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Optimize `checked_ilog` and `pow` when `base` is a power of two
r? @scottmcm
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The job aarch64-gnu-llvm-20-2 failed! Check out the build log: (web) (plain enhanced) (plain)
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note: no errors encountered even though delayed bugs were created
note: those delayed bugs will now be shown as internal compiler errors
error: internal compiler error: alignment greater than 2^29 should be errored on elsewhere
##[error] --> example/mini_core_hello_world.rs:359:12
|
359 | #[repr(align(8192))]
| ^^^^^^^^^^^
|
---
3: <rustc_errors::diagnostic::Diag>::emit_producing_error_guaranteed
4: <rustc_errors::DiagCtxtHandle>::span_delayed_bug::<rustc_span::span_encoding::Span, &str>
5: <rustc_passes::check_attr::CheckAttrVisitor>::check_attributes
6: <rustc_passes::check_attr::CheckAttrVisitor as rustc_hir::intravisit::Visitor>::visit_item
7: <rustc_middle::ty::context::TyCtxt>::hir_visit_item_likes_in_module::<rustc_passes::check_attr::CheckAttrVisitor>
8: rustc_passes::check_attr::check_mod_attrs
9: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_mod_attrs::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
10: <rustc_query_impl::query_impl::check_mod_attrs::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_span::def_id::LocalModDefId)>>::call_once
11: <std::thread::local::LocalKey<core::cell::Cell<*const ()>>>::with::<rustc_middle::ty::context::tls::enter_context<rustc_query_system::query::plumbing::try_load_from_disk_and_cache_in_memory<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 0]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt>::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
12: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::LocalModDefId, rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
13: rustc_query_impl::query_impl::check_mod_attrs::get_query_non_incr::__rust_end_short_backtrace
14: <rustc_middle::ty::context::TyCtxt>::par_hir_for_each_module::<rustc_interface::passes::run_required_analyses::{closure#0}::{closure#1}::{closure#0}::{closure#2}::{closure#0}>::{closure#0}
15: <rustc_data_structures::sync::parallel::ParallelGuard>::run::<(), rustc_interface::passes::run_required_analyses::{closure#0}::{closure#0}::{closure#1}>
16: rustc_interface::passes::analysis
17: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
18: <rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, ())>>::call_once
19: <std::thread::local::LocalKey<core::cell::Cell<*const ()>>>::with::<rustc_middle::ty::context::tls::enter_context<rustc_query_system::query::plumbing::execute_job_non_incr<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt>::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
20: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
21: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
22: <std::thread::local::LocalKey<core::cell::Cell<*const ()>>>::with::<rustc_middle::ty::context::tls::enter_context<<rustc_middle::ty::context::GlobalCtxt>::enter<rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}, core::option::Option<rustc_interface::queries::Linker>>::{closure#1}, core::option::Option<rustc_interface::queries::Linker>>::{closure#0}, core::option::Option<rustc_interface::queries::Linker>>
23: <rustc_middle::ty::context::TyCtxt>::create_global_ctxt::<core::option::Option<rustc_interface::queries::Linker>, rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}>
24: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
25: <alloc::boxed::Box<dyn for<'a> core::ops::function::FnOnce<(&'a rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &'a std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt<'a>>, &'a rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena<'a>>, &'a rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena<'a>>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}), Output = core::option::Option<rustc_interface::queries::Linker>>> as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once
26: rustc_interface::passes::create_and_enter_global_ctxt::<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>
27: <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>
