#3  0x00007f7b9168a0e5 in _dl_catch_exception () from /usr/lib/libc.so.6
#4  0x00007f7b96474705 in dl_open_worker () from /lib64/ld-linux-x86-64.so.2
#5  0x00007f7b9168a088 in _dl_catch_exception () from /usr/lib/libc.so.6
#6  0x00007f7b96473f3e in _dl_open () from /lib64/ld-linux-x86-64.so.2
#7  0x00007f7b9171b34c in ?? () from /usr/lib/libdl.so.2
#8  0x00007f7b9168a088 in _dl_catch_exception () from /usr/lib/libc.so.6
#9  0x00007f7b9168a153 in _dl_catch_error () from /usr/lib/libc.so.6
#10 0x00007f7b9171bb89 in ?? () from /usr/lib/libdl.so.2
#11 0x00007f7b9171b3d8 in dlopen () from /usr/lib/libdl.so.2
#12 0x00007f7b84e1fb38 in libloading::os::unix::{{impl}}::open::{{closure}}<&std::path::PathBuf> () at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/libloading-0.6.6/src/os/unix/mod.rs:149
#13 0x00007f7b84e0f977 in libloading::os::unix::with_dlerror<libloading::os::unix::Library,closure-1> (wrap=0x7f7b84ddf950 <core::ops::function::FnOnce::call_once<closure-0,(libloading::error::DlDescription)>>, closure=...)
    at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/libloading-0.6.6/src/os/unix/mod.rs:55
#14 0x00007f7b84e1f9bc in libloading::os::unix::Library::open<&std::path::PathBuf> (filename=..., flags=2) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/libloading-0.6.6/src/os/unix/mod.rs:147
#15 0x00007f7b84e1f795 in libloading::os::unix::Library::new<&std::path::PathBuf> (filename=0x7f7b8bfd6448) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/libloading-0.6.6/src/os/unix/mod.rs:111
#16 0x00007f7b84ec1173 in libloading::Library::new<&std::path::PathBuf> (filename=0x7f7b8bfd6448) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/libloading-0.6.6/src/lib.rs:131
#17 0x00007f7b84d83120 in clang_sys::load_manually () at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/clang-sys-1.0.3/src/link.rs:198
#18 0x00007f7b84d84b43 in clang_sys::load () at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/clang-sys-1.0.3/src/link.rs:224
#19 0x00007f7b849e469f in autocxx_bindgen::ensure_libclang_is_loaded::{{impl}}::deref::__static_ref_initialize () at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/autocxx-bindgen-0.56.1/src/lib.rs:1922
#20 core::ops::function::FnOnce::call_once<fn() -> alloc::sync::Arc<clang_sys::SharedLibrary>,()> () at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:227
#21 0x00007f7b8491cb07 in lazy_static::lazy::{{impl}}::get::{{closure}}<alloc::sync::Arc<clang_sys::SharedLibrary>,fn() -> alloc::sync::Arc<clang_sys::SharedLibrary>> ()
    at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/lazy_static-1.4.0/src/inline_lazy.rs:31
#22 0x00007f7b849e35ef in std::sync::once::{{impl}}::call_once::{{closure}}<closure-0> () at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sync/once.rs:261
#23 0x00007f7b9180dff2 in std::sync::once::Once::call_inner () at library/std/src/sync/once.rs:419
#24 0x00007f7b849e3445 in std::sync::once::Once::call_once<closure-0> (self=0x7f7b856cf218 <<autocxx_bindgen::ensure_libclang_is_loaded::LIBCLANG as core::ops::deref::Deref>::deref::__stability::LAZY+8>, f=...)
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sync/once.rs:261
#25 0x00007f7b84a0ad29 in lazy_static::lazy::Lazy<alloc::sync::Arc<clang_sys::SharedLibrary>>::get<alloc::sync::Arc<clang_sys::SharedLibrary>,fn() -> alloc::sync::Arc<clang_sys::SharedLibrary>> (
    self=0x7f7b856cf210 <<autocxx_bindgen::ensure_libclang_is_loaded::LIBCLANG as core::ops::deref::Deref>::deref::__stability::LAZY>, f=<optimized out>) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/lazy_static-1.4.0/src/inline_lazy.rs:30
#26 autocxx_bindgen::ensure_libclang_is_loaded::{{impl}}::deref::__stability () at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/lazy_static-1.4.0/src/lib.rs:142
#27 autocxx_bindgen::ensure_libclang_is_loaded::{{impl}}::deref (self=0x7f7b852c497a) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/lazy_static-1.4.0/src/lib.rs:144
#28 0x00007f7b84a01208 in autocxx_bindgen::ensure_libclang_is_loaded () at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/autocxx-bindgen-0.56.1/src/lib.rs:1930
#29 0x00007f7b84a017cd in autocxx_bindgen::Bindings::generate (options=...) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/autocxx-bindgen-0.56.1/src/lib.rs:1988
#30 0x00007f7b849fe106 in autocxx_bindgen::Builder::generate (self=...) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/autocxx-bindgen-0.56.1/src/lib.rs:1335
#31 0x00007f7b8459d8e7 in autocxx_engine::IncludeCpp::generate (self=0x7f7b8bfea5e8) at engine/src/lib.rs:377
#32 0x00007f7b8457f519 in autocxx_macro::include_cpp_impl::{{closure}} () at macro/src/lib.rs:25
#33 0x00007f7b8457f8af in std::panic::{{impl}}::call_once<proc_macro::TokenStream,closure-0> (self=..., _args=()) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panic.rs:322
#34 0x00007f7b84583bb0 in std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure-0>,proc_macro::TokenStream> (data=0x7f7b8bfeaf10) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:381
#35 0x00007f7b84583d3d in __rust_try () from /tmp/autocxx/target/debug/deps/libautocxx_macro-4e0e6644536281ef.so
#36 0x00007f7b84583906 in std::panicking::try<proc_macro::TokenStream,std::panic::AssertUnwindSafe<closure-0>> (f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:345
#37 0x00007f7b8457f938 in std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure-0>,proc_macro::TokenStream> (f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panic.rs:396
#38 0x00007f7b8457d4d0 in proc_macro_error::entry_point<std::panic::AssertUnwindSafe<closure-0>> (f=..., proc_macro_hack=false) at ~/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/proc-macro-error-1.0.4/src/lib.rs:432
#39 0x00007f7b8457df0b in autocxx_macro::include_cpp_impl (input=...) at macro/src/lib.rs:21
#40 0x00007f7b8457f015 in core::ops::function::FnOnce::call_once<fn(proc_macro::TokenStream) -> proc_macro::TokenStream,(proc_macro::TokenStream)> ()
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:227
#41 0x00007f7b84584d06 in proc_macro::bridge::client::{{impl}}::expand1::run::{{closure}}<fn(proc_macro::TokenStream) -> proc_macro::TokenStream> (input=...)
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:411
