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Diffstat (limited to 'vendor/proc-macro2/build.rs')
| -rw-r--r-- | vendor/proc-macro2/build.rs | 202 |
1 files changed, 0 insertions, 202 deletions
diff --git a/vendor/proc-macro2/build.rs b/vendor/proc-macro2/build.rs deleted file mode 100644 index 3347f87..0000000 --- a/vendor/proc-macro2/build.rs +++ /dev/null @@ -1,202 +0,0 @@ -// rustc-cfg emitted by the build script: -// -// "wrap_proc_macro" -// Wrap types from libproc_macro rather than polyfilling the whole API. -// Enabled on rustc 1.29+ as long as procmacro2_semver_exempt is not set, -// because we can't emulate the unstable API without emulating everything -// else. Also enabled unconditionally on nightly, in which case the -// procmacro2_semver_exempt surface area is implemented by using the -// nightly-only proc_macro API. -// -// "hygiene" -// Enable Span::mixed_site() and non-dummy behavior of Span::resolved_at -// and Span::located_at. Enabled on Rust 1.45+. -// -// "proc_macro_span" -// Enable non-dummy behavior of Span::start and Span::end methods which -// requires an unstable compiler feature. Enabled when building with -// nightly, unless `-Z allow-feature` in RUSTFLAGS disallows unstable -// features. -// -// "super_unstable" -// Implement the semver exempt API in terms of the nightly-only proc_macro -// API. Enabled when using procmacro2_semver_exempt on a nightly compiler. -// -// "span_locations" -// Provide methods Span::start and Span::end which give the line/column -// location of a token. Enabled by procmacro2_semver_exempt or the -// "span-locations" Cargo cfg. This is behind a cfg because tracking -// location inside spans is a performance hit. -// -// "is_available" -// Use proc_macro::is_available() to detect if the proc macro API is -// available or needs to be polyfilled instead of trying to use the proc -// macro API and catching a panic if it isn't available. Enabled on Rust -// 1.57+. - -use std::env; -use std::ffi::OsString; -use std::path::Path; -use std::process::{self, Command, Stdio}; -use std::str; -use std::u32; - -fn main() { - let rustc = rustc_minor_version().unwrap_or(u32::MAX); - - let docs_rs = env::var_os("DOCS_RS").is_some(); - let semver_exempt = cfg!(procmacro2_semver_exempt) || docs_rs; - if semver_exempt { - // https://github.com/dtolnay/proc-macro2/issues/147 - println!("cargo:rustc-cfg=procmacro2_semver_exempt"); - } - - if semver_exempt || cfg!(feature = "span-locations") { - println!("cargo:rustc-cfg=span_locations"); - } - - if rustc < 57 { - println!("cargo:rustc-cfg=no_is_available"); - } - - if rustc < 66 { - println!("cargo:rustc-cfg=no_source_text"); - } - - if !cfg!(feature = "proc-macro") { - println!("cargo:rerun-if-changed=build.rs"); - return; - } - - println!("cargo:rerun-if-changed=build/probe.rs"); - - let proc_macro_span; - let consider_rustc_bootstrap; - if compile_probe(false) { - // This is a nightly or dev compiler, so it supports unstable features - // regardless of RUSTC_BOOTSTRAP. No need to rerun build script if - // RUSTC_BOOTSTRAP is changed. - proc_macro_span = true; - consider_rustc_bootstrap = false; - } else if let Some(rustc_bootstrap) = env::var_os("RUSTC_BOOTSTRAP") { - if compile_probe(true) { - // This is a stable or beta compiler for which the user has set - // RUSTC_BOOTSTRAP to turn on unstable features. Rerun build script - // if they change it. - proc_macro_span = true; - consider_rustc_bootstrap = true; - } else if rustc_bootstrap == "1" { - // This compiler does not support the proc macro Span API in the - // form that proc-macro2 expects. No need to pay attention to - // RUSTC_BOOTSTRAP. - proc_macro_span = false; - consider_rustc_bootstrap = false; - } else { - // This is a stable or beta compiler for which RUSTC_BOOTSTRAP is - // set to restrict the use of unstable features by this crate. - proc_macro_span = false; - consider_rustc_bootstrap = true; - } - } else { - // Without RUSTC_BOOTSTRAP, this compiler does not support the proc - // macro Span API in the form that proc-macro2 expects, but try again if - // the user turns on unstable features. - proc_macro_span = false; - consider_rustc_bootstrap = true; - } - - if proc_macro_span || !semver_exempt { - println!("cargo:rustc-cfg=wrap_proc_macro"); - } - - if proc_macro_span { - println!("cargo:rustc-cfg=proc_macro_span"); - } - - if semver_exempt && proc_macro_span { - println!("cargo:rustc-cfg=super_unstable"); - } - - if consider_rustc_bootstrap { - println!("cargo:rerun-if-env-changed=RUSTC_BOOTSTRAP"); - } -} - -fn compile_probe(rustc_bootstrap: bool) -> bool { - if env::var_os("RUSTC_STAGE").is_some() { - // We are running inside rustc bootstrap. This is a highly non-standard - // environment with issues such as: - // - // https://github.com/rust-lang/cargo/issues/11138 - // https://github.com/rust-lang/rust/issues/114839 - // - // Let's just not use nightly features here. - return false; - } - - let rustc = cargo_env_var("RUSTC"); - let out_dir = cargo_env_var("OUT_DIR"); - let probefile = Path::new("build").join("probe.rs"); - - // Make sure to pick up Cargo rustc configuration. - let mut cmd = if let Some(wrapper) = env::var_os("RUSTC_WRAPPER") { - let mut cmd = Command::new(wrapper); - // The wrapper's first argument is supposed to be the path to rustc. - cmd.arg(rustc); - cmd - } else { - Command::new(rustc) - }; - - if !rustc_bootstrap { - cmd.env_remove("RUSTC_BOOTSTRAP"); - } - - cmd.stderr(Stdio::null()) - .arg("--edition=2021") - .arg("--crate-name=proc_macro2") - .arg("--crate-type=lib") - .arg("--emit=dep-info,metadata") - .arg("--out-dir") - .arg(out_dir) - .arg(probefile); - - if let Some(target) = env::var_os("TARGET") { - cmd.arg("--target").arg(target); - } - - // If Cargo wants to set RUSTFLAGS, use that. - if let Ok(rustflags) = env::var("CARGO_ENCODED_RUSTFLAGS") { - if !rustflags.is_empty() { - for arg in rustflags.split('\x1f') { - cmd.arg(arg); - } - } - } - - match cmd.status() { - Ok(status) => status.success(), - Err(_) => false, - } -} - -fn rustc_minor_version() -> Option<u32> { - let rustc = cargo_env_var("RUSTC"); - let output = Command::new(rustc).arg("--version").output().ok()?; - let version = str::from_utf8(&output.stdout).ok()?; - let mut pieces = version.split('.'); - if pieces.next() != Some("rustc 1") { - return None; - } - pieces.next()?.parse().ok() -} - -fn cargo_env_var(key: &str) -> OsString { - env::var_os(key).unwrap_or_else(|| { - eprintln!( - "Environment variable ${} is not set during execution of build script", - key, - ); - process::exit(1); - }) -} |