28: rustc_span::create_session_globals_then::<(), rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}::{closure#0}>
29: std::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
30: <<std::thread::Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
---
warning: the ICE couldn't be written to `/checkout/compiler/rustc_codegen_cranelift/rustc-ice-2025-10-02T02_02_05-34620.txt`: Read-only file system (os error 30)
note: rustc 1.92.0-nightly (ba891baca 2025-10-02) running on aarch64-unknown-linux-gnu
note: compiler flags: -C panic=abort -Z panic-abort-tests -Z codegen-backend=cranelift -C symbol-mangling-version=v0 -Z randomize-layout -Z unstable-options -Z macro-backtrace -C split-debuginfo=off -C link-arg=-L/usr/lib/llvm-20/lib -C llvm-args=-import-instr-limit=10 -C link-args=-Wl,-z,origin -C link-args=-Wl,-rpath,$ORIGIN/../lib -C debuginfo=2 -C panic=abort -Z force-unstable-if-unmarked
query stack during panic:
end of query stack
"/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustc-clif" "-Csymbol-mangling-version=v0" "-Zrandomize-layout" "-Zunstable-options" "--check-cfg=cfg(bootstrap)" "-Zmacro-backtrace" "-Csplit-debuginfo=off" "-Clink-arg=-L/usr/lib/llvm-20/lib" "-Cllvm-args=-import-instr-limit=10" "-Clink-args=-Wl,-z,origin" "-Clink-args=-Wl,-rpath,$ORIGIN/../lib" "-Alinker-messages" "-L" "crate=/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/example" "--out-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/example" "-Cdebuginfo=2" "--target" "aarch64-unknown-linux-gnu" "-Cpanic=abort" "--check-cfg=cfg(jit)" "example/mini_core_hello_world.rs" exited with status ExitStatus(unix_wait_status(25856))
Command `/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo run --target aarch64-unknown-linux-gnu -Zbinary-dep-depinfo -j 4 -Zroot-dir=/checkout --locked --color always --release --manifest-path /checkout/compiler/rustc_codegen_cranelift/build_system/Cargo.toml -- test --download-dir /checkout/obj/build/cg_clif_download --out-dir /checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif --no-unstable-features --use-backend cranelift --sysroot llvm --skip-test testsuite.extended_sysroot [workdir=/checkout/compiler/rustc_codegen_cranelift]` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/test.rs:3658:25
Executed at: src/bootstrap/src/core/build_steps/test.rs:3703:26
Command has failed. Rerun with -v to see more details.
Bootstrap failed while executing `--stage 2 test --skip tests --skip coverage-map --skip coverage-run --skip library --skip tidyselftest`
Build completed unsuccessfully in 0:22:45
local time: Thu Oct 2 02:02:05 UTC 2025
network time: Thu, 02 Oct 2025 02:02:05 GMT
##[error]Process completed with exit code 1.
does this affect the codegen in practical circumstances? I would expect even a fairly weak optimizer to perform this optimization, making us hand-coding it irrelevant and potentially even harmful because we introduce more conditional logic to chew through.
does this affect the codegen in practical circumstances?
It replaces a loop by some bit manipulations. Whether anyone actually calls either function with a compile-time known, power of 2 base is another question. But it can't hurt, since it is guarded by is_statically_known.
I would expect even a fairly weak optimizer to perform this optimization, making us hand-coding it irrelevant
No, in either function, LLVM is not able to see that the loop is performing a log/pow and apply the identities: https://godbolt.org/z/6vMsxc9Kh
and potentially even harmful because we introduce more conditional logic to chew through.
They're guarded by is_statically_known so will be ignored if the base is not known at compile-time
No, in either function, LLVM is not able to see that the loop is performing a log/pow and apply the identities: https://godbolt.org/z/6vMsxc9Kh
...then I'm kinda surprised! Nice catch.
does this affect the codegen in practical circumstances?
Would be good to have codegen tests to demonstrate what this is doing -- especially since that way there's a way for people to try removing the special cases later if they think that LLVM no longer needs them.
This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed.
Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.