#42 0x00007f7b84584363 in proc_macro::bridge::client::run_client::{{closure}}::{{closure}}<proc_macro::bridge::client::TokenStream,proc_macro::bridge::client::TokenStream,closure-0> ()
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:377
#43 0x00007f7b84580888 in proc_macro::bridge::scoped_cell::{{impl}}::set::{{closure}}<proc_macro::bridge::client::BridgeStateL,(),closure-0> ()
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/scoped_cell.rs:81
#44 0x00007f7b84580a9d in proc_macro::bridge::scoped_cell::ScopedCell<proc_macro::bridge::client::BridgeStateL>::replace<proc_macro::bridge::client::BridgeStateL,(),closure-0> (self=0x7f7b8bffdb68, replacement=..., f=...)
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/scoped_cell.rs:76
#45 0x00007f7b84580861 in proc_macro::bridge::scoped_cell::ScopedCell<proc_macro::bridge::client::BridgeStateL>::set<proc_macro::bridge::client::BridgeStateL,(),closure-0> (self=0x7f7b8bffdb68, value=..., f=...)
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/scoped_cell.rs:81
#46 0x00007f7b84584acf in proc_macro::bridge::client::{{impl}}::enter::{{closure}}<(),closure-0> (state=0x7f7b8bffdb68) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:325
#47 0x00007f7b84582acd in std::thread::local::LocalKey<proc_macro::bridge::scoped_cell::ScopedCell<proc_macro::bridge::client::BridgeStateL>>::try_with<proc_macro::bridge::scoped_cell::ScopedCell<proc_macro::bridge::client::BridgeStateL>,closure-1,()> (
    self=0x7f7b85614aa0, f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/thread/local.rs:272
#48 0x00007f7b8458262d in std::thread::local::LocalKey<proc_macro::bridge::scoped_cell::ScopedCell<proc_macro::bridge::client::BridgeStateL>>::with<proc_macro::bridge::scoped_cell::ScopedCell<proc_macro::bridge::client::BridgeStateL>,closure-1,()> (
    self=0x7f7b85614aa0, f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/thread/local.rs:248
#49 0x00007f7b8457e72d in proc_macro::bridge::Bridge::enter<(),closure-0> (self=..., f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:325
#50 0x00007f7b84584254 in proc_macro::bridge::client::run_client::{{closure}}<proc_macro::bridge::client::TokenStream,proc_macro::bridge::client::TokenStream,closure-0> ()
    at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:370
#51 0x00007f7b8457f902 in std::panic::{{impl}}::call_once<(),closure-0> (self=..., _args=()) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panic.rs:322
#52 0x00007f7b84583b60 in std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure-0>,()> (data=0x7f7b8bfebac8) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:381
#53 0x00007f7b84583d3d in __rust_try () from /tmp/autocxx/target/debug/deps/libautocxx_macro-4e0e6644536281ef.so
#54 0x00007f7b84583a80 in std::panicking::try<(),std::panic::AssertUnwindSafe<closure-0>> (f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:345
#55 0x00007f7b8457f982 in std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure-0>,()> (f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panic.rs:396
#56 0x00007f7b845840ac in proc_macro::bridge::client::run_client<proc_macro::bridge::client::TokenStream,proc_macro::bridge::client::TokenStream,closure-0> (bridge=..., f=...) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:369
#57 0x00007f7b84584cc1 in proc_macro::bridge::client::{{impl}}::expand1::run<fn(proc_macro::TokenStream) -> proc_macro::TokenStream> (bridge=..., f=0x7f7b8457dee0 <autocxx_macro::include_cpp_impl>) at ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:411
#58 0x00007f7b9414deb4 in proc_macro::bridge::server::run_server () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#59 0x00007f7b940ba011 in <rustc_expand::proc_macro::BangProcMacro as rustc_expand::base::ProcMacro>::expand () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#60 0x00007f7b9408132b in rustc_expand::expand::MacroExpander::fully_expand_fragment () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#61 0x00007f7b9407f6e8 in rustc_expand::expand::MacroExpander::expand_crate () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#62 0x00007f7b922e3a36 in rustc_session::utils::<impl rustc_session::session::Session>::time () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#63 0x00007f7b9232fc52 in rustc_interface::passes::configure_and_expand_inner () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#64 0x00007f7b922bf475 in rustc_interface::passes::configure_and_expand::_$u7b$$u7b$closure$u7d$$u7d$::h2410401d2ea7094a () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#65 0x00007f7b922b60cf in rustc_data_structures::box_region::PinnedGenerator<I,A,R>::new () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#66 0x00007f7b9232ebe6 in rustc_interface::passes::configure_and_expand () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#67 0x00007f7b92358c2b in rustc_interface::queries::Queries::expansion () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#68 0x00007f7b92105c85 in rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#69 0x00007f7b920f3cae in rustc_span::with_source_map () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#70 0x00007f7b92106f52 in rustc_interface::interface::create_compiler_and_run () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#71 0x00007f7b920f485a in rustc_span::with_session_globals () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#72 0x00007f7b9210d04f in std::sys_common::backtrace::__rust_begin_short_backtrace () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#73 0x00007f7b920747f8 in core::ops::function::FnOnce::call_once{{vtable-shim}} () from ~/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/bin/../lib/librustc_driver-74849affecce5bb0.so
#74 0x00007f7b9182352a in alloc::boxed::{{impl}}::call_once<(),FnOnce<()>,alloc::alloc::Global> () at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/alloc/src/boxed.rs:1307
#75 alloc::boxed::{{impl}}::call_once<(),alloc::boxed::Box<FnOnce<()>, alloc::alloc::Global>,alloc::alloc::Global> () at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/alloc/src/boxed.rs:1307
#76 std::sys::unix::thread::{{impl}}::new::thread_start () at library/std/src/sys/unix/thread.rs:71
#77 0x00007f7b917343e9 in start_thread () from /usr/lib/libpthread.so.0
#78 0x00007f7b9164f293 in clone () from /usr/lib/libc.so.6

