| //! The `wasm32-wasip2` target is the next evolution of the |
| //! wasm32-wasip1 target. While the wasi specification is still under |
| //! active development, the preview 2 iteration is considered an "island |
| //! of stability" that should allow users to rely on it indefinitely. |
| //! |
| //! The `wasi` target is a proposal to define a standardized set of WebAssembly |
| //! component imports that allow it to interoperate with the host system in a |
| //! standardized way. This set of imports is intended to empower WebAssembly |
| //! binaries with host capabilities such as filesystem access, network access, etc. |
| //! |
| //! Wasi Preview 2 relies on the WebAssembly component model which is an extension of |
| //! the core WebAssembly specification which allows interoperability between WebAssembly |
| //! modules (known as "components") through high-level, shared-nothing APIs instead of the |
| //! low-level, shared-everything linear memory model of the core WebAssembly specification. |
| //! |
| //! You can see more about wasi at <https://wasi.dev> and the component model at |
| //! <https://github.com/WebAssembly/component-model>. |
| |
| use crate::spec::{ |
| LinkSelfContainedDefault, RelocModel, Target, TargetMetadata, base, crt_objects, |
| }; |
| |
| pub(crate) fn target() -> Target { |
| let mut options = base::wasm::options(); |
| |
| options.os = "wasi".into(); |
| options.env = "p2".into(); |
| options.linker = Some("wasm-component-ld".into()); |
| |
| options.pre_link_objects_self_contained = crt_objects::pre_wasi_self_contained(); |
| options.post_link_objects_self_contained = crt_objects::post_wasi_self_contained(); |
| |
| // FIXME: Figure out cases in which WASM needs to link with a native toolchain. |
| options.link_self_contained = LinkSelfContainedDefault::True; |
| |
| // Right now this is a bit of a workaround but we're currently saying that |
| // the target by default has a static crt which we're taking as a signal |
| // for "use the bundled crt". If that's turned off then the system's crt |
| // will be used, but this means that default usage of this target doesn't |
| // need an external compiler but it's still interoperable with an external |
| // compiler if configured correctly. |
| options.crt_static_default = true; |
| options.crt_static_respected = true; |
| |
| // Allow `+crt-static` to create a "cdylib" output which is just a wasm file |
| // without a main function. |
| options.crt_static_allows_dylibs = true; |
| |
| // WASI's `sys::args::init` function ignores its arguments; instead, |
| // `args::args()` makes the WASI API calls itself. |
| options.main_needs_argc_argv = false; |
| |
| // And, WASI mangles the name of "main" to distinguish between different |
| // signatures. |
| options.entry_name = "__main_void".into(); |
| |
| // Default to PIC unlike base wasm. This makes precompiled objects such as |
| // the standard library more suitable to be used with shared libraries a la |
| // emscripten's dynamic linking convention. |
| options.relocation_model = RelocModel::Pic; |
| |
| Target { |
| llvm_target: "wasm32-wasip2".into(), |
| metadata: TargetMetadata { |
| description: Some("WebAssembly".into()), |
| tier: Some(3), |
| host_tools: Some(false), |
| std: Some(true), |
| }, |
| pointer_width: 32, |
| data_layout: "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-i128:128-n32:64-S128-ni:1:10:20".into(), |
| arch: "wasm32".into(), |
| options, |
| } |
| } |