[llvm] [workflows] Add post-commit job that periodically runs the clang static analyzer (PR #94106)

[Aiden Grossman via llvm-commits]

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@@ -0,0 +1,69 @@
+name: Post-Commit Static Analyzer
+
+permissions:
+  contents: read
+
+on:
+  push:
+    branches:
+      - 'release/**'
+    paths:
+      - 'llvm/**'
+      - '.github/workflows/ci-post-commit-analyzer.yml'
+  pull_request:
+    paths:
+      - '.github/workflows/ci-post-commit-analyzer.yml'
+  schedule:
+    - cron: '30 0 * * *'
+
+concurrency:
+  group: >-
+    llvm-project-${{ github.workflow }}-${{ github.event_name == 'pull_request' &&
+      ( github.event.pull_request.number || github.ref) }}
+  cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
+
+jobs:
+  post-commit-analyzer:
+    if: >-
+      github.repository_owner == 'llvm' &&
+      github.event.action != 'closed'
+    runs-on: ubuntu-22.04
+    env:
+      LLVM_VERSION: 18
+    steps:
+      - name: Checkout Source
+        uses: actions/checkout at b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+
+      - name: Install Dependencies
+        run: |
+          sudo echo "deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-18 main" | sudo tee -a /etc/apt/sources.list.d/llvm.list
+          wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+          sudo apt-get update
+          sudo apt-get install \
+            cmake \
+            ninja-build \
+            perl \
+            clang-tools-$LLVM_VERSION \
+            clang-$LLVM_VERSION
+
+      - name: Configure
+        run: |
+          scan-build-$LLVM_VERSION \
+              --use-c++=clang++ \
+              --use-cc=clang \
+              cmake -B build -S llvm -G Ninja \
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boomanaiden154 wrote:

I'm guessing we could get speed-ups with PGO+ThinLTO+BOLT assuming perf-training on a good workload. That would be quite a bit of work to get going though. Might be something to look into down the road if this ends up getting used. We could split jobs like we've started doing in other places, but that would also take significant effort to implement.

I don't think I like the idea of just running until the job times out and then uploading whatever is there. I think that might make some issues pop up/go away each invocation depending upon what files it gets, decreasing the signal to noise ratio.

https://github.com/llvm/llvm-project/pull/94106