gh-112301: Enable warning emitting options and ignore warnings in CI (#123020)

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>

.github/workflows/reusable-macos.yml

@@ -35,7 +35,7 @@ jobs:
         path: config.cache
         key: ${{ github.job }}-${{ inputs.os }}-${{ env.IMAGE_VERSION }}-${{ inputs.config_hash }}
     - name: Install Homebrew dependencies
-      run: brew install pkg-config openssl@3.0 xz gdbm tcl-tk
+      run: brew install pkg-config openssl@3.0 xz gdbm tcl-tk make
     - name: Configure CPython
       run: |
         GDBM_CFLAGS="-I$(brew --prefix gdbm)/include" \
@@ -48,10 +48,22 @@ jobs:
           --prefix=/opt/python-dev \
           --with-openssl="$(brew --prefix openssl@3.0)"
     - name: Build CPython
-      run: set -o pipefail; make -j8 2>&1 | tee compiler_output.txt
+      if : ${{ inputs.free-threading || inputs.os != 'macos-13' }}
+      run: gmake -j8
+    - name: Build CPython for compiler warning check
+      if : ${{ !inputs.free-threading && inputs.os == 'macos-13' }}
+      run: set -o pipefail; gmake -j8 --output-sync 2>&1 | tee compiler_output_macos.txt
     - name: Display build info
       run: make pythoninfo
     - name: Check compiler warnings
-      run: python3 Tools/build/check_warnings.py --compiler-output-file-path=compiler_output.txt --warning-ignore-file-path=Tools/build/.warningignore_macos --compiler-output-type=clang
+      if : ${{ !inputs.free-threading && inputs.os == 'macos-13' }}
+      run: >-
+        python3 Tools/build/check_warnings.py
+        --compiler-output-file-path=compiler_output_macos.txt
+        --warning-ignore-file-path=Tools/build/.warningignore_macos
+        --compiler-output-type=clang
+        --fail-on-regression
+        --fail-on-improvement
+        --path-prefix="./"
     - name: Tests
       run: make test

.github/workflows/reusable-ubuntu.yml

@@ -67,20 +67,32 @@ jobs:
       working-directory: ${{ env.CPYTHON_BUILDDIR }}
       run: >-
         ../cpython-ro-srcdir/configure
-        CFLAGS="-fdiagnostics-format=json"
         --config-cache
         --with-pydebug
         --enable-slower-safety
         --with-openssl=$OPENSSL_DIR
         ${{ fromJSON(inputs.free-threading) && '--disable-gil' || '' }}
     - name: Build CPython out-of-tree
+      if: ${{ inputs.free-threading }}
       working-directory: ${{ env.CPYTHON_BUILDDIR }}
-      run: set -o pipefail; make -j4 2>&1 | tee compiler_output.txt
+      run: make -j4
+    - name: Build CPython out-of-tree (for compiler warning check)
+      if: ${{ !inputs.free-threading}}
+      working-directory: ${{ env.CPYTHON_BUILDDIR }}
+      run: set -o pipefail; make -j4 2>&1 | tee compiler_output_ubuntu.txt
     - name: Display build info
       working-directory: ${{ env.CPYTHON_BUILDDIR }}
       run: make pythoninfo
     - name: Check compiler warnings
-      run: python Tools/build/check_warnings.py --compiler-output-file-path=${{ env.CPYTHON_BUILDDIR }}/compiler_output.txt --warning-ignore-file-path ${GITHUB_WORKSPACE}/Tools/build/.warningignore_ubuntu --compiler-output-type=json
+      if: ${{ !inputs.free-threading }}
+      run: >-
+        python Tools/build/check_warnings.py
+        --compiler-output-file-path=${{ env.CPYTHON_BUILDDIR }}/compiler_output_ubuntu.txt
+        --warning-ignore-file-path ${GITHUB_WORKSPACE}/Tools/build/.warningignore_ubuntu
+        --compiler-output-type=gcc
+        --fail-on-regression
+        --fail-on-improvement
+        --path-prefix="../cpython-ro-srcdir/"
     - name: Remount sources writable for tests
       # some tests write to srcdir, lack of pyc files slows down testing
       run: sudo mount $CPYTHON_RO_SRCDIR -oremount,rw