diff options
Diffstat (limited to 'vendor/rustix/build.rs')
-rw-r--r-- | vendor/rustix/build.rs | 250 |
1 files changed, 0 insertions, 250 deletions
diff --git a/vendor/rustix/build.rs b/vendor/rustix/build.rs deleted file mode 100644 index d95f9a9..0000000 --- a/vendor/rustix/build.rs +++ /dev/null @@ -1,250 +0,0 @@ -use std::env::var; -use std::io::Write; - -/// The directory for inline asm. -const ASM_PATH: &str = "src/backend/linux_raw/arch"; - -fn main() { - // Don't rerun this on changes other than build.rs, as we only depend on - // the rustc version. - println!("cargo:rerun-if-changed=build.rs"); - - // Gather target information. - let arch = var("CARGO_CFG_TARGET_ARCH").unwrap(); - let env = var("CARGO_CFG_TARGET_ENV").unwrap(); - let inline_asm_name = format!("{}/{}.rs", ASM_PATH, arch); - let inline_asm_name_present = std::fs::metadata(inline_asm_name).is_ok(); - let os = var("CARGO_CFG_TARGET_OS").unwrap(); - let pointer_width = var("CARGO_CFG_TARGET_POINTER_WIDTH").unwrap(); - let endian = var("CARGO_CFG_TARGET_ENDIAN").unwrap(); - - // Check for special target variants. - let is_x32 = arch == "x86_64" && pointer_width == "32"; - let is_arm64_ilp32 = arch == "aarch64" && pointer_width == "32"; - let is_powerpc64be = arch == "powerpc64" && endian == "big"; - let is_mipseb = (arch == "mips" || arch == "mips32r6") && endian == "big"; - let is_mips64eb = arch.contains("mips64") && endian == "big"; - let is_unsupported_abi = is_x32 || is_arm64_ilp32 || is_powerpc64be || is_mipseb || is_mips64eb; - - // Check for `--features=use-libc`. This allows crate users to enable the - // libc backend. - let feature_use_libc = var("CARGO_FEATURE_USE_LIBC").is_ok(); - - // Check for `RUSTFLAGS=--cfg=rustix_use_libc`. This allows end users to - // enable the libc backend even if rustix is depended on transitively. - let cfg_use_libc = var("CARGO_CFG_RUSTIX_USE_LIBC").is_ok(); - - // Check for `--features=rustc-dep-of-std`. - let rustc_dep_of_std = var("CARGO_FEATURE_RUSTC_DEP_OF_STD").is_ok(); - - // Check for eg. `RUSTFLAGS=--cfg=rustix_use_experimental_features`. This - // is a rustc flag rather than a cargo feature flag because it's - // experimental and not something we want accidentally enabled via - // `--all-features`. - let rustix_use_experimental_features = - var("CARGO_CFG_RUSTIX_USE_EXPERIMENTAL_FEATURES").is_ok(); - - // Check for eg. `RUSTFLAGS=--cfg=rustix_use_experimental_asm`. This is a - // rustc flag rather than a cargo feature flag because it's experimental - // and not something we want accidentally enabled via `--all-features`. - let rustix_use_experimental_asm = var("CARGO_CFG_RUSTIX_USE_EXPERIMENTAL_ASM").is_ok(); - - // Miri doesn't support inline asm, and has builtin support for recognizing - // libc FFI calls, so if we're running under miri, use the libc backend. - let miri = var("CARGO_CFG_MIRI").is_ok(); - - // If experimental features are enabled, auto-detect and use available - // features. - if rustc_dep_of_std { - use_feature("rustc_attrs"); - use_feature("core_intrinsics"); - } else if rustix_use_experimental_features { - use_feature_or_nothing("rustc_attrs"); - use_feature_or_nothing("core_intrinsics"); - } - - // Features needed only in no-std configurations. - #[cfg(not(feature = "std"))] - { - use_feature_or_nothing("core_c_str"); - use_feature_or_nothing("core_ffi_c"); - use_feature_or_nothing("alloc_c_string"); - use_feature_or_nothing("alloc_ffi"); - } - - // Feature needed for testing. - if use_static_assertions() { - use_feature("static_assertions"); - } - - // WASI support can utilize wasi_ext if present. - if os == "wasi" { - use_feature_or_nothing("wasi_ext"); - } - - // If the libc backend is requested, or if we're not on a platform for - // which we have linux_raw support, use the libc backend. - // - // For now Android uses the libc backend; in theory it could use the - // linux_raw backend, but to do that we'll need to figure out how to - // install the toolchain for it. - let libc = feature_use_libc - || cfg_use_libc - || os != "linux" - || !inline_asm_name_present - || is_unsupported_abi - || miri - || ((arch == "powerpc64" || arch.starts_with("mips")) && !rustix_use_experimental_asm); - if libc { - // Use the libc backend. - use_feature("libc"); - } else { - // Use the linux_raw backend. - use_feature("linux_raw"); - if