[llvm] [libc++] Move test tools CI job back to k8s runner sets (PR #226564)

[Louis Dionne via llvm-commits]

https://github.com/ldionne created https://github.com/llvm/llvm-project/pull/226564

While the issue with k8s runners in #226230 is still not resolved, it is better to target the k8s runners and get transient failures than to target the old runners and have the jobs hang forever (there seems to be no runners registered in llvm-premerge-libcxx-runners).

>From 1b7f72caa141d09d81a817f9924f802fb5ea6b8c Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Fri, 25 Sep 2026 11:51:33 -0400
Subject: [PATCH] [libc++] Move test tools CI job back to k8s runner sets

While the issue with k8s runners in #226230 is still not resolved,
it is better to target the k8s runners and get transient failures than
to target the old runners and have the jobs hang forever (there seems
to be no runners registered in llvm-premerge-libcxx-runners).
---
 .github/workflows/libcxx-pr-benchmark.yml  | 1 -
 .github/workflows/libcxx-pr-test-tools.yml | 7 +++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/libcxx-pr-benchmark.yml b/.github/workflows/libcxx-pr-benchmark.yml
index 39cab7b72c5cce..2cc9ace713f276 100644
--- a/.github/workflows/libcxx-pr-benchmark.yml
+++ b/.github/workflows/libcxx-pr-benchmark.yml
@@ -123,7 +123,6 @@ jobs:
           persist-credentials: false
           ref: ${{ needs.extract-info.outputs.pr_head }}
           fetch-depth: 0
-          fetch-tags: true # This job requires access to all the Git branches so it can diff against (usually) main
 
       # This workflow is always taken from the default branch. Check out the tooling from the corresponding
       # commit so that we're always running tooling that's in sync with the workflow's definition. Only the
diff --git a/.github/workflows/libcxx-pr-test-tools.yml b/.github/workflows/libcxx-pr-test-tools.yml
index 64bbc705e5e097..9722183a542916 100644
--- a/.github/workflows/libcxx-pr-test-tools.yml
+++ b/.github/workflows/libcxx-pr-test-tools.yml
@@ -31,7 +31,9 @@ concurrency:
 jobs:
   test-tools:
     if: github.repository_owner == 'llvm'
-    runs-on: llvm-premerge-libcxx-runners
+    runs-on: llvm-premerge-linux-32-runners
+    container:
+      image: ghcr.io/llvm/libcxx-linux-builder:d79f222aea61926e7c81fa8908b12f52ea70111f
     env:
       CC: clang-23
       CXX: clang++-23
@@ -40,15 +42,16 @@ jobs:
         with:
           persist-credentials: false
           fetch-depth: 0 # some tools need full git history
-          fetch-tags: true
 
       - name: Set up Python dependencies
+        shell: bash
         run: |
           python3 -m venv .venv
           source .venv/bin/activate
           pip install -r libcxx/utils/requirements.txt
 
       - name: Run the tooling smoke test
+        shell: bash
         run: |
           source .venv/bin/activate
           libcxx/utils/ci/run-buildbot test-tools