diff options
Diffstat (limited to '')
7 files changed, 44 insertions, 79 deletions
diff --git a/src/doc/unstable-book/src/compiler-flags/dylib-lto.md b/src/doc/unstable-book/src/compiler-flags/dylib-lto.md new file mode 100644 index 000000000..f69ea334f --- /dev/null +++ b/src/doc/unstable-book/src/compiler-flags/dylib-lto.md @@ -0,0 +1,4 @@ +## `dylib-lto` + +This option enables using LTO for the `dylib` crate type. This is currently only used for compiling +`rustc` itself (more specifically, the `librustc_driver` dylib). diff --git a/src/doc/unstable-book/src/compiler-flags/self-profile-events.md b/src/doc/unstable-book/src/compiler-flags/self-profile-events.md index 3ce18743b..3e644f786 100644 --- a/src/doc/unstable-book/src/compiler-flags/self-profile-events.md +++ b/src/doc/unstable-book/src/compiler-flags/self-profile-events.md @@ -41,7 +41,7 @@ $ rustc -Zself-profile -Zself-profile-events=default,args - `llvm` - Adds tracing information about LLVM passes and codegeneration. - - Disabled by default because this only works when `-Znew-llvm-pass-manager` is enabled. + - Disabled by default because this significantly increases the trace file size. ## Event synonyms diff --git a/src/doc/unstable-book/src/language-features/arbitrary-enum-discriminant.md b/src/doc/unstable-book/src/language-features/arbitrary-enum-discriminant.md deleted file mode 100644 index e0bb78227..000000000 --- a/src/doc/unstable-book/src/language-features/arbitrary-enum-discriminant.md +++ /dev/null @@ -1,37 +0,0 @@ -# `arbitrary_enum_discriminant` - -The tracking issue for this feature is: [#60553] - -[#60553]: https://github.com/rust-lang/rust/issues/60553 - ------------------------- - -The `arbitrary_enum_discriminant` feature permits tuple-like and -struct-like enum variants with `#[repr(<int-type>)]` to have explicit discriminants. - -## Examples - -```rust -#![feature(arbitrary_enum_discriminant)] - -#[allow(dead_code)] -#[repr(u8)] -enum Enum { - Unit = 3, - Tuple(u16) = 2, - Struct { - a: u8, - b: u16, - } = 1, -} - -impl Enum { - fn tag(&self) -> u8 { - unsafe { *(self as *const Self as *const u8) } - } -} - -assert_eq!(3, Enum::Unit.tag()); -assert_eq!(2, Enum::Tuple(5).tag()); -assert_eq!(1, Enum::Struct{a: 7, b: 11}.tag()); -``` diff --git a/src/doc/unstable-book/src/language-features/asm-sym.md b/src/doc/unstable-book/src/language-features/asm-sym.md deleted file mode 100644 index 103d91caf..000000000 --- a/src/doc/unstable-book/src/language-features/asm-sym.md +++ /dev/null @@ -1,13 +0,0 @@ -# `asm_sym` - -The tracking issue for this feature is: [#93333] - -[#93333]: https://github.com/rust-lang/rust/issues/93333 - ------------------------- - -This feature adds a `sym <path>` operand type to `asm!` and `global_asm!`. -- `<path>` must refer to a `fn` or `static`. -- A mangled symbol name referring to the item is substituted into the asm template string. -- The substituted string does not include any modifiers (e.g. GOT, PLT, relocations, etc). -- `<path>` is allowed to point to a `#[thread_local]` static, in which case the asm code can combine the symbol with relocations (e.g. `@plt`, `@TPOFF`) to read from thread-local data. diff --git a/src/doc/unstable-book/src/language-features/half-open-range-patterns-in-slices.md b/src/doc/unstable-book/src/language-features/half-open-range-patterns-in-slices.md new file mode 100644 index 000000000..56a1a97df --- /dev/null +++ b/src/doc/unstable-book/src/language-features/half-open-range-patterns-in-slices.md @@ -0,0 +1,30 @@ +# `half_open_range_patterns_in_slices` + +The tracking issue for this feature is: [#67264] +It is part of the `exclusive_range_pattern` feature, +tracked at [#37854]. + +[#67264]: https://github.com/rust-lang/rust/issues/67264 +[#37854]: https://github.com/rust-lang/rust/issues/37854 +----- + +This feature allow using top-level half-open range patterns in slices. + +```rust +#![feature(half_open_range_patterns_in_slices)] +#![feature(exclusive_range_pattern)] + +fn main() { + let xs = [13, 1, 5, 2, 3, 1, 21, 8]; + let [a @ 3.., b @ ..3, c @ 4..6, ..] = xs else { return; }; +} +``` + +Note that this feature is not required if the patterns are wrapped between parenthesis. + +```rust +fn main() { + let xs = [13, 1]; + let [(a @ 3..), c] = xs else { return; }; +} +``` diff --git a/src/doc/unstable-book/src/language-features/half-open-range-patterns.md b/src/doc/unstable-book/src/language-features/half-open-range-patterns.md deleted file mode 100644 index 3b16dd049..000000000 --- a/src/doc/unstable-book/src/language-features/half-open-range-patterns.md +++ /dev/null @@ -1,27 +0,0 @@ -# `half_open_range_patterns` - -The tracking issue for this feature is: [#67264] -It is part of the `#![exclusive_range_pattern]` feature, -tracked at [#37854]. - -[#67264]: https://github.com/rust-lang/rust/issues/67264 -[#37854]: https://github.com/rust-lang/rust/issues/37854 ------ - -The `half_open_range_patterns` feature allows RangeTo patterns -(`..10`) to be used in appropriate pattern matching contexts. -This requires also enabling the `exclusive_range_pattern` feature. - -It also enabled RangeFrom patterns but that has since been -stabilized. - -```rust -#![feature(half_open_range_patterns)] -#![feature(exclusive_range_pattern)] - let x = 5; - match x { - ..0 => println!("negative!"), // "RangeTo" pattern. Unstable. - 0 => println!("zero!"), - 1.. => println!("positive!"), // "RangeFrom" pattern. Stable. - } -``` diff --git a/src/doc/unstable-book/src/language-features/unix-sigpipe.md b/src/doc/unstable-book/src/language-features/unix-sigpipe.md index aa39b6eb2..7ed6a7de8 100644 --- a/src/doc/unstable-book/src/language-features/unix-sigpipe.md +++ b/src/doc/unstable-book/src/language-features/unix-sigpipe.md @@ -36,7 +36,7 @@ hello world Set the `SIGPIPE` handler to `SIG_IGN` before invoking `fn main()`. This will result in `ErrorKind::BrokenPipe` errors if you program tries to write to a closed pipe. This is normally what you want if you for example write socket servers, socket clients, or pipe peers. -This is what libstd has done by default since 2014. Omitting `#[unix_sigpipe = "..."]` is the same as having `#[unix_sigpipe = "sig_ign"]`. +This is what libstd has done by default since 2014. (However, see the note on child processes below.) ### Example @@ -52,3 +52,11 @@ hello world thread 'main' panicked at 'failed printing to stdout: Broken pipe (os error 32)', library/std/src/io/stdio.rs:1016:9 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace ``` + +### Note on child processes + +When spawning child processes, the legacy Rust behavior if `#[unix_sigpipe]` is not specified is to +reset `SIGPIPE` to `SIG_DFL`. + +If `#[unix_sigpipe = "..."]` is specified, no matter what its value is, the signal disposition of +`SIGPIPE` is no longer reset. This means that the child inherits the parent's `SIGPIPE` behavior. |