github: Skip clang-analyze when reference generation fails.

Compiling the OVS reference is supposed to succeed unless some external
change breaks this compilation.

One example is when DPDK API changes and breaks OVS compilation.
This case is hit in the dpdk-latest branch, but also when bumping DPDK
version in the main branch.

On the other hand, the clang-analyze check goal is to validate OVS
changes, not external changes.

Fixes: d662eee ("ci: Add clang-analyze to GitHub actions.")
Signed-off-by: David Marchand <[email protected]>

.github/workflows/build-and-test.yml

@@ -336,7 +336,7 @@ jobs:
         name: logs-linux-${{ join(matrix.*, '-') }}
         path: logs.tgz
 
-  build-clang-analyze:
+  build-clang-analyze-reference:
     needs: build-dpdk
     env:
       dependencies: |
@@ -345,7 +345,9 @@ jobs:
       CC:   clang
       DPDK: dpdk
       CLANG_ANALYZE: true
-    name: clang-analyze
+    name: clang-analyze-reference
+    outputs:
+      clang_cache_key: ${{ steps.clang_cache_key.outputs.key }}
     runs-on: ubuntu-24.04
     timeout-minutes: 30
 
@@ -401,7 +403,7 @@ jobs:
         echo "$HOME/.local/bin" >> $GITHUB_PATH
 
     - name: generate cache key
-      id: cache_key
+      id: clang_cache_key
       run: |
         ver=$(${CC} -v 2>&1 | grep ' version ' | \
               sed 's/.*version \([0-9]*\.[0-9]*\.[0-9]*\).*/\1/g')
@@ -413,38 +415,87 @@ jobs:
       uses: actions/cache@v4
       with:
         path: base-clang-analyzer-results
-        key:  ${{ steps.cache_key.outputs.key }}
+        key:  ${{ steps.clang_cache_key.outputs.key }}
 
     - name: set up python
+      if: steps.clang_cache.outputs.cache-hit != 'true'
       uses: actions/setup-python@v5
       with:
         python-version: ${{ env.python_default }}
 
     - name: get cached dpdk-dir
-      uses: actions/cache/restore@v4
+      if: steps.clang_cache.outputs.cache-hit != 'true'
+      uses: actions/cache@v4
       with:
         path: dpdk-dir
         key:  ${{ needs.build-dpdk.outputs.dpdk_key }}
 
     - name: update APT cache
+      if: steps.clang_cache.outputs.cache-hit != 'true'
       run:  sudo apt update || true
 
     - name: install common dependencies
+      if: steps.clang_cache.outputs.cache-hit != 'true'
       run:  sudo apt install -y ${{ env.dependencies }}
 
     - name: prepare
+      if: steps.clang_cache.outputs.cache-hit != 'true'
       run:  ./.ci/linux-prepare.sh
 
     - name: build base reference
       if: steps.clang_cache.outputs.cache-hit != 'true'
       run:  ./.ci/linux-build.sh
 
-    - name: save cache
-      uses: actions/cache/save@v4
-      if: steps.clang_cache.outputs.cache-hit != 'true'
+  build-clang-analyze:
+    needs: [build-dpdk, build-clang-analyze-reference]
+    if: needs.build-clang-analyze-reference.result == 'success'
+    env:
+      dependencies: |
+        automake bc clang-tools libnuma-dev libunbound-dev libunwind-dev \
+        libssl-dev libtool libxdp-dev llvm-dev
+      CC:   clang
+      DPDK: dpdk
+      CLANG_ANALYZE: true
+    name: clang-analyze
+    runs-on: ubuntu-24.04
+    timeout-minutes: 30
+
+    steps:
+    - name: checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+
+    - name: update PATH
+      run: |
+        echo "$HOME/bin"        >> $GITHUB_PATH
+        echo "$HOME/.local/bin" >> $GITHUB_PATH
+
+    - name: check for analyzer result cache
+      uses: actions/cache@v4
       with:
         path: base-clang-analyzer-results
-        key:  ${{ steps.cache_key.outputs.key }}
+        key:  ${{ needs.build-clang-analyze-reference.outputs.clang_cache_key }}
+
+    - name: set up python
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{ env.python_default }}
+
+    - name: get cached dpdk-dir
+      uses: actions/cache@v4
+      with:
+        path: dpdk-dir
+        key:  ${{ needs.build-dpdk.outputs.dpdk_key }}
+
+    - name: update APT cache
+      run:  sudo apt update || true
+
+    - name: install common dependencies
+      run:  sudo apt install -y ${{ env.dependencies }}
+
+    - name: prepare
+      run:  ./.ci/linux-prepare.sh
 
     - name: build
       run:  ./.ci/linux-build.sh