Specify linker in m68k CI

Author: antoyo

.github/workflows/m68k.yml

@@ -63,8 +63,6 @@ jobs:
     - name: Set env
       run: |
         echo "workspace="$GITHUB_WORKSPACE >> $GITHUB_ENV
-        
-        
 
     #- name: Cache rust repository
       ## We only clone the rust repository for rustc tests
@@ -85,7 +83,7 @@ jobs:
       run: |
         ./y.sh prepare --only-libcore --cross
         ./y.sh build --sysroot --features compiler_builtins/no-f16-f128 --target-triple m68k-unknown-linux-gnu --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
-        ./y.sh cargo build --manifest-path=./tests/hello-world/Cargo.toml --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
+        CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc" ./y.sh cargo build --manifest-path=./tests/hello-world/Cargo.toml --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
         ./y.sh clean all
 
     - name: Build