CI: add ubuntu/gcc12/mpich job using only external dependencies

Author: vicentebolea

.github/workflows/everything.yml

@@ -211,6 +211,66 @@ jobs:
         if: ${{ matrix.constrains != 'build_only' }}
         run: gha/scripts/ci/gh-actions/run.sh test
 
+  ubuntu_ext:
+    needs: [format, git_checks]
+    if: needs.git_checks.outputs.num_code_changes > 0
+
+    runs-on: ubuntu-22.04
+    permissions:
+      contents: read
+      actions: write  # for cache save
+    container:
+      image: ghcr.io/ornladios/adios2:ci-spack-ubuntu22.04-gcc12
+      options: --shm-size=1g
+      env:
+        GH_YML_JOBNAME: ubuntu22.04-gcc12-ext-mpich
+        GH_YML_BASE_OS: Linux
+        GH_YML_MATRIX_OS: ubuntu22.04
+        GH_YML_MATRIX_COMPILER: gcc12
+        GH_YML_MATRIX_PARALLEL: mpich
+        CCACHE_BASEDIR: "${GITHUB_WORKSPACE}"
+        CCACHE_DIR: "${GITHUB_WORKSPACE}/.ccache"
+        CCACHE_COMPRESS: true
+        CCACHE_COMPRESSLEVEL: 6
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
+        with:
+          path: gha
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+          path: source
+      - name: Restore cache
+        uses: actions/cache/restore@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v4
+        id: restore-cache
+        with:
+          path: .ccache
+          key: ccache-ubuntu22.04-gcc12-ext-mpich-${{ github.sha }}
+          restore-keys: |
+            ccache-ubuntu22.04-gcc12-ext-mpich
+      - name: Configure cache
+        run: ccache -z
+      - name: Setup
+        run: gha/scripts/ci/gh-actions/linux-setup.sh
+      - name: Update
+        run: gha/scripts/ci/gh-actions/run.sh update
+      - name: Configure
+        run: gha/scripts/ci/gh-actions/run.sh configure
+      - name: Build
+        run: gha/scripts/ci/gh-actions/run.sh build
+      - name: Print ccache statistics
+        run: ccache -s | tee $GITHUB_STEP_SUMMARY
+      - name: Save cache
+        uses: actions/cache/save@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v4
+        if: ${{ github.ref_name == 'master' && steps.restore-cache.outputs.cache-hit != 'true' }}
+        id: save-cache
+        with:
+          path: .ccache
+          key: ccache-ubuntu22.04-gcc12-ext-mpich-${{ github.sha }}
+      - name: Test
+        run: gha/scripts/ci/gh-actions/run.sh test
+
   el8:
     needs: [format, git_checks]
     if: needs.git_checks.outputs.num_code_changes > 0
@@ -632,7 +692,7 @@ jobs:
 #######################################
 
   build_and_test:
-    needs: [el8, ubuntu, macos, windows, docker, contract]
+    needs: [el8, ubuntu, ubuntu_ext, macos, windows, docker, contract]
     runs-on: ubuntu-latest
     steps:
       - run: echo "All required jobs complete"

scripts/ci/cmake/ci-ubuntu22.04-gcc12-ext-mpich.cmake

@@ -0,0 +1,59 @@
+# SPDX-FileCopyrightText: 2026 Oak Ridge National Laboratory and Contributors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+include(ProcessorCount)
+ProcessorCount(NCPUS)
+math(EXPR N2CPUS "${NCPUS}*2")
+
+set(ENV{CC}  gcc)
+set(ENV{CXX} g++)
+set(ENV{FC}  gfortran)
+
+execute_process(
+  COMMAND "python3-config" "--prefix"
+  OUTPUT_VARIABLE PY_ROOT
+  OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+set(dashboard_cache "
+BUILD_TESTING:BOOL=ON
+ADIOS2_BUILD_EXAMPLES:BOOL=ON
+
+ADIOS2_USE_BZip2:BOOL=ON
+ADIOS2_USE_Blosc2:BOOL=ON
+ADIOS2_USE_DataMan:BOOL=ON
+ADIOS2_USE_Fortran:BOOL=ON
+ADIOS2_USE_HDF5:BOOL=ON
+ADIOS2_USE_MPI:BOOL=ON
+ADIOS2_USE_Python:BOOL=ON
+ADIOS2_USE_SZ:BOOL=ON
+ADIOS2_USE_ZeroMQ:STRING=ON
+ADIOS2_USE_ZFP:BOOL=ON
+
+ADIOS2_USE_EXTERNAL_DEPENDENCIES:BOOL=ON
+ADIOS2_USE_EXTERNAL_EVPATH:BOOL=ON
+
+Python_ROOT_DIR:PATH=${PY_ROOT}
+Python_FIND_STRATEGY:STRING=LOCATION
+Python_FIND_FRAMEWORK:STRING=FIRST
+
+CMAKE_C_COMPILER_LAUNCHER=ccache
+CMAKE_CXX_COMPILER_LAUNCHER=ccache
+CMAKE_C_FLAGS:STRING=-Wall
+CMAKE_CXX_FLAGS:STRING=-Wall
+CMAKE_Fortran_FLAGS:STRING=-Wall
+
+OpenMP_gomp_LIBRARY:FILEPATH=/spack/var/spack/environments/adios2-ci-mpich/.spack-env/view/lib/libgomp.so.1
+
+MPIEXEC_MAX_NUMPROCS:STRING=${N2CPUS}
+")
+
+# We have a dedicated build for gcc8 + serial, so we exclude ".Serial$"
+# TODO: The Kill* and PreciousTimeStep tests fail (due to timeout) when
+# TODO: adios2 is built "--with-device=ch3:sock:tcp".  Once this is fixed
+# TODO:  in the mpi_dp, we can re-enable these tests.
+set(CTEST_TEST_ARGS EXCLUDE "KillReader|KillWriter|PreciousTimestep|.Serial$")
+
+set(CTEST_CMAKE_GENERATOR "Ninja")
+list(APPEND CTEST_UPDATE_NOTES_FILES "${CMAKE_CURRENT_LIST_FILE}")
+include(${CMAKE_CURRENT_LIST_DIR}/ci-common.cmake)