Pull out llvm version

.github/workflows/rust.yaml

@@ -26,19 +26,26 @@ on:
 
 name: Workflow checks for rust code
 
+env:
+  LLVM_VERSION : "17.0"
+
 jobs:
   test:
     runs-on: ubuntu-latest
     strategy:
       matrix:
         test-code:
           - "cd bril-rs && make test TURNTARGS=-v"
-          - "cd bril-rs && make features"
           - "cd brilirs && make test TURNTARGS=-v"
           - "cd brilirs && make benchmark TURNTARGS=-v"
           - "cd brilift && cargo build --release && make rt.o && make test TURNTARGS=-v"
           - "cd brilift && cargo build --release && make rt.o && make benchmark TURNTARGS=-v"
-          - "cd bril-rs/brillvm && make rt"
+        # Code requiring additional dependencies are separated out
+        include:
+          - test-code: "cd bril-rs && make features"
+            needs_cargo_hack: true
+          - test-code: "cd bril-rs/brillvm && make rt"
+            needs_llvm: true
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@v1
@@ -47,13 +54,13 @@ jobs:
 
       - name: Install LLVM and Clang
         uses: KyleMayes/install-llvm-action@v1
-        if: matrix.test-code == 'cd bril-rs/brillvm && make rt'
+        if: matrix.needs_llvm
         with:
-          version: "17.0"
+          version: ${{ env.LLVM_VERSION }}
 
       - name: Install cargo-hack for feature-flag checking
         run: cargo install cargo-hack
-        if: matrix.test-code == 'cd bril-rs && make features'
+        if: matrix.needs_cargo_hack
 
       - uses: actions/setup-python@v4
         with:
@@ -99,7 +106,7 @@ jobs:
         uses: KyleMayes/install-llvm-action@v1
         if: matrix.path == 'bril-rs/brillvm/Cargo.toml'
         with:
-          version: "17.0"
+          version: ${{ env.LLVM_VERSION }}
 
       - name: cargo check
         run: cargo check --manifest-path ${{ matrix.path }} --all-targets