Steps to reproduce: 1. Apply the patches at https://github.com/bjorn3/rustc_codegen_cranelift/blob/c03e824db78c83d2c5c37d37c45d2dcc964eca3f/patches to the standard library source. 2. Compile it ``` error[E0432]: unresolved import `core::num::NonZeroI128` --> sysroot_src/src/libstd/num.rs:15:21 | 15 | pub use core::num::{NonZeroI128, NonZeroI16, NonZeroI32, NonZeroI64, NonZeroI8, NonZeroIsize}; | ^^^^^^^^^^^ | | | no `NonZeroI128` in `num` | help: a similar name exists in the module: `NonZeroI8` error[E0432]: unresolved import `core::num::NonZeroU128` --> sysroot_src/src/libstd/num.rs:17:21 | 17 | pub use core::num::{NonZeroU128, NonZeroU16, NonZeroU32, NonZeroU64, NonZeroU8, NonZeroUsize}; | ^^^^^^^^^^^ | | | no `NonZeroU128` in `num` | help: a similar name exists in the module: `NonZeroU8` error[E0412]: cannot find type `AtomicI128` in module `atomic` --> sysroot_src/src/libstd/panic.rs:258:32 | 258 | impl RefUnwindSafe for atomic::AtomicI128 {} | ^^^^^^^^^^ help: a struct with a similar name exists: `AtomicI16` | ::: /home/bjorn/Documenten/cg_clif/build_sysroot/sysroot_src/src/libcore/sync/atomic.rs:1229:9 | 1229 | pub struct $atomic_type { | ----------------------- similarly named struct `AtomicI16` defined here error[E0412]: cannot find type `AtomicU128` in module `atomic` --> sysroot_src/src/libstd/panic.rs:277:32 | 277 | impl RefUnwindSafe for atomic::AtomicU128 {} | ^^^^^^^^^^ help: a struct with a similar name exists: `AtomicU16` | ::: /home/bjorn/Documenten/cg_clif/build_sysroot/sysroot_src/src/libcore/sync/atomic.rs:1229:9 | 1229 | pub struct $atomic_type { | ----------------------- similarly named struct `AtomicU16` defined here thread 'rustc' panicked at 'Failed to get parent for DefId(0:3721 ~ std[c8fe]::panic[0]::{{impl}}[20])', src/librustc_middle/traits/specialization_graph.rs:46:52 stack backtrace: 0: backtrace::backtrace::libunwind::trace at /cargo/registry/src/github.202132.xyz-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/libunwind.rs:86 1: backtrace::backtrace::trace_unsynchronized at /cargo/registry/src/github.202132.xyz-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/mod.rs:66 2: std::sys_common::backtrace::_print_fmt at src/libstd/sys_common/backtrace.rs:78 3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt at src/libstd/sys_common/backtrace.rs:59 4: core::fmt::write at src/libcore/fmt/mod.rs:1069 5: std::io::Write::write_fmt at src/libstd/io/mod.rs:1504 6: std::sys_common::backtrace::_print at src/libstd/sys_common/backtrace.rs:62 7: std::sys_common::backtrace::print at src/libstd/sys_common/backtrace.rs:49 8: std::panicking::default_hook::{{closure}} at src/libstd/panicking.rs:198 9: std::panicking::default_hook at src/libstd/panicking.rs:218 10: rustc_driver::report_ice 11: std::panicking::rust_panic_with_hook at src/libstd/panicking.rs:515 12: rust_begin_unwind at src/libstd/panicking.rs:419 13: std::panicking::begin_panic_fmt at src/libstd/panicking.rs:373 14: rustc_middle::traits::specialization_graph::Graph::parent::{{closure}} 15: rustc_middle::traits::specialization_graph::Graph::parent 16: <rustc_middle::traits::specialization_graph::Ancestors as core::iter::traits::iterator::Iterator>::next 17: rustc_typeck::impl_wf_check::min_specialization::check_min_specialization 18: <rustc_typeck::impl_wf_check::ImplWfCheck as rustc_hir::itemlikevisit::ItemLikeVisitor>::visit_item 19: rustc_middle::hir::map::Map::visit_item_likes_in_module 20: rustc_typeck::impl_wf_check::check_mod_impl_wf 21: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::check_mod_impl_wf>::compute 22: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps 23: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl 24: rustc_query_system::query::plumbing::get_query 25: rustc_query_system::query::plumbing::ensure_query 26: rustc_typeck::impl_wf_check::impl_wf_check 27: rustc_typeck::check_crate 28: rustc_interface::passes::analysis 29: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::analysis>::compute 30: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps 31: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl 32: rustc_query_system::query::plumbing::get_query 33: rustc_middle::ty::context::tls::enter_global 34: rustc_interface::interface::run_compiler_in_existing_thread_pool 35: scoped_tls::ScopedKey<T>::set 36: rustc_ast::attr::with_globals note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace. 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/blob/master/CONTRIBUTING.md#bug-reports note: rustc 1.44.0-nightly (3712e11a8 2020-04-12) running on x86_64-unknown-linux-gnu note: compiler flags: -Z panic-abort-tests -Z codegen-backend=/home/bjorn/Documenten/cg_clif/target/release/librustc_codegen_cranelift.so -Z force-unstable-if-unmarked -C prefer-dynamic -C debuginfo=2 -C incremental -C linker=aarch64-linux-gnu-gcc -C panic=abort -C debuginfo=2 --crate-type dylib --crate-type rlib note: some of the compiler flags provided by cargo are hidden query stack during panic: #0 [check_mod_impl_wf] checking that impls are well-formed in module `panic` #1 [analysis] running analysis passes on this crate end of query stack error: aborting due to 4 previous errors ``` (keep alive: https://github.com/bjorn3/rustc_codegen_cranelift/commit/c03e824db78c83d2c5c37d37c45d2dcc964eca3f)