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2025-08-18Auto merge of #145551 - Zalathar:rollup-eo75r94, r=Zalatharbors-257/+1150
Rollup of 10 pull requests Successful merges: - rust-lang/rust#144838 (Fix outdated doc comment) - rust-lang/rust#145206 (Port `#[custom_mir(..)]` to the new attribute system) - rust-lang/rust#145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - rust-lang/rust#145309 (Fix `-Zregparm` for LLVM builtins) - rust-lang/rust#145355 (Add codegen test for issue 122734) - rust-lang/rust#145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - rust-lang/rust#145451 (Add static glibc to the nix dev shell) - rust-lang/rust#145460 (Speedup `copy_src_dirs` in bootstrap) - rust-lang/rust#145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - rust-lang/rust#145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
2025-08-18Rollup merge of #145485 - JonathanBrouwer:fix-deprecation-targets, ↵Stuart Cook-3/+13
r=jdonszelmann Fix deprecation attributes on foreign statics r? ````````@jdonszelmann```````` Fixes https://github.com/rust-lang/rust/issues/145437
2025-08-18Rollup merge of #145476 - alurm:patch-1, r=ibraheemdevStuart Cook-1/+1
Fix typo in doc for library/std/src/fs.rs#set_permissions "privalage" -> "privilege". Was reading the docs and have noticed this.
2025-08-18Rollup merge of #145460 - Kobzol:bootstrap-speedup-copy-src-dirs, r=jieyouxuStuart Cook-40/+42
Speedup `copy_src_dirs` in bootstrap I was kinda offended by how slow it was. Just the `copy_src_dirs` part took ~3s locally in the `x dist rustc-src` step. In release mode it was just 1s, but that's kind of cheating (I wonder if we should build bootstrap in release mode on CI though...). Did some basic optimizations to bring it down to ~1s also in debug mode. Maybe it's overkill, due to https://github.com/rust-lang/rust/pull/145455. Up to you whether we should merge it or close it :) r? `````````@jieyouxu`````````
2025-08-18Rollup merge of #145451 - WaffleLapkin:norailoveyou, r=NoratriebStuart Cook-0/+1
Add static glibc to the nix dev shell This fixes `tests/ui/process/nofile-limit.rs` which fails to link on nixos for me without this change.
2025-08-18Rollup merge of #145420 - Zalathar:llvm-c, r=WaffleLapkinStuart Cook-89/+14
cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind` This PR replaces two existing `LLVMRust` bindings with equivalent calls to the LLVM-C API. For `LLVMGetTypeKind`, we avoid the UB hazard by declaring the foreign function to return `RawEnum<TypeKind>` (which is a wrapper around `u32`), and then perform checked conversion from `u32` to `TypeKind`.
2025-08-18Rollup merge of #145355 - clubby789:option-match-eq, r=nikicStuart Cook-0/+78
Add codegen test for issue 122734 Closes rust-lang/rust#122734
2025-08-18Rollup merge of #145309 - winstonallo:issue-145271-fix, r=tgross35Stuart Cook-0/+86
Fix `-Zregparm` for LLVM builtins This fixes the issue where `-Zregparm=N` was not working correctly when calling LLVM intrinsics By default on `x86-32`, arguments are passed on the stack. The `-Zregparm=N` flag allows the first `N` arguments to be passed in registers instead. When calling intrinsics like `memset`, LLVM still passes parameters on the stack, which prevents optimizations like tail calls. As proposed by ````@tgross35,```` I fixed this by setting the `NumRegisterParameters` LLVM module flag to `N` when the `-Zregparm=N` is set. ```rust // compiler/rust_codegen_llvm/src/context.rs#375-382 if let Some(regparm_count) = sess.opts.unstable_opts.regparm { llvm::add_module_flag_u32( llmod, llvm::ModuleFlagMergeBehavior::Error, "NumRegisterParameters", regparm_count, ); } ``` [Here](https://rust.godbolt.org/z/YMezreo48) is a before/after compiler explorer. Here is the final result for the code snippet in the original issue: ```asm entrypoint: push esi mov esi, eax mov eax, ecx mov ecx, esi pop esi jmp memset ; Tail call parameters in registers ``` Fixes: https://github.com/rust-lang/rust/issues/145271
2025-08-18Rollup merge of #145208 - joshtriplett:mbe-derive, r=petrochenkovStuart Cook-29/+593
Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop https://github.com/rust-lang/rust/pull/145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: https://github.com/rust-lang/rust/issues/143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
2025-08-18Rollup merge of #145206 - scrabsha:push-uxovoqzrxnlx, r=jdonszelmannStuart Cook-91/+318
Port `#[custom_mir(..)]` to the new attribute system r? ``````````@jdonszelmann``````````
2025-08-18Rollup merge of #144838 - Kivooeo:doc-subtype, r=notriddleStuart Cook-4/+4
Fix outdated doc comment This updates the documentation comment for `Type::is_doc_subtype_of` to more accurately describe its purpose as a subtyping check, rather than equality fixes rust-lang/rust#138572 r? ````````````@tgross35````````````
2025-08-17Auto merge of #145284 - nnethercote:type_name-print-regions, r=lcnrbors-57/+78
Print regions in `type_name`. Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`. Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo. `c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter. The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions. Fixes rust-lang/rust#145168. r? `@lcnr`
2025-08-17Auto merge of #144081 - RalfJung:const-ptr-fragments, r=oli-obkbors-358/+542
const-eval: full support for pointer fragments This fixes https://github.com/rust-lang/const-eval/issues/72 and makes `swap_nonoverlapping` fully work in const-eval by enhancing per-byte provenance tracking with tracking of *which* of the bytes of the pointer this one is. Later, if we see all the same bytes in the exact same order, we can treat it like a whole pointer again without ever risking a leak of the data bytes (that encode the offset into the allocation). This lifts the limitation that was discussed quite a bit in https://github.com/rust-lang/rust/pull/137280. For a concrete piece of code that used to fail and now works properly consider this example doing a byte-for-byte memcpy in const without using intrinsics: ```rust use std::{mem::{self, MaybeUninit}, ptr}; type Byte = MaybeUninit<u8>; const unsafe fn memcpy(dst: *mut Byte, src: *const Byte, n: usize) { let mut i = 0; while i < n { *dst.add(i) = *src.add(i); i += 1; } } const _MEMCPY: () = unsafe { let ptr = &42; let mut ptr2 = ptr::null::<i32>(); // Copy from ptr to ptr2. memcpy(&mut ptr2 as *mut _ as *mut _, &ptr as *const _ as *const _, mem::size_of::<&i32>()); assert!(*ptr2 == 42); }; ``` What makes this code tricky is that pointers are "opaque blobs" in const-eval, we cannot just let people look at the individual bytes since *we don't know what those bytes look like* -- that depends on the absolute address the pointed-to object will be placed at. The code above "breaks apart" a pointer into individual bytes, and then puts them back together in the same order elsewhere. This PR implements the logic to properly track how those individual bytes relate to the original pointer, and to recognize when they are in the right order again. We still reject constants where the final value contains a not-fully-put-together pointer: I have no idea how one could construct an LLVM global where one byte is defined as "the 3rd byte of a pointer to that other global over there" -- and even if LLVM supports this somehow, we can leave implementing that to a future PR. It seems unlikely to me anyone would even want this, but who knows.^^ This also changes the behavior of Miri, by tracking the order of bytes with provenance and only considering a pointer to have valid provenance if all bytes are in the original order again. This is related to https://github.com/rust-lang/unsafe-code-guidelines/issues/558. It means one cannot implement XOR linked lists with strict provenance any more, which is however only of theoretical interest. Practically I am curious if anyone will show up with any code that Miri now complains about - that would be interesting data. Cc `@rust-lang/opsem`
2025-08-16Auto merge of #145304 - m-ou-se:simplify-panic, r=oli-obkbors-73/+8
Revert "Partially outline code inside the panic! macro". This reverts https://github.com/rust-lang/rust/pull/115670 Without any tests/benchmarks that show some improvement, it's hard to know whether the change had any positive effect. (And if it did, whether that effect is still achieved today.)
