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2025-06-03cg_clif: convert to CanonAbiJubilee Young-27/+22
2025-06-03Add impl for `llvm.roundeven` in cg_clifsayantn-9/+9
- remove unused `llvm.aarch64.neon.frintn` from cg_clif
2025-06-03Move metadata object generation for dylibs to the linker codebjorn3-48/+3
This deduplicates some code between codegen backends and may in the future allow adding extra metadata that is only known at link time.
2025-06-03Only borrow EncodedMetadata in codegen_cratebjorn3-18/+4
And move passing it to the linker to the driver code.
2025-05-28atomic_load intrinsic: use const generic parameter for orderingRalf Jung-1/+2
2025-05-28clif: Provide better output messages for failed copiesTrevor Gross-3/+5
2025-05-25Merge commit '979dcf8e2f213e4f4b645cb62e7fe9f4f2c0c785' into ↵bjorn3-265/+1110
sync_cg_clif-2025-05-25
2025-05-20Rename `cfg_match!` to `cfg_select!`Trevor Gross-1/+1
At [1] it was pointed out that `cfg_match!` syntax does not actually align well with match syntax, which is a possible source of confusion. The comment points out that usage is instead more similar to ecosystem `select!` macros. Rename `cfg_match!` to `cfg_select!` to match this. Tracking issue: https://github.com/rust-lang/rust/issues/115585 [1]: https://github.com/rust-lang/rust/issues/115585#issuecomment-2346307605
2025-05-09Use intrinsics for `{f16,f32,f64,f128}::{minimum,maximum}` operationsUrgau-0/+37
2025-05-05Rename Instance::new to Instance::new_raw and add a note that it is rawMichael Goulet-1/+1
2025-04-30Rollup merge of #134232 - bjorn3:naked_asm_improvements, r=wesleywiserMatthias Krüger-289/+200
Share the naked asm impl between cg_ssa and cg_clif This was introduced in https://github.com/rust-lang/rust/pull/128004.
2025-04-30Fix naked asm symbol name for cg_clif on macOSbjorn3-1/+2
2025-04-28Rollup merge of #140323 - tgross35:cfg-unstable-float, r=UrgauChris Denton-3/+12
Implement the internal feature `cfg_target_has_reliable_f16_f128` Support for `f16` and `f128` is varied across targets, backends, and backend versions. Eventually we would like to reach a point where all backends support these approximately equally, but until then we have to work around some of these nuances of support being observable. Introduce the `cfg_target_has_reliable_f16_f128` internal feature, which provides the following new configuration gates: * `cfg(target_has_reliable_f16)` * `cfg(target_has_reliable_f16_math)` * `cfg(target_has_reliable_f128)` * `cfg(target_has_reliable_f128_math)` `reliable_f16` and `reliable_f128` indicate that basic arithmetic for the type works correctly. The `_math` versions indicate that anything relying on `libm` works correctly, since sometimes this hits a separate class of codegen bugs. These options match configuration set by the build script at [1]. The logic for LLVM support is duplicated as-is from the same script. There are a few possible updates that will come as a follow up. The config introduced here is not planned to ever become stable, it is only intended to replace the build scripts for `std` tests and `compiler-builtins` that don't have any way to configure based on the codegen backend. MCP: https://github.com/rust-lang/compiler-team/issues/866 Closes: https://github.com/rust-lang/compiler-team/issues/866 [1]: https://github.com/rust-lang/rust/blob/555e1d0386f024a8359645c3217f4b3eae9be042/library/std/build.rs#L84-L186 --- The second commit makes use of this config to replace `cfg_{f16,f128}{,_math}` in `library/`. I omitted providing a `cfg(bootstrap)` configuration to keep things simpler since the next beta branch is in two weeks. try-job: aarch64-gnu try-job: i686-msvc-1 try-job: test-various try-job: x86_64-gnu try-job: x86_64-msvc-ext2
2025-04-28AsyncDrop implementation using shim codegen of ↵Andrew Zhogin-5/+10
async_drop_in_place::{closure}, scoped async drop added.