The job pr-check-2 failed! Check out the build log: (web) (plain enhanced) (plain)
Click to see the possible cause of the failure (guessed by this bot)
[RUSTC-TIMING] std test:true 99.755
error: cannot test inner items
--> library/coretests/tests/num/uint_macros.rs:314:17
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
314 | | #[test]
| | ^^^^^^^ in this attribute macro expansion (#2)
... |
626 | | };
---
| -------------- in this expansion of `#[test]` (#2)
|
::: library/coretests/tests/num/u128.rs:1:1
|
1 | uint_module!(u128);
| ------------------ in this macro invocation (#1)
|
= note: `-D unnameable-test-items` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(unnameable_test_items)]`
error: cannot test inner items
--> library/coretests/tests/num/uint_macros.rs:314:17
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
314 | | #[test]
| | ^^^^^^^ in this attribute macro expansion (#2)
... |
626 | | };
---
| -------------- in this expansion of `#[test]` (#2)
|
::: library/coretests/tests/num/u128.rs:1:1
|
1 | uint_module!(u128);
| ------------------ in this macro invocation (#1)
error: cannot test inner items
--> library/coretests/tests/num/uint_macros.rs:314:17
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
314 | | #[test]
| | ^^^^^^^ in this attribute macro expansion (#2)
... |
626 | | };
---
| -------------- in this expansion of `#[test]` (#2)
|
::: library/coretests/tests/num/u16.rs:1:1
|
1 | uint_module!(u16);
| ----------------- in this macro invocation (#1)
error: cannot test inner items
--> library/coretests/tests/num/uint_macros.rs:314:17
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
314 | | #[test]
| | ^^^^^^^ in this attribute macro expansion (#2)
... |
626 | | };
---
| -------------- in this expansion of `#[test]` (#2)
|
::: library/coretests/tests/num/u32.rs:1:1
|
1 | uint_module!(u32);
| ----------------- in this macro invocation (#1)
error: cannot test inner items
--> library/coretests/tests/num/uint_macros.rs:314:17
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
314 | | #[test]
| | ^^^^^^^ in this attribute macro expansion (#2)
... |
626 | | };
---
| -------------- in this expansion of `#[test]` (#2)
|
::: library/coretests/tests/num/u64.rs:1:1
|
1 | uint_module!(u64);
| ----------------- in this macro invocation (#1)
error: cannot test inner items
--> library/coretests/tests/num/uint_macros.rs:314:17
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
314 | | #[test]
| | ^^^^^^^ in this attribute macro expansion (#2)
... |
626 | | };
---
| -------------- in this expansion of `#[test]` (#2)
|
::: library/coretests/tests/num/u8.rs:1:1
|
1 | uint_module!(u8);
| ---------------- in this macro invocation (#1)
[RUSTC-TIMING] sync test:true 43.836
error: function `test_pow_overflow` is never used
--> library/coretests/tests/num/uint_macros.rs:316:20
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
316 | | fn test_pow_overflow() {
| | ^^^^^^^^^^^^^^^^^
... |
626 | | };
627 | | }
| |_- in this expansion of `uint_module!`
|
::: library/coretests/tests/num/u128.rs:1:1
|
1 | uint_module!(u128);
| ------------------ in this macro invocation
|
= note: `-D dead-code` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(dead_code)]`
error: function `test_pow_overflow` is never used
--> library/coretests/tests/num/uint_macros.rs:316:20
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
316 | | fn test_pow_overflow() {
| | ^^^^^^^^^^^^^^^^^
... |
626 | | };
627 | | }
| |_- in this expansion of `uint_module!`
|
::: library/coretests/tests/num/u16.rs:1:1
|
1 | uint_module!(u16);
| ----------------- in this macro invocation
error: function `test_pow_overflow` is never used
--> library/coretests/tests/num/uint_macros.rs:316:20
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
316 | | fn test_pow_overflow() {
| | ^^^^^^^^^^^^^^^^^
... |
626 | | };
627 | | }
| |_- in this expansion of `uint_module!`
|
::: library/coretests/tests/num/u32.rs:1:1
|
1 | uint_module!(u32);
