std: Switch implementations of thread_local! for WASI#159733
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alexcrichton wants to merge 1 commit into
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std: Switch implementations of thread_local! for WASI#159733alexcrichton wants to merge 1 commit into
thread_local! for WASI#159733alexcrichton wants to merge 1 commit into
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This commit is a change for all WASI targets to use a different underlying implementation in the standard library for `thread_local!`. Previously all wasm targets, without the `atomics` feature, were funneled into the `no_threads` implementation and various fallbacks in the `thread_local` module. The upcoming `wasm32-wasip3` target, however, will actually have threads and will need different treatment. Additionally the modules that `wasm32-wasip3` needs all already work on all other WASI targets as well -- for example the `pthread_*` symbols needed to manage destructors are exposed by `wasi-libc`. The end result is that the `wasm32-wasip3` target will be "ready for threads" as soon as `wasi-libc` has support. Other targets shouldn't have any functional difference from before, too.
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r? @clarfonthey rustbot has assigned @clarfonthey. Use Why was this reviewer chosen?The reviewer was selected based on:
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This module's logic is a bit annoying to follow, although everything appears reasonable to me. @bors r+ rollup |
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…=clarfonthey std: Switch implementations of `thread_local!` for WASI This commit is a change for all WASI targets to use a different underlying implementation in the standard library for `thread_local!`. Previously all wasm targets, without the `atomics` feature, were funneled into the `no_threads` implementation and various fallbacks in the `thread_local` module. The upcoming `wasm32-wasip3` target, however, will actually have threads and will need different treatment. Additionally the modules that `wasm32-wasip3` needs all already work on all other WASI targets as well -- for example the `pthread_*` symbols needed to manage destructors are exposed by `wasi-libc`. The end result is that the `wasm32-wasip3` target will be "ready for threads" as soon as `wasi-libc` has support. Other targets shouldn't have any functional difference from before, too.
JonathanBrouwer
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…=clarfonthey std: Switch implementations of `thread_local!` for WASI This commit is a change for all WASI targets to use a different underlying implementation in the standard library for `thread_local!`. Previously all wasm targets, without the `atomics` feature, were funneled into the `no_threads` implementation and various fallbacks in the `thread_local` module. The upcoming `wasm32-wasip3` target, however, will actually have threads and will need different treatment. Additionally the modules that `wasm32-wasip3` needs all already work on all other WASI targets as well -- for example the `pthread_*` symbols needed to manage destructors are exposed by `wasi-libc`. The end result is that the `wasm32-wasip3` target will be "ready for threads" as soon as `wasi-libc` has support. Other targets shouldn't have any functional difference from before, too.
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…uwer Rollup of 24 pull requests Successful merges: - #159638 (bootstrap: Split the `Step` trait into multiple traits) - #159774 (rustc_trait_selection: fix trait solver hang caused by degenerate obligations) - #159837 (line-tables-only test: check that the line number matches the function name) - #159946 (Update Enzyme submodule to imporve llvm-cov) - #159617 (Fix up `#[linkage]` target checking) - #159733 (std: Switch implementations of `thread_local!` for WASI) - #159783 (Check unsafe impls on safe EIIs) - #159810 (Add tuple never coercion collection regression test) - #159821 (Update expect message using the recommended style in binary_heap module) - #159826 (Remove redundant `#[rustc_paren_sugar]` feature gate) - #159846 (Implement `str::copy_from_str`) - #159849 (rustc_parse: Stop returning `Option` from statement parsing) - #159853 (Updated expect messages for `CString` struct and method documentation) - #159875 (More cleanup in `rustc_attr_parsing`) - #159882 (Update expect messages in library/alloc/boxed.rs and library/alloc/string.rs to follow the style guide) - #159891 (Split multiline derives into std/rustc macros) - #159893 (Fix `find_attr` hygiene and `rustc_hir` cleanups) - #159895 (rustc-dev-guide subtree update) - #159902 (Clarify that the expected runtime symbols signature is for the current target only) - #159914 (Fix error in diagnostic on_unmatched_args) - #159917 (spare capacity mut constification) - #159918 (rename abort_unwind → abort_on_unwind) - #159936 (Minor `rustc_ast::ast` doc cleanups) - #159945 (Update expect messages in library/core/src/ptr/non_null.rs)
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…uwer Rollup of 24 pull requests Successful merges: - #159638 (bootstrap: Split the `Step` trait into multiple traits) - #159774 (rustc_trait_selection: fix trait solver hang caused by degenerate obligations) - #159837 (line-tables-only test: check that the line number matches the function name) - #159946 (Update Enzyme submodule to imporve llvm-cov) - #159617 (Fix up `#[linkage]` target checking) - #159733 (std: Switch implementations of `thread_local!` for WASI) - #159783 (Check unsafe impls on safe EIIs) - #159810 (Add tuple never coercion collection regression test) - #159821 (Update expect message using the recommended style in binary_heap module) - #159826 (Remove redundant `#[rustc_paren_sugar]` feature gate) - #159846 (Implement `str::copy_from_str`) - #159849 (rustc_parse: Stop returning `Option` from statement parsing) - #159853 (Updated expect messages for `CString` struct and method documentation) - #159875 (More cleanup in `rustc_attr_parsing`) - #159882 (Update expect messages in library/alloc/boxed.rs and library/alloc/string.rs to follow the style guide) - #159891 (Split multiline derives into std/rustc macros) - #159893 (Fix `find_attr` hygiene and `rustc_hir` cleanups) - #159895 (rustc-dev-guide subtree update) - #159902 (Clarify that the expected runtime symbols signature is for the current target only) - #159914 (Fix error in diagnostic on_unmatched_args) - #159917 (spare capacity mut constification) - #159918 (rename abort_unwind → abort_on_unwind) - #159936 (Minor `rustc_ast::ast` doc cleanups) - #159945 (Update expect messages in library/core/src/ptr/non_null.rs)
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This commit is a change for all WASI targets to use a different underlying implementation in the standard library for
thread_local!. Previously all wasm targets, without theatomicsfeature, were funneled into theno_threadsimplementation and various fallbacks in thethread_localmodule. The upcomingwasm32-wasip3target, however, will actually have threads and will need different treatment. Additionally the modules thatwasm32-wasip3needs all already work on all other WASI targets as well -- for example thepthread_*symbols needed to manage destructors are exposed bywasi-libc.The end result is that the
wasm32-wasip3target will be "ready for threads" as soon aswasi-libchas support. Other targets shouldn't have any functional difference from before, too.