2025-08-16Fix deprecation attribute on foreign statics & typesJonathan Brouwer-3/+10
2025-08-16Don't show foreign types as an allowed target if the feature is not enabledJonathan Brouwer-0/+3
2025-08-16Optimize `copy_src_dirs`Jakub Beránek-39/+42
2025-08-16Do not call `fs::remove_file` in `cp_link_filtered_recurse`Jakub Beránek-1/+0
The target is removed by `copy_link` too, so no need to duplicate the syscall.
2025-08-15Auto merge of #145475 - jhpratt:rollup-jr0wado, r=jhprattbors-36/+722
Rollup of 11 pull requests Successful merges: - rust-lang/rust#143717 (Add `Default` impls for `Pin`ned `Box`, `Rc`, `Arc`) - rust-lang/rust#144054 (Stabilize as_array_of_cells) - rust-lang/rust#144907 (fix: Reject async assoc fns of const traits/impls in ast_passes) - rust-lang/rust#144922 (Implement `#[derive(From)]`) - rust-lang/rust#144963 (Stabilize `core::iter::chain`) - rust-lang/rust#145436 (fix(tests/rmake/wasm-unexpected-features): change features from `WASM1` to `MVP`) - rust-lang/rust#145453 (Remove duplicated tracing span in bootstrap) - rust-lang/rust#145454 (Fix tracing debug representation of steps without arguments in bootstrap) - rust-lang/rust#145455 (Do not copy files in `copy_src_dirs` in dry run) - rust-lang/rust#145462 (Stabilize `const_exposed_provenance` feature) - rust-lang/rust#145466 (Enable new `[range-diff]` feature in triagebot) r? `@ghost` `@rustbot` modify labels: rollup
2025-08-16Fix typo in doc for library/std/src/fs.rs#set_permissionsAlan Urmancheev-1/+1
"privalage" -> "privilege"
2025-08-15Rollup merge of #145466 - Urgau:triagebot-range-diff, r=KobzolJacob Pratt-0/+5
Enable new `[range-diff]` feature in triagebot This new feature adds a comment to triagebot range-diff feature when a PR is rebased onto a different base/master commit. Related to [#t-compiler > Experimental range-diff for force-push @ 💬](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Experimental.20range-diff.20for.20force-push/near/534649322) r? Kobzol
2025-08-15Rollup merge of #145462 - Kivooeo:stabilize-const_exposed_provenance, r=RalfJungJacob Pratt-2/+2
Stabilize `const_exposed_provenance` feature This closes [tracking issue](https://github.com/rust-lang/rust/issues/144538) and stabilises `fn with_exposed_provenance` and `fn with_exposed_provenance_mut` in const
2025-08-15Rollup merge of #145455 - Kobzol:bootstrap-copy-src-dirs-dry-run, r=jieyouxuJacob Pratt-0/+6
Do not copy files in `copy_src_dirs` in dry run This reduces the time to run the current 9 dist snapshot tests from ~24s to ~2s on my PC. r? `@jieyouxu`
2025-08-15Rollup merge of #145454 - Kobzol:bootstrap-fix-step-debug-repr, r=jieyouxuJacob Pratt-3/+8
Fix tracing debug representation of steps without arguments in bootstrap I was wondering why I see `lainSourceTarbal` in tracing logs... r? `@jieyouxu`
2025-08-15Rollup merge of #145453 - Kobzol:bootstrap-cmd-span, r=jieyouxuJacob Pratt-3/+0
Remove duplicated tracing span in bootstrap `trace_cmd` is now called also in the `stream` method, so including it also here was duplicating command spans. r? `@jieyouxu`
2025-08-15Rollup merge of #145436 - StackOverflowExcept1on:patch-1, r=alexcrichtonJacob Pratt-1/+1
fix(tests/rmake/wasm-unexpected-features): change features from `WASM1` to `MVP` missed this in rust-lang/rust#145275 since test calls `rustc` with `-C target-cpu mvp` try-job: `test-various`
2025-08-15Rollup merge of #144963 - rossmacarthur-forks:stabilize-core-iter-chain, ↵Jacob Pratt-6/+3
r=jhpratt Stabilize `core::iter::chain` Closes rust-lang/rust#125964
2025-08-15Rollup merge of #144922 - Kobzol:derive-from, r=nnethercoteJacob Pratt-3/+582
