fn main() { // If building for macos and WINIT_LINK_COLORSYNC is set to true // use CGDisplayCreateUUIDFromDisplayID from ColorSync instead of CoreGraphics if std::env::var("CARGO_CFG_TARGET_OS").map_or(false, |os| os == "macos") && std::env::var("WINIT_LINK_COLORSYNC") .map_or(false, |v| v == "1" || v.eq_ignore_ascii_case("true")) { println!("cargo:rustc-cfg=use_colorsync_cgdisplaycreateuuidfromdisplayid"); } }