fix: feature gates

build_helpers/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "build_helpers"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+homepage.workspace = true
+categories.workspace = true
+keywords.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+cfg_aliases = { version = "0.2.1" }
+
+[lints]
+workspace = true

build_helpers/src/lib.rs

@@ -0,0 +1,23 @@
+use cfg_aliases::cfg_aliases;
+
+pub fn cfg_aliases_setup() {
+    // The script doesn't depend on our code
+    println!("cargo:rerun-if-changed=build.rs");
+
+    // Setup cfg aliases
+    cfg_aliases! {
+        // Systems.
+        android_platform: { target_os = "android" },
+        wasm_platform: { all(target_family = "wasm", not(target_os = "emscripten")) },
+        macos_platform: { target_os = "macos" },
+        ios_platform: { target_os = "ios" },
+        windows_platform: { target_os = "windows" },
+        apple: { any(target_os = "ios", target_os = "macos") },
+        free_unix: { all(unix, not(apple), not(android_platform), not(target_os = "emscripten")) },
+        redox: { target_os = "redox" },
+
+        // Native displays.
+        wayland_platform: { all(feature = "wayland", free_unix, not(wasm), not(redox)) },
+        orbital_platform: { redox },
+    }
+}