Change working directory for Docker build

An attempt to use learnings from here:

actions/runner#1009

.github/workflows/gcc-problems.yml

@@ -1,5 +1,11 @@
 #######
 # This pipeline runs various static analysis (e.g. GCC warnings) against the c / c++ pull requests.
+#
+# TODO: Move Docker container caching / storage to a repository
+#
+# TODO: Reduce workflow description duplication across jobs
+#   - Option: by use of Workflow Templates per gcc-build-target (need to move docker build to another workflow and requires container repo)
+#   - Option: by improving our build system and enabling faster build-all-targets
 #######
 name: "GCC Warnings & Errors"
 on:
@@ -59,11 +65,14 @@ jobs:
           name: build_container
           path: /tmp/mme_builder.tar
 
-  # TODO: Output build log file as artifact (copy out of docker, cache artifact)
   build_oai:
     runs-on: ubuntu-latest
     needs: gen_build_container
     steps:
+      - 
+        # This is necessary for overlays into the Docker container below?
+        name: Check Out Repo 
+        uses: actions/checkout@v2
       -
         # I am using mmagician fork of get-changed-files (forked from jitterbit/get-changed-files)
         #   Rationale: our workflow (merge branch into upstream master) is incompatible
@@ -74,8 +83,65 @@ jobs:
         with:
           format: 'space-delimited'
       -
-        name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v1
+        name: Download docker image from generate_container_for_build
+        uses: actions/download-artifact@v2
+        with:
+          name: build_container
+          path: /tmp
+      -
+        name: Load Docker image
+        run: |
+          docker load --input /tmp/mme_builder.tar
+          docker image ls -a
+      -
+        # If needed https://github.com/microsoft/vscode-cpptools/issues/2266 for path fixups
+        #
+        # Additional GH Issues regarding paths for monorepos without root build.
+        # - https://github.com/actions/runner/issues/659
+        # - https://github.com/actions/runner/issues/765
+        #
+        # Paths emitted on warnings must be relative to the repository (e.g. lte/gateway/...),
+        # Therefore below I use `xo` to fixup our path emissions on gcc warnings.
+        uses: electronjoe/gcc-problem-matcher@v1
+      -
+        name: Build and Apply GCC Problem Matcher
+        uses: addnab/docker-run-action@v2
+        with:
+          image: magma/mme_builder:latest
+          # TODO: Remove work-around mount to /work (https://github.com/addnab/docker-run-action/issues/11)
+          options: -v ${{ github.workspace }}:/work -e ABC=123
+          run: |
+            echo "Github Workspace SHM: $GITHUB_WORKSPACE"
+            ls -R /github/
+            cd /work/lte/gateway/
+            make build_oai 2>&1 > /work/compile.log
+            for file in ${{ steps.changed_files.outputs.all }};
+            do grep $file /work/compile.log | xo '/\/magma\/((.*):(\d+):(\d+):\s+(?:fatal\s)?(warning|error):\s+(.*))/$1/' || true;
+            done;
+      -
+        name: Store build_logs_oai Artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: build_logs_oai
+          path: ${{ github.workspace }}/compile.log      
+
+  build_session_manager:
+    runs-on: ubuntu-latest
+    needs: gen_build_container
+    steps:
+      - 
+        # This is necessary for overlays into the Docker container below?
+        name: Check Out Repo 
+        uses: actions/checkout@v2
+      -
+        # I am using mmagician fork of get-changed-files (forked from jitterbit/get-changed-files)
+        #   Rationale: our workflow (merge branch into upstream master) is incompatible
+        #   See long list of GH Issues on https://github.com/jitterbit/get-changed-files w.r.t. head ahead of base
+        name: Fetch list of changed files
+        id: changed_files
+        uses: mmagician/get-changed-files@v2
+        with:
+          format: 'space-delimited'
       -
         name: Download docker image from generate_container_for_build
         uses: actions/download-artifact@v2
@@ -93,17 +159,28 @@ jobs:
         # Additional GH Issues regarding paths for monorepos without root build.
         # - https://github.com/actions/runner/issues/659
         # - https://github.com/actions/runner/issues/765
+        #
+        # Paths emitted on warnings must be relative to the repository (e.g. lte/gateway/...),
+        # Therefore below I use `xo` to fixup our path emissions on gcc warnings.
         uses: electronjoe/gcc-problem-matcher@v1
       -
         name: Build and Apply GCC Problem Matcher
         uses: addnab/docker-run-action@v2
         with:
           image: magma/mme_builder:latest
-          # TODO: Break up this long line (can I use '\' at end of each line?)
-          run: cd /magma/lte/gateway;make build_oai 2>&1 > /compile.log;for file in ${{ steps.changed_files.outputs.all }}; do grep $file /compile.log | xo '/\/magma\/((.*):(\d+):(\d+):\s+(?:fatal\s)?(warning|error):\s+(.*))/$1/' || true; done;
+          # TODO: Remove work-around mount to /work (https://github.com/addnab/docker-run-action/issues/11)
+          options: -v ${{ github.workspace }}:/work -e ABC=123
+          run: |
+            echo "Github Workspace SHM: $GITHUB_WORKSPACE"
+            ls -R /github/
+            cd /work/lte/gateway/
+            make build_session_manager 2>&1 > /work/compile.log
+            for file in ${{ steps.changed_files.outputs.all }};
+            do grep $file /work/compile.log | xo '/\/magma\/((.*):(\d+):(\d+):\s+(?:fatal\s)?(warning|error):\s+(.*))/$1/' || true;
+            done;
       -
-        name: Store oai_build_logs artifact
+        name: Store build_logs_session_manager Artifact
         uses: actions/upload-artifact@v2
         with:
-          name: oai_build_logs
-          path: /compile.log      
+          name: build_logs_session_manager
+          path: ${{ github.workspace }}/compile.log      

lte/gateway/c/session_manager/AAAClient.cpp

@@ -22,6 +22,7 @@ namespace {  // anonymous
 
 aaa::terminate_session_request create_deactivate_req(
     const std::string& radius_session_id, const std::string& imsi) {
+  int yet_another_unused_variable = 2;
   aaa::terminate_session_request req;
   req.set_radius_session_id(radius_session_id);
   req.set_imsi(imsi);