45bf1ed1a1
This commit is an implementation of [RFC 1183][rfc] which allows swapping out the default allocator on nightly Rust. No new stable surface area should be added as a part of this commit. [rfc]: https://github.com/rust-lang/rfcs/pull/1183 Two new attributes have been added to the compiler: * `#![needs_allocator]` - this is used by liballoc (and likely only liballoc) to indicate that it requires an allocator crate to be in scope. * `#![allocator]` - this is a indicator that the crate is an allocator which can satisfy the `needs_allocator` attribute above. The ABI of the allocator crate is defined to be a set of symbols that implement the standard Rust allocation/deallocation functions. The symbols are not currently checked for exhaustiveness or typechecked. There are also a number of restrictions on these crates: * An allocator crate cannot transitively depend on a crate that is flagged as needing an allocator (e.g. allocator crates can't depend on liballoc). * There can only be one explicitly linked allocator in a final image. * If no allocator is explicitly requested one will be injected on behalf of the compiler. Binaries and Rust dylibs will use jemalloc by default where available and staticlibs/other dylibs will use the system allocator by default. Two allocators are provided by the distribution by default, `alloc_system` and `alloc_jemalloc` which operate as advertised. Closes #27389
15 lines
550 B
Rust
15 lines
550 B
Rust
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
|
|
// file at the top-level directory of this distribution and at
|
|
// http://rust-lang.org/COPYRIGHT.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
|
// option. This file may not be copied, modified, or distributed
|
|
// except according to those terms.
|
|
|
|
#![needs_allocator] //~ ERROR the `#[needs_allocator]` attribute is
|
|
|
|
fn main() {}
|
|
|