Possibly not a rustc bug - the segfault comes from autocxx's proc macros trying to load LLVM (through clang). Nevertheless, this works on 1.48 and crashes on 1.49. Maybe rustc's LLVM and clang's LLVM are clashing when loaded in the same process?

@rustbot label I-crash A-llvm regression-from-stable-to-stable

[apiraino]

@rustbot ping llvm

[rustbot]

Hey LLVM ICE-breakers! This bug has been identified as a good
"LLVM ICE-breaking candidate". In case it's useful, here are some
instructions for tackling these sorts of bugs. Maybe take a look?
Thanks! <3

cc @camelid @comex @cuviper @DutchGhost @hdhoang @heyrutvik @higuoxing @JOE1994 @jryans @mmilenko @nagisa @nikic @Noah-Kennedy @SiavoshZarrasvand @spastorino @vertexclique

[nagisa]

Maybe rustc's LLVM and clang's LLVM are clashing when loaded in the same process

Very plausible given that it crashes during the early initialization of the libLLVM dynamic library! I'd report this issue against the relevant repository(-ies) – autocxx and maybe clang_sys. They are better served to investigate why the LLVM they load is crashing during initialization.

Thanks for obtaining the backtrace @SNCPlay42!

[cuviper]

Maybe rustc's LLVM and clang's LLVM are clashing when loaded in the same process?

That sounds a lot like #76980. The problems there are more general libstdc++ conflicts with C++ proc-macros, but I could certainly see multiple LLVMs raising this problem to a larger extent. I doubt that's something we could support.

[adetaylor]

Thanks for all the comments and diagnosis here everyone. Over in autocxx, I already concluded that loading llvm in a procedural macro was excessively Bold, and google/autocxx#51 is a plan eventually to fix that. Sounds like I might need to accelerate it :)

[nagisa]

It has been a long-standing goal to run procedural macros in a separate process as well as about giving more meaningful error messages when procedural macros fail. That would also fix this as a side effect. I'm sure both ideas have their own issues somewhere as well if you're interested in keeping eye out of how these pan out.