2025-04-27Implement the internal feature `cfg_target_has_reliable_f16_f128`Trevor Gross-3/+12
Support for `f16` and `f128` is varied across targets, backends, and backend versions. Eventually we would like to reach a point where all backends support these approximately equally, but until then we have to work around some of these nuances of support being observable. Introduce the `cfg_target_has_reliable_f16_f128` internal feature, which provides the following new configuration gates: * `cfg(target_has_reliable_f16)` * `cfg(target_has_reliable_f16_math)` * `cfg(target_has_reliable_f128)` * `cfg(target_has_reliable_f128_math)` `reliable_f16` and `reliable_f128` indicate that basic arithmetic for the type works correctly. The `_math` versions indicate that anything relying on `libm` works correctly, since sometimes this hits a separate class of codegen bugs. These options match configuration set by the build script at [1]. The logic for LLVM support is duplicated as-is from the same script. There are a few possible updates that will come as a follow up. The config introduced here is not planned to ever become stable, it is only intended to replace the build scripts for `std` tests and `compiler-builtins` that don't have any way to configure based on the codegen backend. MCP: https://github.com/rust-lang/compiler-team/issues/866 Closes: https://github.com/rust-lang/compiler-team/issues/866 [1]: https://github.com/rust-lang/rust/blob/555e1d0386f024a8359645c3217f4b3eae9be042/library/std/build.rs#L84-L186
2025-04-24Suggest {to,from}_ne_bytes for transmutations between arrays and integers, etcbendn-1/+1
2025-04-24Auto merge of #139309 - RalfJung:abi_unsupported_vector_types, ↵bors-3/+0
r=fee1-dead,traviscross make abi_unsupported_vector_types a hard error Fixes https://github.com/rust-lang/rust/issues/116558 by completing the transition; see that issue for context. The lint was introduced with Rust 1.84 and this has been shown in cargo's future breakage reports since Rust 1.85, released 6 weeks ago, and so far we got 0 complaints by users. There's not even a backlink on the tracking issue. We did a [crater run](https://github.com/rust-lang/rust/pull/127731#issuecomment-2286736295) when the lint was originally added and found no breakage. So I don't think we need another crater run now, but I can do one if the team prefers that. https://github.com/rust-lang/rust/issues/131800 is done, so for most current targets (in particular, all tier 1 and tier 2 targets) we have the information to implement this check (modulo the targets where we don't properly support SIMD vectors yet, see the sub-issues of https://github.com/rust-lang/rust/issues/116558). If a new target gets added in the future, it will default to reject all SIMD vector types until proper information is added, which is the default we want. This will need approval by for `@rust-lang/lang.` Cc `@workingjubilee` `@veluca93` try-job: test-various try-job: armhf-gnu try-job: dist-i586-gnu-i586-i686-musl
2025-04-20make abi_unsupported_vector_types a hard errorRalf Jung-3/+0
2025-04-20stabilize `naked_functions`Folkert de Vries-10/+1
2025-04-19Make `#[naked]` an unsafe attributeFolkert de Vries-4/+2
2025-04-14Share part of the global_asm!() implementation between cg_ssa and cg_clifbjorn3-69/+4
2025-04-14Use cg_ssa's version of codegen_naked_asm in cg_clifbjorn3-283/+258
2025-04-14Move `has_self` field to `hir::AssocKind::Fn`.Nicholas Nethercote-2/+2
`hir::AssocItem` currently has a boolean `fn_has_self_parameter` field, which is misplaced, because it's only relevant for associated fns, not for associated consts or types. This commit moves it (and renames it) to the `AssocKind::Fn` variant, where it belongs. This requires introducing a new C-style enum, `AssocTag`, which is like `AssocKind` but without the fields. This is because `AssocKind` values are passed to various functions like `find_by_ident_and_kind` to indicate what kind of associated item should be searched for, and having to specify `has_self` isn't relevant there. New methods: - Predicates `AssocItem::is_fn` and `AssocItem::is_method`. - `AssocItem::as_tag` which converts `AssocItem::kind` to `AssocTag`. Removed `find_by_name_and_kinds`, which is unused. `AssocItem::descr` can now distinguish between methods and associated functions, which slightly improves some error messages.
