[llvm] [Github][Bazel] Add Workflow to Run Bazel Build (PR #165071)

[Aiden Grossman via llvm-commits]

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@@ -30,3 +30,28 @@ jobs:
       - name: Run Buildifier
         run: |
           buildifier --mode=check $(find ./utils/bazel -name *BUILD*)
+  
+  bazel-build:
+    name: "Bazel Build/Test"
+    runs-on: llvm-premerge-linux-runners
+    if: github.repository == 'llvm/llvm-project'
+    steps:
+      - name: Fetch LLVM sources
+        uses: actions/checkout at 08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        # TODO(boomanaiden154): We should use a purpose built container for this. Move
+        # over when we have fixed the issues with using custom containers with Github
+        # ARC in GKE.
+      - name: Setup System Dependencies
+        run: |
+          sudo apt-get update
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boomanaiden154 wrote:

Right, those would be the only two external dependencies. We also depend on the system provided standard libraries, but those will remain consistent within a single container version. I don't think this will be a large issue though as I don't think MPFR/PFM get upgraded often at all in the stable distros compared to the rate at which LLVM changes to make a big difference cache rate wise.

Making the build more hermetic might be nicer in itself though, but not sure it matters too much for what we're trying to do here.

https://github.com/llvm/llvm-project/pull/165071