| ----------------- in this macro invocation
error: function `test_pow_overflow` is never used
--> library/coretests/tests/num/uint_macros.rs:316:20
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
316 | | fn test_pow_overflow() {
| | ^^^^^^^^^^^^^^^^^
... |
626 | | };
627 | | }
| |_- in this expansion of `uint_module!`
|
::: library/coretests/tests/num/u64.rs:1:1
|
1 | uint_module!(u64);
| ----------------- in this macro invocation
error: function `test_pow_overflow` is never used
--> library/coretests/tests/num/uint_macros.rs:316:20
|
1 | / macro_rules! uint_module {
2 | | ($T:ident) => {
3 | | use core::num::ParseIntError;
4 | | use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
... |
316 | | fn test_pow_overflow() {
| | ^^^^^^^^^^^^^^^^^
... |
626 | | };
627 | | }
| |_- in this expansion of `uint_module!`
|
::: library/coretests/tests/num/u8.rs:1:1
|
1 | uint_module!(u8);
| ---------------- in this macro invocation
[RUSTC-TIMING] alloctests test:true 104.670
[RUSTC-TIMING] coretests test:true 85.406
error: could not compile `coretests` (test "coretests") due to 15 previous errors
The job x86_64-gnu-gcc failed! Check out the build log: (web) (plain enhanced) (plain)
Click to see the possible cause of the failure (guessed by this bot)
For more information how to resolve CI failures of this job, visit this link.
This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.
Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.
The job aarch64-gnu-llvm-20-2 failed! Check out the build log: (web) (plain enhanced) (plain)
Click to see the possible cause of the failure (guessed by this bot)
num::u8::strict_pow
test result: FAILED. 2253 passed; 10 failed; 6 ignored; 0 measured; 0 filtered out; finished in 3.73s
error: test failed, to rerun pass `-p coretests --test coretests`
env -u RUSTC_WRAPPER CARGO_ENCODED_RUSTDOCFLAGS="-Csymbol-mangling-version=v0\u{1f}-Zannotate-moves\u{1f}-Zrandomize-layout\u{1f}-Zunstable-options\u{1f}--check-cfg=cfg(bootstrap)\u{1f}-Dwarnings\u{1f}-Wrustdoc::invalid_codeblock_attributes\u{1f}--crate-version\u{1f}1.93.0-nightly\t(b37825bd9\t2025-11-22)" CARGO_ENCODED_RUSTFLAGS="-Csymbol-mangling-version=v0\u{1f}-Zannotate-moves\u{1f}-Zrandomize-layout\u{1f}-Zunstable-options\u{1f}--check-cfg=cfg(bootstrap)\u{1f}-Zmacro-backtrace\u{1f}-Csplit-debuginfo=off\u{1f}-Clink-arg=-L/usr/lib/llvm-20/lib\u{1f}-Cllvm-args=-import-instr-limit=10\u{1f}-Clink-args=-Wl,-z,origin\u{1f}-Clink-args=-Wl,-rpath,$ORIGIN/../lib\u{1f}-Alinker-messages\u{1f}--cap-lints=allow\u{1f}--cfg\u{1f}randomized_layouts" RUSTC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustc-clif" RUSTDOC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustdoc-clif" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo" "test" "--manifest-path" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/sysroot_tests/Cargo.toml" "--target-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/sysroot_tests_target" "--locked" "--target" "aarch64-unknown-linux-gnu" "-p" "coretests" "-p" "alloctests" "--tests" "--" "-q" exited with status ExitStatus(unix_wait_status(25856))
Bootstrap failed while executing `--stage 2 test --skip tests --skip coverage-map --skip coverage-run --skip library --skip tidyselftest`
Command `/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo run --target aarch64-unknown-linux-gnu -Zbinary-dep-depinfo -j 4 -Zroot-dir=/checkout --locked --color always --release --manifest-path /checkout/compiler/rustc_codegen_cranelift/build_system/Cargo.toml -- test --download-dir /checkout/obj/build/cg_clif_download --out-dir /checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif --no-unstable-features --use-backend cranelift --sysroot llvm --skip-test testsuite.extended_sysroot [workdir=/checkout/compiler/rustc_codegen_cranelift]` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/test.rs:3723:25
Executed at: src/bootstrap/src/core/build_steps/test.rs:3768:26
Command has failed. Rerun with -v to see more details.
