library: Migrate from cfg_if to cfg_select
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Migrate the standard library from using the external `cfg_if` crate to
using the now-built-in `cfg_select` macro.
This does not yet eliminate the dependency from
`library/std/Cargo.toml`, because while the standard library itself no
longer uses `cfg_if`, it also incorporates the `backtrace` crate, which
does.
Migration assisted by the following vim command (after selecting the
full `cfg_if!` invocation):
```
'<,'>s/\(cfg_if::\)\?cfg_if/cfg_select/ | '<,'>s/^\( *\)} else {/\1}\r\1_ => {/c | '<,'>s/^\( *\)} else if #\[cfg(\(.*\))\] /\1}\r\1\2 => /e | '<,'>s/if #\[cfg(\(.*\))\] {/\1 => {/e
```
This is imperfect, but substantially accelerated the process. This
prompts for confirmation on the `} else {` since that can also appear
inside one of the arms. This also requires manual intervention to handle
any multi-line conditions.
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r? @Amanieu |
The previous code inside `cfg_if!` wasn't indented, so the conversion to `cfg_select!` left it not indented. Indent it.
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@bors r=Amanieu p=1 |
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library: Migrate from `cfg_if` to `cfg_select`
Migrate the standard library from using the external `cfg_if` crate to using the now-built-in `cfg_select` macro.
This does not yet eliminate the dependency from `library/std/Cargo.toml`, because while the standard library itself no longer uses `cfg_if`, it also incorporates the `backtrace` crate, which does.
Migration assisted by the following vim command (after selecting the full `cfg_if!` invocation):
```
'<,'>s/\(cfg_if::\)\?cfg_if/cfg_select/ | '<,'>s/^\( *\)} else {/\1}\r\1_ => {/c | '<,'>s/^\( *\)} else if #\[cfg(\(.*\))\] /\1}\r\1\2 => /e | '<,'>s/if #\[cfg(\(.*\))\] {/\1 => {/e
```
This is imperfect, but substantially accelerated the process. This prompts for confirmation on the `} else {` since that can also appear inside one of the arms. This also requires manual intervention to handle any multi-line conditions.
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Rollup of 10 pull requests Successful merges: - #144476 (rustdoc-search: search backend with partitioned suffix tree) - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) - #145489 (library: Migrate from `cfg_if` to `cfg_select`) r? `@ghost` `@rustbot` modify labels: rollup
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Failed in rollup: #145521 (comment) |
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library: Migrate from `cfg_if` to `cfg_select` try-job: x86_64-gnu-llvm-19-3
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💔 Test for b3311ae failed: CI. Failed jobs:
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@bors r=Amanieu rollup=iffy p=1 |
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Migrate the standard library from using the external
cfg_ifcrate to using the now-built-incfg_selectmacro.This does not yet eliminate the dependency from
library/std/Cargo.toml, because while the standard library itself no longer usescfg_if, it also incorporates thebacktracecrate, which does.Migration assisted by the following vim command (after selecting the full
cfg_if!invocation):This is imperfect, but substantially accelerated the process. This prompts for confirmation on the
} else {since that can also appear inside one of the arms. This also requires manual intervention to handle any multi-line conditions.