use rustc_version::{version_meta, Channel};
fn has_cfg(name: &str) -> bool {
std::env::var_os(format!("CARGO_CFG_{}", name.to_uppercase())).is_some()
}
fn cfg(name: &str) -> String {
std::env::var(format!("CARGO_CFG_{}", name.to_uppercase())).unwrap_or_default()
}
fn main() {
println!("cargo::rerun-if-env-changed=MIRIFLAGS");
let is_miri = has_cfg("miri");
let is_tree_borrows =
std::env::var("MIRIFLAGS").is_ok_and(|flags| flags.contains("-Zmiri-tree-borrows"));
if is_miri && !is_tree_borrows {
println!("cargo::rustc-cfg=feature=\"sound-under-stacked-borrows\"");
}
println!("cargo::rerun-if-env-changed=LITHIUM_BACKEND");
if let Ok(backend) = std::env::var("LITHIUM_BACKEND") {
println!("cargo::rustc-cfg=backend=\"{backend}\"");
} else if version_meta().unwrap().channel == Channel::Nightly
&& (has_cfg("unix") || (has_cfg("windows") && cfg("target_env") == "gnu"))
&& cfg("target_os") != "emscripten"
{
println!("cargo::rustc-cfg=backend=\"itanium\"");
} else if version_meta().unwrap().channel == Channel::Nightly
&& (has_cfg("windows") && cfg("target_env") == "msvc")
&& !is_miri
{
println!("cargo::rustc-cfg=backend=\"seh\"");
} else {
println!("cargo::rustc-cfg=backend=\"panic\"");
}
}