Merge pull request #160 from rcore-os/examples

Tidy up aarch64 example build

examples/aarch64/build.rs

@@ -1,29 +1,29 @@
 use cc::Build;
 use std::env;
 
+const PLATFORMS: [&str; 2] = ["crosvm", "qemu"];
+
 fn main() {
-    env::set_var("CROSS_COMPILE", "aarch64-linux-gnu");
+    println!(
+        "cargo::rustc-check-cfg=cfg(platform, values(\"{}\"))",
+        PLATFORMS.join("\", \"")
+    );
+
+    env::set_var("CROSS_COMPILE", "aarch64-none-elf");
+    env::set_var("CC", "clang");
+
     let platform = env::var("CARGO_CFG_PLATFORM").expect("Missing platform name");
-    match platform.as_ref() {
-        "qemu" => {
-            Build::new()
-                .file("entry.S")
-                .file("exceptions.S")
-                .file("idmap.S")
-                .compile("empty");
-            println!("cargo:rustc-link-arg=-Tqemu.ld");
-        }
-        "crosvm" => {
-            Build::new()
-                .file("entry.S")
-                .file("exceptions.S")
-                .file("idmap_crosvm.S")
-                .compile("empty");
-            println!("cargo:rustc-link-arg=-Tcrosvm.ld");
-        }
-        _ => {
-            panic!("Unexpected platform name \"{}\"", platform);
-        }
-    }
+    assert!(
+        PLATFORMS.contains(&platform.as_str()),
+        "Unexpected platform name {:?}. Supported platforms: {:?}",
+        platform,
+        PLATFORMS,
+    );
+    Build::new()
+        .file("entry.S")
+        .file("exceptions.S")
+        .file(format!("idmap_{platform}.S"))
+        .compile("example");
+    println!("cargo:rustc-link-arg=-T{platform}.ld");
     println!("cargo:rustc-link-arg=-Timage.ld");
 }