rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names #148279
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oli-obk
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hkBst
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r? hkBst |
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oh heh @bors delegate=hkBst |
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Looks fine now, but please squash your commits. |
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… user-defined function names
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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. |
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@hkBst, just squashed the commits! Thanks again for your review & help :) |
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rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names Resolves rust-lang#148275 by preventing name collisions in the `#[bench]` macro. Previously, a user-defined function named "b" could not be benchmarked because the macro-generated lambda identity collided with the same name. We now generate the lambda ident as `__bench_<function_name>`, ensuring it is always distinct from the user’s function. Because the prefix is applied recursively (e.g. benchmarking `__bench_b` produces a lambda ident `__bench___bench_b`), there is no possible function name that can equal its corresponding lambda ident. This guarantees that the user can safely bench a function of any valid name without risk of identifier collision.
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Rollup of 16 pull requests Successful merges: - #147534 (Implement SIMD funnel shifts in const-eval/Miri) - #147686 (update isolate_highest_one for NonZero<T>) - #148020 (Show backtrace on allocation failures when possible) - #148204 (Modify contributor email entries in .mailmap) - #148230 (rustdoc: Properly highlight shebang, frontmatter & weak keywords in source code pages and code blocks) - #148279 (rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names) - #148555 (Fix rust-by-example spanish translation) - #148556 (Fix suggestion for returning async closures) - #148585 ([rustdoc] Replace `print` methods with functions to improve code readability) - #148600 (re-use `self.get_all_attrs` result for pass indirectly attribute) - #148612 (Add note for identifier with attempted hygiene violation) - #148613 (Switch hexagon targets to rust-lld) - #148619 (Enable std locking functions on AIX) - #148644 ([bootstrap] Make `--open` option work with `doc src/tools/error_index_generator`) - #148649 (don't completely reset `HeadUsages`) - #148675 (Remove eslint-js from npm dependencies) r? `@ghost` `@rustbot` modify labels: rollup
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rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names Resolves rust-lang#148275 by preventing name collisions in the `#[bench]` macro. Previously, a user-defined function named "b" could not be benchmarked because the macro-generated lambda identity collided with the same name. We now generate the lambda ident as `__bench_<function_name>`, ensuring it is always distinct from the user’s function. Because the prefix is applied recursively (e.g. benchmarking `__bench_b` produces a lambda ident `__bench___bench_b`), there is no possible function name that can equal its corresponding lambda ident. This guarantees that the user can safely bench a function of any valid name without risk of identifier collision.
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rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names Resolves rust-lang#148275 by preventing name collisions in the `#[bench]` macro. Previously, a user-defined function named "b" could not be benchmarked because the macro-generated lambda identity collided with the same name. We now generate the lambda ident as `__bench_<function_name>`, ensuring it is always distinct from the user’s function. Because the prefix is applied recursively (e.g. benchmarking `__bench_b` produces a lambda ident `__bench___bench_b`), there is no possible function name that can equal its corresponding lambda ident. This guarantees that the user can safely bench a function of any valid name without risk of identifier collision.
matthiaskrgr
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Nov 8, 2025
rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names Resolves rust-lang#148275 by preventing name collisions in the `#[bench]` macro. Previously, a user-defined function named "b" could not be benchmarked because the macro-generated lambda identity collided with the same name. We now generate the lambda ident as `__bench_<function_name>`, ensuring it is always distinct from the user’s function. Because the prefix is applied recursively (e.g. benchmarking `__bench_b` produces a lambda ident `__bench___bench_b`), there is no possible function name that can equal its corresponding lambda ident. This guarantees that the user can safely bench a function of any valid name without risk of identifier collision.
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Nov 9, 2025
rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names Resolves rust-lang#148275 by preventing name collisions in the `#[bench]` macro. Previously, a user-defined function named "b" could not be benchmarked because the macro-generated lambda identity collided with the same name. We now generate the lambda ident as `__bench_<function_name>`, ensuring it is always distinct from the user’s function. Because the prefix is applied recursively (e.g. benchmarking `__bench_b` produces a lambda ident `__bench___bench_b`), there is no possible function name that can equal its corresponding lambda ident. This guarantees that the user can safely bench a function of any valid name without risk of identifier collision.
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Rollup of 22 pull requests Successful merges: - #128666 (Add `overflow_checks` intrinsic) - #146305 (Add correct suggestion for multi-references for self type in method) - #147179 ([DebugInfo] Fix container types failing to find template args) - #147743 (Show packed field alignment in mir_transform_unaligned_packed_ref) - #148079 (Rename `downcast_[ref|mut]_unchecked` -> `downcast_unchecked_[ref|mut]`) - #148084 (Optimize path components iteration on platforms that don't have prefixes) - #148126 (Fix rust stdlib build failing for VxWorks) - #148204 (Modify contributor email entries in .mailmap) - #148279 (rustc_builtin_macros: rename bench parameter to avoid collisions with user-defined function names) - #148333 (constify result unwrap unchecked) - #148539 (Add Allocator proxy impls for Box, Rc, and Arc) - #148601 (`invalid_atomic_ordering`: also lint `update` & `try_update`) - #148612 (Add note for identifier with attempted hygiene violation) - #148613 (Switch hexagon targets to rust-lld) - #148619 (Enable std locking functions on AIX) - #148644 ([bootstrap] Make `--open` option work with `doc src/tools/error_index_generator`) - #148649 (don't completely reset `HeadUsages`) - #148673 (Remove a remnant of `dyn*` from the parser) - #148675 (Remove eslint-js from npm dependencies) - #148680 (Recover `[T: N]` as `[T; N]`) - #148688 (Remove unused argument `features` from `eval_config_entry`) - #148711 (Use the current lint note id when parsing `cfg!()`) r? `@ghost` `@rustbot` modify labels: rollup
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Resolves #148275 by preventing name collisions in the
#[bench]macro.Previously, a user-defined function named "b" could not be benchmarked because
the macro-generated lambda identity collided with the same name. We now generate
the lambda ident as
__bench_<function_name>, ensuring it is always distinctfrom the user’s function.
Because the prefix is applied recursively (e.g. benchmarking
__bench_bproduces a lambda ident
__bench___bench_b), there is no possible functionname that can equal its corresponding lambda ident. This guarantees that
the user can safely bench a function of any valid name without risk of
identifier collision.