2025-04-11Auto merge of #139453 - compiler-errors:incr, r=jieyouxubors-19/+35
Prepend temp files with per-invocation random string to avoid temp filename conflicts https://github.com/rust-lang/rust/issues/139407 uncovered a very subtle unsoundness with incremental codegen, failing compilation sessions (due to assembler errors), and the "prefer hard linking over copying files" strategy we use in the compiler for file management. Specifically, imagine we're building a single file 3 times, all with `-Csave-temps -Cincremental=...`. Let's call the object file we're building for the codegen unit for `main` "`XXX.o`" just for clarity since it's probably some gigantic hash name: ``` #[inline(never)] #[cfg(any(rpass1, rpass3))] fn a() -> i32 { 0 } #[cfg(any(cfail2))] fn a() -> i32 { 1 } fn main() { evil::evil(); assert_eq!(a(), 0); } mod evil { #[cfg(any(rpass1, rpass3))] pub fn evil() { unsafe { std::arch::asm!("/* */"); } } #[cfg(any(cfail2))] pub fn evil() { unsafe { std::arch::asm!("missing"); } } } ``` Session 1 (`rpass1`): * Type-check, borrow-check, etc. * Serialize the dep graph to the incremental working directory `.../s-...-working/`. * Codegen object file to a temp file `XXX.rcgu.o` which is spit out in the cwd. * Hard-link[^1] `XXX.rcgu.o` to the incremental working directory `.../s-...-working/XXX.o`. * Save-temps option means we don't delete `XXX.rgcu.o`. * Link the binary and stuff. * Finalize[^2] the working incremental session by renaming `.../s-...-working` to ` s-...-asjkdhsjakd` (some other finalized incr comp session dir name). Session 2 (`cfail2`): * Load artifacts from the previous *finalized* incremental session, namely the dep graph. * Type-check, borrow-check, etc. since the file has changed, so most dep graph nodes are red. * Serialize the dep graph to the incremental working directory `.../s-...-working/`. * Codegen object file to a temp file `XXX.rcgu.o`. **HERE IS THE PROBLEM**: The hard-link is still set up to point to the inode from `XXX.o` from the first session, so this also modifies the `XXX.o` in the previous finalized session directory. * Codegen emits an error b/c `missing` is not an instruction, so we abort before finalizing the incremental session. Specifically, this means that the *previous* session is the last finalized session. Session 3 (`rpass3`): * Load artifacts from the previous *finalized* incremental session, namely the dep graph. NOTE that this is from session 1. * All the dep graph nodes are green since we are basically replaying session 1. * codegen object file `XXX.o`, which is detected as *reused* from session 1 since dep nodes were green. That means we **reuse** `XXX.o` which had been dirtied from session 2. * Link the binary and stuff. This results in a binary which reuses some of the build artifacts from session 2, but thinks it's from session 1. At this point, I hope it's clear to see that the incremental results from session 1 were dirtied from session 2, but we reuse them as if session 1 was the previous (finalized) incremental session we ran. This is at best really buggy, and at worst **unsound**. This isn't limited to `-C save-temps`, since there are other combinations of flags that may keep around temporary files (hard linked) in the working directory (like `-C debuginfo=1 -C split-debuginfo=unpacked` on darwin, for example). --- This PR implements a fix which is to prepend temp filenames with a random string that is generated per invocation of rustc. This string is not *deterministic*, but temporary files are transient anyways, so I don't believe this is a problem. That means that temp files are now something like... `{crate-name}.{cgu}.{invocation_temp}.rcgu.o`, where `{invocation_temp}` is the new temporary string we generate per invocation of rustc. Fixes https://github.com/rust-lang/rust/issues/139407 [^1]: https://github.com/rust-lang/rust/blob/175dcc7773d65c1b1542c351392080f48c05799f/compiler/rustc_fs_util/src/lib.rs#L60 [^2]: https://github.com/rust-lang/rust/blob/175dcc7773d65c1b1542c351392080f48c05799f/compiler/rustc_incremental/src/persist/fs.rs#L1-L40
