Crate linkme

  

A library for safe cross-platform linker shenanigans.

Platform support

Component	Linux	macOS	Windows	FreeBSD	OpenBSD	illumos	Other…†
Distributed slice	💚	💚	💚	💚	💚	💚

^† We welcome PRs adding support for any platforms not listed here.

Distributed slice

A distributed slice is a collection of static elements that are gathered into a contiguous section of the binary by the linker. Slice elements may be defined individually from anywhere in the dependency graph of the final binary.

Refer to linkme::DistributedSlice for complete details of the API. The basic idea is as follows.

A static distributed slice is declared by writing #[distributed_slice] on a static item whose type is [T] for some type T.

use linkme::distributed_slice;

#[distributed_slice]
pub static BENCHMARKS: [fn(&mut Bencher)];

Slice elements may be registered into a distributed slice by a #[distributed_slice(...)] attribute in which the path to the distributed slice is given in the parentheses. The initializer is required to be a const expression.

use linkme::distributed_slice;
use other_crate::BENCHMARKS;

#[distributed_slice(BENCHMARKS)]
static BENCH_DESERIALIZE: fn(&mut Bencher) = bench_deserialize;

fn bench_deserialize(b: &mut Bencher) {
    /* ... */
}

The distributed slice behaves in all ways like &'static [T].

fn main() {
    // Iterate the elements.
    for bench in BENCHMARKS {
        /* ... */
    }

    // Index into the elements.
    let first = BENCHMARKS[0];

    // Slice the elements.
    let except_first = &BENCHMARKS[1..];

    // Invoke methods on the underlying slice.
    let len = BENCHMARKS.len();
}

Workaround for buggy IDEs

JetBrains’s Rust IDE uses an outdated Rust parser that treats distributed slice declarations as invalid syntax, despite being supported in stable rustc for over 3.5 years. See https://youtrack.jetbrains.com/issue/RUST-12953.

If you hit this, you can work around it by adding a dummy initializer expression to the slice.

#[distributed_slice]
pub static BENCHMARKS: [fn(&mut Bencher)] = [..];
                                          ^^^^^^

Structs

• DistributedSlice
  Collection of static elements that are gathered into a contiguous section of the binary by the linker.

Attribute Macros

• distributed_slice