[3.15] gh-152785: Upgrade Ubuntu from 24.04 to 26.04 in GitHub Actions (#152717) (#153416)

gh-152785: Upgrade Ubuntu from 24.04 to 26.04 in GitHub Actions (#152717)

* Replace "ubuntu-24.04" with "ubuntu-26.04".
* Replace "ubuntu-latest" with "ubuntu-26.04" for Cross build Linux.
* Replace "ubuntu-latest" with "ubuntu-slim" for small workloads.
* Update ".github/actionlint.yaml" to allow "ubuntu-26.04"
  and "ubuntu-26.04-arm" images.
* Install Ubuntu libmpdec-dev package, rather than installing libmpdec
  from source (tarball).

Backport changes:

* Keep https://apt.llvm.org/llvm.sh to install LLVM 19 and LLVM 20.
* WASI uses ubuntu-26.04, not ubuntu-26.04-arm.

(cherry picked from commit 4c79929)

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
(cherry picked from commit da999e6)

Author: vstinner

.github/actionlint.yaml

@@ -1,5 +1,12 @@
 config-variables: null
 
+# Pending release of actionlint > 1.7.12 for ubuntu-26.04* support:
+# https://github.com/rhysd/actionlint/pull/683
+self-hosted-runner:
+  labels:
+    - ubuntu-26.04
+    - ubuntu-26.04-arm
+
 paths:
   .github/workflows/**/*.yml:
      ignore:

.github/workflows/add-issue-header.yml

@@ -17,7 +17,7 @@ permissions:
 
 jobs:
   add-header:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     permissions:
       issues: write
     timeout-minutes: 5

.github/workflows/build.yml

@@ -100,7 +100,7 @@ jobs:
     name: 'Check if Autoconf files are up to date'
     # Don't use ubuntu-latest but a specific version to make the job
     # reproducible: to get the same tools versions (autoconf, aclocal, ...)
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     container:
       image: ghcr.io/python/autoconf:2025.01.02.12581854023
     timeout-minutes: 60
@@ -143,7 +143,7 @@ jobs:
     name: 'Check if generated files are up to date'
     # Don't use ubuntu-latest but a specific version to make the job
     # reproducible: to get the same tools versions (autoconf, aclocal, ...)
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     needs: build-context
     if: needs.build-context.outputs.run-tests == 'true'
@@ -273,14 +273,14 @@ jobs:
         - false
         - true
         os:
-        - ubuntu-24.04
-        - ubuntu-24.04-arm
+        - ubuntu-26.04
+        - ubuntu-26.04-arm
         exclude:
         # Do not test BOLT with free-threading, to conserve resources
         - bolt: true
           free-threading: true
         # BOLT currently crashes during instrumentation on aarch64
-        - os: ubuntu-24.04-arm
+        - os: ubuntu-26.04-arm
           bolt: true
     uses: ./.github/workflows/reusable-ubuntu.yml
     with:
@@ -297,7 +297,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-24.04]
+        os: [ubuntu-26.04]
         ssllib:
           # See Tools/ssl/make_ssl_data.py for notes on adding a new version
           ## OpenSSL
@@ -370,7 +370,7 @@ jobs:
           - arch: aarch64
             runs-on: macos-26
           - arch: x86_64
-            runs-on: ubuntu-24.04
+            runs-on: ubuntu-26.04
 
     runs-on: ${{ matrix.runs-on }}
     steps:
@@ -417,7 +417,7 @@ jobs:
 
   test-hypothesis:
     name: "Hypothesis tests on Ubuntu"
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     needs: build-context
     if: needs.build-context.outputs.run-ubuntu == 'true'
@@ -528,7 +528,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-24.04]
+        os: [ubuntu-26.04]
     env:
       OPENSSL_VER: 3.5.7
       PYTHONSTRICTEXTENSIONBUILD: 1
@@ -592,7 +592,7 @@ jobs:
 
   cross-build-linux:
     name: Cross build Linux
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     needs: build-context
     if: needs.build-context.outputs.run-ubuntu == 'true'

