| //! A "bare wasm" target representing a WebAssembly output that makes zero |
| //! assumptions about its environment. |
| //! |
| //! The `wasm32-unknown-unknown` target is intended to encapsulate use cases |
| //! that do not rely on any imported functionality. The binaries generated are |
| //! entirely self-contained by default when using the standard library. Although |
| //! the standard library is available, most of it returns an error immediately |
| //! (e.g. trying to create a TCP stream or something like that). |
| //! |
| //! This target is more or less managed by the Rust and WebAssembly Working |
| //! Group nowadays at https://github.com/rustwasm. |
| |
| use super::{LldFlavor, LinkerFlavor, Target}; |
| use super::wasm32_base; |
| |
| pub fn target() -> Result<Target, String> { |
| let mut options = wasm32_base::options(); |
| let clang_args = options.pre_link_args.get_mut(&LinkerFlavor::Gcc).unwrap(); |
| |
| // Make sure clang uses LLD as its linker and is configured appropriately |
| // otherwise |
| clang_args.push("--target=wasm32-unknown-unknown".to_string()); |
| |
| // Disable attempting to link crt1.o since it typically isn't present and |
| // isn't needed currently. |
| clang_args.push("-nostdlib".to_string()); |
| |
| // For now this target just never has an entry symbol no matter the output |
| // type, so unconditionally pass this. |
| clang_args.push("-Wl,--no-entry".to_string()); |
| options.pre_link_args.get_mut(&LinkerFlavor::Lld(LldFlavor::Wasm)) |
| .unwrap() |
| .push("--no-entry".to_string()); |
| |
| Ok(Target { |
| llvm_target: "wasm32-unknown-unknown".to_string(), |
| target_endian: "little".to_string(), |
| target_pointer_width: "32".to_string(), |
| target_c_int_width: "32".to_string(), |
| target_os: "unknown".to_string(), |
| target_env: String::new(), |
| target_vendor: "unknown".to_string(), |
| data_layout: "e-m:e-p:32:32-i64:64-n32:64-S128".to_string(), |
| arch: "wasm32".to_string(), |
| linker_flavor: LinkerFlavor::Lld(LldFlavor::Wasm), |
| options, |
| }) |
| } |