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-rw-r--r--vendor/rustix/build.rs250
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()
-}