2025-04-11Auto merge of #139011 - Zoxc:no-rayon-iters, r=oli-obkbors-14/+15
Remove the use of Rayon iterators This removes the use of Rayon iterators and the use of the `rustc-rayon` crate. `rustc-rayon-core` is still used however. In parallel loops, instead of a Rayon iterator a serial iterator are used to collect items into a `Vec` and we use a parallel loop over its elements using the new `par_slice` function which is built on `rustc-rayon-core`'s `join`. This change makes it easier to bring `rustc-rayon-core` in-tree. Tests using 7 threads: <table><tr><td rowspan="2">Benchmark</td><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th></tr><tr><td align="right">Time</td><td align="right">Time</td><td align="right">%</th><td align="right">Physical Memory</td><td align="right">Physical Memory</td><td align="right">%</th><td align="right">Committed Memory</td><td align="right">Committed Memory</td><td align="right">%</th></tr><tr><td>🟣 <b>clap</b>:check</td><td align="right">0.4827s</td><td align="right">0.4828s</td><td align="right"> 0.02%</td><td align="right">201.23 MiB</td><td align="right">201.31 MiB</td><td align="right"> 0.04%</td><td align="right">279.03 MiB</td><td align="right">279.46 MiB</td><td align="right"> 0.15%</td></tr><tr><td>🟣 <b>hyper</b>:check</td><td align="right">0.1443s</td><td align="right">0.1401s</td><td align="right">💚 -2.91%</td><td align="right">126.42 MiB</td><td align="right">126.70 MiB</td><td align="right"> 0.22%</td><td align="right">199.79 MiB</td><td align="right">199.99 MiB</td><td align="right"> 0.10%</td></tr><tr><td>🟣 <b>regex</b>:check</td><td align="right">0.3252s</td><td align="right">0.3065s</td><td align="right">💚 -5.78%</td><td align="right">161.87 MiB</td><td align="right">161.78 MiB</td><td align="right"> -0.05%</td><td align="right">229.59 MiB</td><td align="right">230.23 MiB</td><td align="right"> 0.28%</td></tr><tr><td>🟣 <b>syn</b>:check</td><td align="right">0.5845s</td><td align="right">0.5876s</td><td align="right"> 0.53%</td><td align="right">197.01 MiB</td><td align="right">196.89 MiB</td><td align="right"> -0.06%</td><td align="right">267.62 MiB</td><td align="right">267.47 MiB</td><td align="right"> -0.06%</td></tr><tr><td>Total</td><td align="right">1.5367s</td><td align="right">1.5169s</td><td align="right">💚 -1.29%</td><td align="right">686.53 MiB</td><td align="right">686.68 MiB</td><td align="right"> 0.02%</td><td align="right">976.04 MiB</td><td align="right">977.14 MiB</td><td align="right"> 0.11%</td></tr><tr><td>Summary</td><td align="right">1.0000s</td><td align="right">0.9796s</td><td align="right">💚 -2.04%</td><td align="right">1 byte</td><td align="right">1.00 bytes</td><td align="right"> 0.04%</td><td align="right">1 byte</td><td align="right">1.00 bytes</td><td align="right"> 0.12%</td></tr></table> <table><tr><td rowspan="2">Benchmark</td><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th></tr><tr><td align="right">Time</td><td align="right">Time</td><td align="right">%</th><td align="right">Physical Memory</td><td align="right">Physical Memory</td><td align="right">%</th><td align="right">Committed Memory</td><td align="right">Committed Memory</td><td align="right">%</th></tr><tr><td>🟠 <b>clap</b>:debug</td><td align="right">1.6371s</td><td align="right">1.6529s</td><td align="right"> 0.96%</td><td align="right">395.58 MiB</td><td align="right">396.21 MiB</td><td align="right"> 0.16%</td><td align="right">460.98 MiB</td><td align="right">461.52 MiB</td><td align="right"> 0.12%</td></tr><tr><td>🟠 <b>hyper</b>:debug</td><td align="right">0.3248s</td><td align="right">0.3210s</td><td align="right">💚 -1.16%</td><td align="right">155.16 MiB</td><td align="right">155.19 MiB</td><td align="right"> 0.02%</td><td align="right">219.21 MiB</td><td align="right">219.30 MiB</td><td align="right"> 0.04%</td></tr><tr><td>🟠 <b>regex</b>:debug</td><td align="right">1.0148s</td><td align="right">0.9929s</td><td align="right">💚 -2.16%</td><td align="right">297.96 MiB</td><td align="right">295.07 MiB</td><td align="right"> -0.97%</td><td align="right">354.53 MiB</td><td align="right">351.58 MiB</td><td align="right"> -0.83%</td></tr><tr><td>🟠 <b>syn</b>:debug</td><td align="right">1.3614s</td><td align="right">1.3717s</td><td align="right"> 0.76%</td><td align="right">319.10 MiB</td><td align="right">321.19 MiB</td><td align="right"> 0.65%</td><td align="right">378.90 MiB</td><td align="right">381.27 MiB</td><td align="right"> 0.62%</td></tr><tr><td>Total</td><td align="right">4.3381s</td><td align="right">4.3386s</td><td align="right"> 0.01%</td><td align="right">1.14 GiB</td><td align="right">1.14 GiB</td><td align="right"> -0.01%</td><td align="right">1.38 GiB</td><td align="right">1.38 GiB</td><td align="right"> 0.00%</td></tr><tr><td>Summary</td><td align="right">1.0000s</td><td align="right">0.9960s</td><td align="right"> -0.40%</td><td align="right">1 byte</td><td align="right">1.00 bytes</td><td align="right"> -0.03%</td><td align="right">1 byte</td><td align="right">1.00 bytes</td><td align="right"> -0.01%</td></tr></table>
2025-04-10Remove the use of Rayon iteratorsJohn Kåre Alsaker-14/+15
2025-04-10Rename some `name` variables as `ident`.Nicholas Nethercote-1/+1
It bugs me when variables of type `Ident` are called `name`. It leads to silly things like `name.name`. `Ident` variables should be called `ident`, and `name` should be used for variables of type `Symbol`. This commit improves things by by doing `s/name/ident/` on a bunch of `Ident` variables. Not all of them, but a decent chunk.
2025-04-07Prepend temp files with a string per invocation of rustcMichael Goulet-9/+31
2025-04-07Simplify temp path creation a bitMichael Goulet-16/+10
2025-04-06update docsBennet Bleßmann-2/+1
- src\doc\nomicon\src\ffi.md should also have its ABI list updated
2025-04-04Auto merge of #139213 - bjorn3:cg_clif_test_coretests, r=jieyouxubors-23/+34
Run coretests and alloctests with cg_clif in CI Part of https://github.com/rust-lang/rustc_codegen_cranelift/issues/1290
2025-04-04Rollup merge of #138949 - madsmtm:rename-to-darwin, r=WaffleLapkinMatthias Krüger-3/+3
Rename `is_like_osx` to `is_like_darwin` Replace `is_like_osx` with `is_like_darwin`, which more closely describes reality (OS X is the pre-2016 name for macOS, and is by now quite outdated; Darwin is the overall name for the OS underlying Apple's macOS, iOS, etc.). ``@rustbot`` label O-apple r? compiler
2025-04-03Fix testing with randomized layouts enabledbjorn3-1/+3
2025-04-03Run coretests and alloctests with cg_clif in CIbjorn3-22/+27
2025-04-03Unset RUSTC_WRAPPER in cg_clif's build systembjorn3-1/+5
2025-04-01Allow formatting example/gen_block_iterate.rsbjorn3-8/+12
2025-03-30Merge commit 'ba315abda789c9f59f2100102232bddb30b0d3d3' into ↵bjorn3-1419/+533
sync_cg_clif-2025-03-30
2025-03-25Rename `is_like_osx` to `is_like_darwin`Mads Marquart-3/+3
2025-03-24Update `compiler-builtins` to 0.1.152Trevor Gross-2/+2
Includes the following changes related to unordered atomics: * Remove element_unordered_atomic intrinsics [1] * Remove use of `atomic_load_unordered` and undefined behaviour [2] There are a handful of other small changes, but nothing else user-visible. [1]: https://github.com/rust-lang/compiler-builtins/pull/789 [2]: https://github.com/rust-lang/compiler-builtins/pull/790
2025-03-21Auto merge of #128320 - saethlin:link-me-maybe, r=compiler-errorsbors-6/+14