Implement `#[derive(From)]` Implements the `#[derive(From)]` feature ([tracking issue](https://github.com/rust-lang/rust/issues/144889), [RFC](https://github.com/rust-lang/rfcs/pull/3809)). It allows deriving the `From` impl on structs and tuple structs with exactly one field. Some implementation notes: - I wasn't exactly sure which spans to use in the derive generating code, so I just used `span` everywhere. I don't know if it's the Right Thing To Do. In particular the errors when `#[derive(From)]` is used on a struct with an unsized field are weirdly duplicated. - I had to solve an import stability problem, where if I just added the unstable `macro From` to `core::convert`, previously working code like `use std::convert::From` would suddenly require an unstable feature gate, because rustc would think that you're trying to import the unstable macro. `@petrochenkov` suggested that I add the macro the the core prelude instead. This has worked well, although it only works in edition 2021+. Not sure if I botched the prelude somehow and it should live elsewhere (?). - I had to add `Ty::AstTy`, because the `from` function receives an argument with the type of the single field, and the existing variants of the `Ty` enum couldn't represent an arbitrary type.
2025-08-15Rollup merge of #144907 - ShoyuVanilla:no-const-async, r=fmeaseJacob Pratt-10/+69
fix: Reject async assoc fns of const traits/impls in ast_passes Fixes rust-lang/rust#117629
2025-08-15Rollup merge of #144054 - jsimmons:stabilize-as-array-of-cells, r=tgross35Jacob Pratt-4/+2
Stabilize as_array_of_cells This PR stabilizes ```rust impl<T, const N: usize> Cell<[T; N]> { pub const fn as_array_of_cells(&self) -> &[Cell<T>; N]; } ``` Stabilization report: https://github.com/rust-lang/rust/issues/88248#issuecomment-3082986863 Closes: https://github.com/rust-lang/rust/issues/88248
2025-08-15Rollup merge of #143717 - Jules-Bertholet:pin-default, r=dtolnayJacob Pratt-4/+44
Add `Default` impls for `Pin`ned `Box`, `Rc`, `Arc` Fixes rust-lang/rust#143688. `@rustbot` label T-libs-api needs-fcp Also needs a crater run, as the `Box` impls could theoretically be breaking due to `#[fundamental]` (though a [cursory search](https://github.com/search?q=%2Fimpl%28%3C.*%3E%29%3F+Default+for+Pin%3C%2F+path%3A*.rs&type=code) suggests this is unlikely to cause issues).
2025-08-15Auto merge of #142071 - lcnr:revealing-use, r=compiler-errorsbors-1/+72
`apply_member_constraints`: fix placeholder check Checking whether the member region is *an existential region from a higher universe* is just wrong and I am pretty sure we've added that check by accident as the naming was just horribly confusing before rust-lang/rust#140466. I've encountered this issue separately while working on rust-lang/rust#139587, but feel like it's probably easier to separately FCP this change. This allows the following code to compile ```rust trait Proj<'a> { type Assoc; } impl<'a, 'b, F: FnOnce() -> &'b ()> Proj<'a> for F { type Assoc = (); } fn is_proj<F: for<'a> Proj<'a>>(f: F) {} fn define<'a>() -> impl Sized + use<'a> { // This adds a use of `opaque::<'a>` with hidden type `&'unconstrained_b ()`. // 'unconstrained_b is an inference variable from a higher universe as it gets // created inside of the binder of `F: for<'a> Proj<'a>`. This previously // caused us to not apply member constraints. We now do, constraining // it to `'a`. is_proj(define::<'a>); &() } fn main() {} ``` This should not be breaking change, even in theory. Applying member constraints is incomplete in rare circumstances which means that applying them in more cases can cause spurious errors, cc rust-lang/rust#140569/rust-lang/rust#142073. However, as we always skipped these member regions in `apply_member_constraints` the skipped region is guaranteed to cause an error in `check_member_constraints` later on.