.github/workflows/jit.yml

@@ -26,7 +26,7 @@ env:
 jobs:
   interpreter:
     name: Interpreter (Debug)
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
@@ -139,9 +139,9 @@ jobs:
           - false
         include:
           - target: x86_64-unknown-linux-gnu/gcc
-            runner: ubuntu-24.04
+            runner: ubuntu-26.04
           - target: aarch64-unknown-linux-gnu/gcc
-            runner: ubuntu-24.04-arm
+            runner: ubuntu-26.04-arm
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
@@ -151,8 +151,7 @@ jobs:
           python-version: '3.11'
       - name: Build
         run: |
-          sudo bash -c "$(wget -O - https://apt.llvm.org/llvm.sh)" ./llvm.sh ${{ env.LLVM_VERSION }}
-          export PATH="$(llvm-config-${{ env.LLVM_VERSION }} --bindir):$PATH"
+          # On ubuntu-26.04 image, clang is clang-21 by default
           ./configure --enable-experimental-jit ${{ matrix.debug && '--with-pydebug' || '' }}
           make all --jobs 4
       - name: Test
@@ -162,7 +161,7 @@ jobs:
   linux-extras:
     name: ${{ matrix.name }}
 
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     strategy:
       fail-fast: false
@@ -185,8 +184,7 @@ jobs:
           python-version: '3.11'
       - name: Build
         run: |
-          sudo bash -c "$(wget -O - https://apt.llvm.org/llvm.sh)" ./llvm.sh ${{ env.LLVM_VERSION }}
-          export PATH="$(llvm-config-${{ env.LLVM_VERSION }} --bindir):$PATH"
+          # On ubuntu-26.04 image, clang is clang-21 by default
           if [ "${{ matrix.use_clang }}" = "true" ]; then
             export CC=clang-${{ env.LLVM_VERSION }}
           fi

.github/workflows/new-bugs-announce-notifier.yml

@@ -10,7 +10,7 @@ permissions:
 
 jobs:
   notify-new-bugs-announce:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     permissions:
       issues: read
     timeout-minutes: 10

.github/workflows/posix-deps-apt.sh

@@ -4,21 +4,21 @@ apt-get update
 apt-get -yq --no-install-recommends install \
     build-essential \
     pkg-config \
+    curl \
     gdb \
     lcov \
     libb2-dev \
     libbz2-dev \
     libffi-dev \
-    libgdbm-dev \
     libgdbm-compat-dev \
+    libgdbm-dev \
     liblzma-dev \
+    libmpdec-dev \
     libncurses5-dev \
     libreadline6-dev \
     libsqlite3-dev \
     libssl-dev \
     libzstd-dev \
-    lzma \
-    lzma-dev \
     strace \
     tk-dev \
     uuid-dev \

.github/workflows/require-pr-label.yml

@@ -11,7 +11,7 @@ jobs:
   label-dnm:
     name: DO-NOT-MERGE
     if: github.repository_owner == 'python'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     permissions:
       pull-requests: read
     timeout-minutes: 10
@@ -28,7 +28,7 @@ jobs:
   label-reviews:
     name: Unresolved review
     if: github.repository_owner == 'python'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     permissions:
       pull-requests: read
     timeout-minutes: 10

.github/workflows/reusable-docs.yml

@@ -90,7 +90,7 @@ jobs:
   # Run "doctest" on HEAD as new syntax doesn't exist in the latest stable release
   doctest:
     name: 'Doctest'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     steps:
     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2

.github/workflows/reusable-emscripten.yml

@@ -12,7 +12,7 @@ env:
 jobs:
   build-emscripten-reusable:
     name: 'build and test'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 40
     steps:
     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2

.github/workflows/reusable-san.yml

@@ -27,7 +27,7 @@ jobs:
         && ' (free-threading)'
         || ''
       }}
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     steps:
     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2