rustix_use_experimental_asm { - use_feature("asm_experimental_arch"); - } - } - - // Detect whether the compiler requires us to use thumb mode on ARM. - if arch == "arm" && use_thumb_mode() { - use_feature("thumb_mode"); - } - - // Rust's libc crate groups some OS's together which have similar APIs; - // create similarly-named features to make `cfg` tests more concise. - let freebsdlike = os == "freebsd" || os == "dragonfly"; - if freebsdlike { - use_feature("freebsdlike"); - } - let netbsdlike = os == "openbsd" || os == "netbsd"; - if netbsdlike { - use_feature("netbsdlike"); - } - let apple = os == "macos" || os == "ios" || os == "tvos" || os == "watchos"; - if apple { - use_feature("apple"); - } - if os == "linux" || os == "l4re" || os == "android" || os == "emscripten" { - use_feature("linux_like"); - } - if os == "solaris" || os == "illumos" { - use_feature("solarish"); - } - if apple || freebsdlike || netbsdlike { - use_feature("bsd"); - } - - // Add some additional common target combinations. - - // Android and "regular" Linux both use the Linux kernel. - if os == "android" || os == "linux" { - use_feature("linux_kernel"); - } - - // These platforms have a 32-bit `time_t`. - if libc - && (arch == "arm" - || arch == "mips" - || arch == "sparc" - || arch == "x86" - || (arch == "wasm32" && os == "emscripten")) - && (apple - || os == "android" - || os == "emscripten" - || os == "haiku" - || env == "gnu" - || (env == "musl" && arch == "x86")) - { - use_feature("fix_y2038"); - } - - println!("cargo:rerun-if-env-changed=CARGO_CFG_RUSTIX_USE_EXPERIMENTAL_ASM"); - println!("cargo:rerun-if-env-changed=CARGO_CFG_RUSTIX_USE_LIBC"); - - // Rerun this script if any of our features or configuration flags change, - // or if the toolchain we used for feature detection changes. - println!("cargo:rerun-if-env-changed=CARGO_FEATURE_USE_LIBC"); - println!("cargo:rerun-if-env-changed=CARGO_FEATURE_RUSTC_DEP_OF_STD"); - println!("cargo:rerun-if-env-changed=CARGO_CFG_MIRI"); -} - -fn use_static_assertions() -> bool { - // `offset_from` was made const in Rust 1.65. - can_compile("const unsafe fn foo(p: *const u8) -> isize { p.offset_from(p) }") -} - -fn use_thumb_mode() -> bool { - // In thumb mode, r7 is reserved. - !can_compile("pub unsafe fn f() { core::arch::asm!(\"udf #16\", in(\"r7\") 0); }") -} - -fn use_feature_or_nothing(feature: &str) { - if has_feature(feature) { - use_feature(feature); - } -} - -fn use_feature(feature: &str) { - println!("cargo:rustc-cfg={}", feature); -} - -/// Test whether the rustc at `var("RUSTC")` supports the given feature. -fn has_feature(feature: &str) -> bool { - can_compile(format!( - "#![allow(stable_features)]\n#![feature({})]", - feature - )) -} - -/// Test whether the rustc at `var("RUSTC")` can compile the given code. -fn can_compile<T: AsRef<str>>(test: T) -> bool { - use std::process::Stdio; - - let out_dir = var("OUT_DIR").unwrap(); - let rustc = var("RUSTC").unwrap(); - let target = var("TARGET").unwrap(); - - // Use `RUSTC_WRAPPER` if it's set, unless it's set to an empty string, as - // documented [here]. - // [here]: https://doc.rust-lang.org/cargo/reference/environment-variables.html#environment-variables-cargo-reads - let wrapper = var("RUSTC_WRAPPER") - .ok() - .and_then(|w| if w.is_empty() { None } else { Some(w) }); - - let mut cmd = if let Some(wrapper) = wrapper { - let mut cmd = std::process::Command::new(wrapper); - // The wrapper's first argument is supposed to be the path to rustc. - cmd.arg(rustc); - cmd - } else { - std::process::Command::new(rustc) - }; - - cmd.arg("--crate-type=rlib") // Don't require `main`. - .arg("--emit=metadata") // Do as little as possible but still parse. - .arg("--target") - .arg(target) - .arg("--out-dir") - .arg(out_dir); // Put the output somewhere inconsequential. - - // If Cargo wants to set RUSTFLAGS, use that. - if let Ok(rustflags) = var("CARGO_ENCODED_RUSTFLAGS") { - if !rustflags.is_empty() { - for arg in rustflags.split('\x1f') { - cmd.arg(arg); - } - } - } - - let mut child = cmd - .arg("-") // Read from stdin. - .stdin(Stdio::piped()) // Stdin is a pipe. - .stderr(Stdio::null()) // Errors from feature detection aren't interesting and can be confusing. - .spawn() - .unwrap(); - - writeln!(child.stdin.take().unwrap(), "{}", test.as_ref()).unwrap(); - - child.wait().unwrap().success() -} |