Build completed unsuccessfully in 0:28:00
local time: Sat Nov 22 02:04:58 UTC 2025
network time: Sat, 22 Nov 2025 02:04:59 GMT
##[error]Process completed with exit code 1.
##[group]Run echo "disk usage:"
The job aarch64-gnu-llvm-20-2 failed! Check out the build log: (web) (plain enhanced) (plain)
Click to see the possible cause of the failure (guessed by this bot)
num::u8::strict_pow
test result: FAILED. 2253 passed; 10 failed; 6 ignored; 0 measured; 0 filtered out; finished in 3.57s
error: test failed, to rerun pass `-p coretests --test coretests`
env -u RUSTC_WRAPPER CARGO_ENCODED_RUSTDOCFLAGS="-Csymbol-mangling-version=v0\u{1f}-Zannotate-moves\u{1f}-Zrandomize-layout\u{1f}-Zunstable-options\u{1f}--check-cfg=cfg(bootstrap)\u{1f}-Dwarnings\u{1f}-Wrustdoc::invalid_codeblock_attributes\u{1f}--crate-version\u{1f}1.93.0-nightly\t(1b0799f26\t2025-11-22)" CARGO_ENCODED_RUSTFLAGS="-Csymbol-mangling-version=v0\u{1f}-Zannotate-moves\u{1f}-Zrandomize-layout\u{1f}-Zunstable-options\u{1f}--check-cfg=cfg(bootstrap)\u{1f}-Zmacro-backtrace\u{1f}-Csplit-debuginfo=off\u{1f}-Clink-arg=-L/usr/lib/llvm-20/lib\u{1f}-Cllvm-args=-import-instr-limit=10\u{1f}-Clink-args=-Wl,-z,origin\u{1f}-Clink-args=-Wl,-rpath,$ORIGIN/../lib\u{1f}-Alinker-messages\u{1f}--cap-lints=allow\u{1f}--cfg\u{1f}randomized_layouts" RUSTC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustc-clif" RUSTDOC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustdoc-clif" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo" "test" "--manifest-path" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/sysroot_tests/Cargo.toml" "--target-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/sysroot_tests_target" "--locked" "--target" "aarch64-unknown-linux-gnu" "-p" "coretests" "-p" "alloctests" "--tests" "--" "-q" exited with status ExitStatus(unix_wait_status(25856))
Bootstrap failed while executing `--stage 2 test --skip tests --skip coverage-map --skip coverage-run --skip library --skip tidyselftest`
Command `/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo run --target aarch64-unknown-linux-gnu -Zbinary-dep-depinfo -j 4 -Zroot-dir=/checkout --locked --color always --release --manifest-path /checkout/compiler/rustc_codegen_cranelift/build_system/Cargo.toml -- test --download-dir /checkout/obj/build/cg_clif_download --out-dir /checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif --no-unstable-features --use-backend cranelift --sysroot llvm --skip-test testsuite.extended_sysroot [workdir=/checkout/compiler/rustc_codegen_cranelift]` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/test.rs:3723:25
Executed at: src/bootstrap/src/core/build_steps/test.rs:3768:26
Command has failed. Rerun with -v to see more details.
Build completed unsuccessfully in 0:21:42
local time: Sat Nov 22 03:50:37 UTC 2025
network time: Sat, 22 Nov 2025 03:50:38 GMT
##[error]Process completed with exit code 1.
