[libcxx-commits] [libcxx] [llvm] [CI][Github] Add linux premerge workflow (PR #119635)

[Mehdi Amini via libcxx-commits]

================
@@ -0,0 +1,66 @@
+name: LLVM Premerge Checks
+
+permissions:
+  contents: read
+
+on:
+  pull_request:
+    paths:
+      - .github/workflows/premerge.yaml
+
+jobs:
+  premerge-checks-linux:
+    if: github.repository_owner == 'llvm'
+    runs-on: llvm-premerge-linux-runners
+    concurrency:
+      group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
+      cancel-in-progress: true
+    container:
+      image: ghcr.io/llvm/ci-ubuntu-22.04:latest
+    defaults:
+      run:
+        shell: bash
+    steps:
+      - name: Checkout LLVM
+        uses: actions/checkout at v4
+        with:
+          fetch-depth: 2
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action at v1.2.14
+      - name: Build and Test
+        run: |
+          git config --global --add safe.directory '*'
+
+          modified_files=$(git diff --name-only HEAD~1...HEAD)
+          modified_dirs=$(echo "$modified_files" | cut -d'/' -f1 | sort -u)
+
+          echo $modified_files
+          echo $modified_dirs
----------------
joker-eph wrote:

If you mean to leave this here for debugging, should we add better output?
Like:

```
echo "===== Modified files in the PR ====="
echo $modified_files
echo "===== Modified dirs in the PR ====="
echo $modified_dies

https://github.com/llvm/llvm-project/pull/119635