Avoid no-op unlink+link dances in incr comp Incremental compilation scales quite poorly with the number of CGUs. This PR improves one reason for that. The incr comp process hard-links all the files from an old session into a new one, then it runs the backend, which may just hard-link the new session files into the output directory. Then codegen hard-links all the output files back to the new session directory. This PR (perhaps unimaginatively) fixes the silliness that ensues in the last step. The old `link_or_copy` implementation would be passed pairs of paths which are already the same inode, then it would blindly delete the destination and re-create the hard-link that it just deleted. This PR lets us skip both those operations. We don't skip the other two hard-links. `cargo +stage1 b && touch crates/core/main.rs && strace -cfw -elink,linkat,unlink,unlinkat cargo +stage1 b` before and then after on `ripgrep-13.0.0`: ``` % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 52.56 0.024950 25 978 485 unlink 34.38 0.016318 22 727 linkat 13.06 0.006200 24 249 unlinkat ------ ----------- ----------- --------- --------- ---------------- 100.00 0.047467 24 1954 485 total ``` ``` % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 42.83 0.014521 57 252 unlink 38.41 0.013021 26 486 linkat 18.77 0.006362 25 249 unlinkat ------ ----------- ----------- --------- --------- ---------------- 100.00 0.033904 34 987 total ``` This reduces the number of hard-links that are causing perf troubles, noted in https://github.com/rust-lang/rust/issues/64291 and https://github.com/rust-lang/rust/issues/137560
2025-03-17Remove implicit #[no_mangle] for #[rustc_std_internal_symbol]bjorn3-7/+24
2025-03-16Rollup merge of #138082 - thaliaarchi:slice-cfg-not-test, r=thomcc许杰友 Jieyou Xu (Joe)-13/+11
Remove `#[cfg(not(test))]` gates in `core` These gates are unnecessary now that unit tests for `core` are in a separate package, `coretests`, instead of in the same files as the source code. They previously prevented the two `core` versions from conflicting with each other.
2025-03-13atomic intrinsics: clarify which types are supported and (if applicable) ↵Ralf Jung-4/+4
what happens with provenance
2025-03-12intrinsics: remove unnecessary leading underscore from argument namesRalf Jung-8/+8
2025-03-11Auto merge of #128440 - oli-obk:defines, r=lcnrbors-13/+11
Add `#[define_opaques]` attribute and require it for all type-alias-impl-trait sites that register a hidden type Instead of relying on the signature of items to decide whether they are constraining an opaque type, the opaque types that the item constrains must be explicitly listed. A previous version of this PR used an actual attribute, but had to keep the resolved `DefId`s in a side table. Now we just lower to fields in the AST that have no surface syntax, instead a builtin attribute macro fills in those fields where applicable. Note that for convenience referencing opaque types in associated types from associated methods on the same impl will not require an attribute. If that causes problems `#[defines()]` can be used to overwrite the default of searching for opaques in the signature. One wart of this design is that closures and static items do not have generics. So since I stored the opaques in the generics of functions, consts and methods, I would need to add a custom field to closures and statics to track this information. During a T-types discussion we decided to just not do this for now. fixes #131298
2025-03-11Auto merge of #137586 - nnethercote:SetImpliedBits, r=bjorn3bors-7/+6
Speed up target feature computation The LLVM backend calls `LLVMRustHasFeature` twice for every feature. In short-running rustc invocations, this accounts for a surprising amount of work. r? `@bjorn3`
2025-03-11Implement `#[define_opaque]` attribute for functions.Oli Scherer-13/+11
2025-03-07Fully test the alloc crate through alloctestsbjorn3-3/+3
For the tests that make use of internal implementation details, we include the module to test using #[path] in alloctests now.
2025-03-06Remove #[cfg(not(test))] gates in coreThalia Archibald-13/+11
These gates are unnecessary now that unit tests for `core` are in a separate package, `coretests`, instead of in the same files as the source code. They previously prevented the two `core` versions from conflicting with each other.
2025-03-05Update `compiler-builtins` to 0.1.151Trevor Gross-2/+2
This enables `f16` builtins for loongarch [1] and adds support for Cygwin [2]. [1]: https://github.com/rust-lang/compiler-builtins/pull/770 [2]: https://github.com/rust-lang/compiler-builtins/pull/774