2025-08-15Enable new `[range-diff]` feature in triagebotUrgau-0/+5
2025-08-15stabilize const exposed provenanceKivooeo-2/+2
2025-08-15Auto merge of #145450 - Kobzol:rollup-cqclix0, r=Kobzolbors-339/+478
Rollup of 11 pull requests Successful merges: - rust-lang/rust#144210 (std: thread: Return error if setting thread stack size fails) - rust-lang/rust#145310 (Reduce usage of `compiler_for` in bootstrap) - rust-lang/rust#145311 (ci: clean windows disk space in background) - rust-lang/rust#145340 (Split codegen backend check step into two and don't run it with `x check compiler`) - rust-lang/rust#145408 (Deduplicate -L search paths) - rust-lang/rust#145412 (Windows: Replace `GetThreadId`+`GetCurrentThread` with `GetCurrentThreadId`) - rust-lang/rust#145413 (bootstrap: Reduce dependencies) - rust-lang/rust#145426 (Fix typos in bootstrap.example.toml) - rust-lang/rust#145430 (Fix wrong spans with external macros in the `dropping_copy_types` lint) - rust-lang/rust#145431 (Enhance UI test output handling for runtime errors) - rust-lang/rust#145448 (Autolabel `src/tools/{rustfmt,rust-analyzer}` changes with `T-{rustfmt,rust-analyzer}`) r? `@ghost` `@rustbot` modify labels: rollup
2025-08-15Do not copy files in `copy_src_dirs` in dry runJakub Beránek-0/+6
2025-08-15Fix tracing debug representation of steps without arguments in bootstrapJakub Beránek-3/+8
2025-08-15Remove duplicated tracing span in bootstrapJakub Beránek-3/+0
2025-08-15add static glibc to the nix dev shellWaffle Lapkin-0/+1
this fixes `tests/ui/process/nofile-limit.rs` which fails to link on nixos for me without this change
2025-08-15Rollup merge of #145448 - jieyouxu:rustfmt-labels, r=fmeaseJakub Beránek-0/+10
Autolabel `src/tools/{rustfmt,rust-analyzer}` changes with `T-{rustfmt,rust-analyzer}` Make e.g. rust-lang/rust#144323 more obvious who should be reviewing it and easier to filter.
2025-08-15Rollup merge of #145431 - AMS21:fix_141531, r=jieyouxuJakub Beránek-3/+15
Enhance UI test output handling for runtime errors When a UI test runs a compiled binary and an error/forbid pattern check fails, the failure message previously only showed compiler output, hiding the executed programs stdout/stderr. This makes it harder to see near-miss or unexpected runtime lines. Fixed rust-lang/rust#141531 Supersedes rust-lang/rust#141977
2025-08-15Rollup merge of #145430 - Urgau:drop_forget_useless-145427, r=lqdJakub Beránek-2/+22
Fix wrong spans with external macros in the `dropping_copy_types` lint This PR fixes some wrong spans manipulations when external macros are involved. Specifically we didn't make sure the spans had the same context, which kind-of make our spans manipulations go wrong and produce weird spans. We fix that by making sure they have the same context. Fixes https://github.com/rust-lang/rust/issues/145427
2025-08-15Rollup merge of #145426 - AMS21:fix_typos_bootstrap_example, r=lqdJakub Beránek-2/+2
Fix typos in bootstrap.example.toml Founds these small typos while looking around. `equivelent` -> `equivalent` `recommeded` -> `recommended` cheers :)
2025-08-15Rollup merge of #145413 - joshtriplett:bootstrap-reduce-deps, r=clubby789Jakub Beránek-52/+24
bootstrap: Reduce dependencies Eliminate the `fd-lock` dependency by using the new native locking in std. Eliminate the `xattr` dependency by turning off a feature flag in `tar`, since the tarballs that we extract with bootstrap don't need it.
