build all code with all available C++ standards in CI

Author: firewave

.github/workflows/CI-unixish.yml

@@ -71,15 +71,26 @@ jobs:
       run: |
         make -j$(nproc) selfcheck
 
-    - name: make testrunner (c++17)
+    - name: make (c++14)
       run: |
         make clean
-        make -j$(nproc) testrunner CXXOPTS="-std=c++17"
+        make -j$(nproc) CXXOPTS="-Werror -std=c++14"
 
-    - name: make testrunner (c++20)
+    - name: make (c++17)
       run: |
         make clean
-        make -j$(nproc) testrunner CXXOPTS="-std=c++20"
+        make -j$(nproc) CXXOPTS="-Werror -std=c++17"
+
+    - name: make (c++20)
+      run: |
+        make clean
+        make -j$(nproc) CXXOPTS="-Werror -std=c++20"
+
+    - name: make (c++23)
+      run: |
+        make clean
+        # ubuntu-22.04 and macos-14 do not support c++23 yet
+        make -j$(nproc) CXXOPTS="-Werror -std=c++2b"
 
     - name: Run CMake
       run: |

.github/workflows/CI-windows.yml

@@ -63,4 +63,20 @@ jobs:
         run: |
           set SIMPLECPP_EXE_PATH=.\${{ matrix.config }}\simplecpp.exe
           python -m pytest integration_test.py -vv || exit /b !errorlevel!
-        
+
+      - name: Run CMake (c++17)
+        run: |
+          cmake -S . -B build.cxx17 -G "Visual Studio 17 2022" -A x64 -Werror=dev --warn-uninitialized -DCMAKE_CXX_STANDARD=20 -DCMAKE_COMPILE_WARNING_AS_ERROR=On || exit /b !errorlevel!
+
+      - name: Build (c++17)
+        run: |
+          msbuild -m build.cxx17\simplecpp.sln /p:Configuration=${{ matrix.config }} /p:Platform=x64 || exit /b !errorlevel!
+
+      - name: Run CMake (c++20)
+        run: |
+          cmake -S . -B build.cxx20 -G "Visual Studio 17 2022" -A x64 -Werror=dev --warn-uninitialized -DCMAKE_CXX_STANDARD=20 -DCMAKE_COMPILE_WARNING_AS_ERROR=On || exit /b !errorlevel!
+
+      - name: Build (c++20)
+        run: |
+          msbuild -m build.cxx20\simplecpp.sln /p:Configuration=${{ matrix.config }} /p:Platform=x64 || exit /b !errorlevel!
+