Manually run in a VM in the m68k CI

Author: antoyo

.github/workflows/m68k.yml

@@ -108,10 +108,12 @@ jobs:
       run: |
         ./y.sh build --target-triple m68k-unknown-linux-gnu
 
+        vm_dir=$(pwd)/vm
         cd tests/hello-world
         CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc" ../../y.sh cargo build --target m68k-unknown-linux-gnu
-        CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc" ../../y.sh cargo run --target m68k-unknown-linux-gnu > hello_world_stdout
-        test $(cat hello_world_stdout) == "Hello, world!" || exit 1
+        sudo cp target/m68k-unknown-linux-gnu/debug/hello_world $vm_dir/home/
+        sudo chroot $vm_dir qemu-m68k-static /home/hello_world > hello_world_stdout
+        test $(cat hello_world_stdout) == "Hello, world!" || (echo "Output differs. Actual output: $(cat hello_world_stdout)"; exit 1)
 
   # Summary job for the merge queue.
   # ALL THE PREVIOUS JOBS NEED TO BE ADDED TO THE `needs` SECTION OF THIS JOB!

build_system/src/config.rs

@@ -374,6 +374,7 @@ impl ConfigInfo {
             if self.target_triple.is_empty() {
                 return Err("Unknown non-native platform".to_string());
             }
+            // TODO: check if this is still needed.
             linker = Some(format!("-Clinker={}-gcc", self.target_triple));
             self.run_in_vm = true;
         }