##[group]Run echo "disk usage:"
The job aarch64-gnu-llvm-20-2 failed! Check out the build log: (web) (plain enhanced) (plain)
Click to see the possible cause of the failure (guessed by this bot)
num::u8::panicking_pow
test result: FAILED. 2253 passed; 5 failed; 6 ignored; 0 measured; 0 filtered out; finished in 2.99s
error: test failed, to rerun pass `-p coretests --test coretests`
env -u RUSTC_WRAPPER CARGO_ENCODED_RUSTDOCFLAGS="-Csymbol-mangling-version=v0\u{1f}-Zannotate-moves\u{1f}-Zrandomize-layout\u{1f}-Zunstable-options\u{1f}--check-cfg=cfg(bootstrap)\u{1f}-Dwarnings\u{1f}-Wrustdoc::invalid_codeblock_attributes\u{1f}--crate-version\u{1f}1.93.0-nightly\t(739c484aa\t2025-11-23)" CARGO_ENCODED_RUSTFLAGS="-Csymbol-mangling-version=v0\u{1f}-Zannotate-moves\u{1f}-Zrandomize-layout\u{1f}-Zunstable-options\u{1f}--check-cfg=cfg(bootstrap)\u{1f}-Zmacro-backtrace\u{1f}-Csplit-debuginfo=off\u{1f}-Clink-arg=-L/usr/lib/llvm-20/lib\u{1f}-Cllvm-args=-import-instr-limit=10\u{1f}-Clink-args=-Wl,-z,origin\u{1f}-Clink-args=-Wl,-rpath,$ORIGIN/../lib\u{1f}-Alinker-messages\u{1f}--cap-lints=allow\u{1f}--cfg\u{1f}randomized_layouts" RUSTC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustc-clif" RUSTDOC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/dist/rustdoc-clif" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo" "test" "--manifest-path" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/sysroot_tests/Cargo.toml" "--target-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif/build/sysroot_tests_target" "--locked" "--target" "aarch64-unknown-linux-gnu" "-p" "coretests" "-p" "alloctests" "--tests" "--" "-q" exited with status ExitStatus(unix_wait_status(25856))
Command `/checkout/obj/build/aarch64-unknown-linux-gnu/stage0/bin/cargo run --target aarch64-unknown-linux-gnu -Zbinary-dep-depinfo -j 4 -Zroot-dir=/checkout --locked --color always --release --manifest-path /checkout/compiler/rustc_codegen_cranelift/build_system/Cargo.toml -- test --download-dir /checkout/obj/build/cg_clif_download --out-dir /checkout/obj/build/aarch64-unknown-linux-gnu/stage2-codegen/cg_clif --no-unstable-features --use-backend cranelift --sysroot llvm --skip-test testsuite.extended_sysroot [workdir=/checkout/compiler/rustc_codegen_cranelift]` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/test.rs:3723:25
Executed at: src/bootstrap/src/core/build_steps/test.rs:3768:26
Command has failed. Rerun with -v to see more details.
Bootstrap failed while executing `--stage 2 test --skip tests --skip coverage-map --skip coverage-run --skip library --skip tidyselftest`
Build completed unsuccessfully in 0:22:50
local time: Sun Nov 23 18:01:23 UTC 2025
network time: Sun, 23 Nov 2025 18:01:23 GMT
##[error]Process completed with exit code 1.
This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.
Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.
The job aarch64-gnu-llvm-20-1 failed! Check out the build log: (web) (plain enhanced) (plain)
Click to see the possible cause of the failure (guessed by this bot)
failures:
---- [ui] tests/ui/numbers-arithmetic/overflowing-pow-unsigned.rs stdout ----
error: error pattern 'attempt to (multiply|shift left) with overflow' not found!
status: exit status: 101
command: cd "/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/numbers-arithmetic/overflowing-pow-unsigned" && RUSTC="/checkout/obj/build/aarch64-unknown-linux-gnu/stage2/bin/rustc" RUST_TEST_THREADS="4" "/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/numbers-arithmetic/overflowing-pow-unsigned/a"
stdout: none
--- stderr -------------------------------