2025-08-15Rollup merge of #145412 - tgross35:win-tid, r=ChrisDentonJakub Beránek-3/+3
Windows: Replace `GetThreadId`+`GetCurrentThread` with `GetCurrentThreadId` Reference: https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-getcurrentthreadid
2025-08-15Rollup merge of #145408 - Kobzol:deduplicate-search-paths, r=petrochenkovJakub Beránek-12/+29
Deduplicate -L search paths For each -L passed to the compiler, we eagerly scan the whole directory. If it has a lot of files, that results in a lot of allocations. So it's needless to do this if some -L paths are actually duplicated (which can happen e.g. in the situation in the linked issue). This PR both deduplicates the args, and also teaches rustdoc not to pass duplicated args to merged doctests. Fixes: https://github.com/rust-lang/rust/issues/145375
2025-08-15Rollup merge of #145340 - Kobzol:bootstrap-codegen-backend-check-split, ↵Jakub Beránek-170/+91
r=jieyouxu Split codegen backend check step into two and don't run it with `x check compiler` This reduces the amount of work that is done during `x check compiler`. We still check both backends during `x check` by defaut, even if they are not in `rust.codegen-backends`, as just checking them shouldn't require expensive preparations, like building GCC. r? `@jieyouxu`
2025-08-15Rollup merge of #145311 - marcoieni:clean-disk-in-background-windows, r=KobzolJakub Beránek-1/+184
ci: clean windows disk space in background
2025-08-15Rollup merge of #145310 - Kobzol:compiler-for-revamp, r=jieyouxuJakub Beránek-93/+86
Reduce usage of `compiler_for` in bootstrap While working on refactoring/fixing `dist` steps, I realized that `build.full-bootstrap` does much more than it should, and that it its documentation is wrong. It seems that the main purpose of this option should be to enable/disable stdlib/compiler uplifting (https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Purpose.20of.20.60build.2Efull-bootstrap.60/with/533985624), but currently it also affects staging, or more precisely which compiler will be used to build selected steps, because this option is used in the cursed `compiler_for` function. I would like to change the option it so that it *only* affects uplifting, and doesn't affect stage selection, which I (partially) did in this PR. I removed the usage of `compiler_for` from the `Std` and `Rustc` steps, and explicitly implemented uplifting, without going through `compiler_for`. The only remaining usages of `compiler_for` are in dist steps (which I'm currently refactoring, will send a PR later) and test steps (which I will take a look at after dist). After that we can finally remove the function. I tried to document the case when uplifting was happening during cross-compilation, which was very implicit before. I also did a slight change in the uplifting logic for rustc when cross-compiling. Before, we would attempt to uplift a stage1 rustc, but that is not really a thing when cross-compiling. r? `@jieyouxu`
2025-08-15Rollup merge of #144210 - Gelbpunkt:thread-stack-size-musl, r=jhprattJakub Beránek-1/+12
std: thread: Return error if setting thread stack size fails Currently, when setting the thread stack size fails, it would be rounded up to the nearest multiple of the page size and the code asserts that the next call to `pthread_attr_setstacksize` succeeds. This may be true for glibc, but it isn't true for musl, which not only enforces a minimum stack size, but also a maximum stack size of `usize::MAX / 4 - PTHREAD_STACK_MIN` [1], triggering the assert rather than erroring gracefully. There isn't any way to handle this properly other than bailing out and letting the user know it didn't succeed. [1]: https://git.musl-libc.org/cgit/musl/tree/src/thread/pthread_attr_setstacksize.c#n5