Re-enable builds and tests on Windows

.github/workflows/build-cppfront.yaml

@@ -19,17 +19,15 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  # Comment out the Windows build until it is fixed
-  # build-windows:
-  #   runs-on: windows-latest
-  #   steps:
-  #     - uses: actions/checkout@v4
-  #     - uses: ilammy/msvc-dev-cmd@v1
-  #     - name: Compiler name & version
-  #       run: cl.exe
-  #     - name: Build
-  #       run: cl.exe source/cppfront.cpp -std:c++latest -MD -EHsc -W4 -WX
-
+  build-windows:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ilammy/msvc-dev-cmd@v1
+      - name: Compiler name & version
+        run: cl.exe
+      - name: Build
+        run: cl.exe source/cppfront.cpp -std:c++latest -MD -EHsc -W4 -WX
   build-unix-like:
     strategy:
       fail-fast: false

.github/workflows/regression-tests.yaml

@@ -59,50 +59,43 @@ jobs:
             compiler: clang++
             cxx_std: c++2b
             stdlib: default
-          # Comment out Windows tests until build on Windows is fixed
-          # - os: windows-2025
-          #   shortosname: win-25
-          #   compiler: cl.exe
-          #   cxx_std: c++latest
-          #   stdlib: default
-          # - os: windows-2025
-          #   shortosname: win-25
-          #   compiler: cl.exe
-          #   cxx_std: c++20
-          #   stdlib: default
+          - os: windows-2025
+            shortosname: win-25
+            compiler: cl.exe
+            cxx_std: c++latest
+            stdlib: default
+            vs_version: '18' # VS 2026
+          - os: windows-2025
+            shortosname: win-25
+            compiler: cl.exe
+            cxx_std: c++20
+            stdlib: default
+            vs_version: '18' # VS 2026
     steps:
     - name: Checkout repo
-      uses: actions/checkout@v4
+      uses: actions/checkout@v7
 
-    - name: Prepare compilers - macOS
-      if: matrix.os == 'macos-13'
+    - name: Prepare compiler - Clang 19
+      if: matrix.os == 'ubuntu-24.04' && startsWith(matrix.compiler, 'clang')
       run: |
-        sudo xcode-select --switch /Applications/Xcode_14.3.1.app
-        sudo ln -s "$(brew --prefix llvm@15)/bin/clang" /usr/local/bin/clang++-15
+        sudo apt-get install -y clang-19
 
-    - name: Prepare compilers - Ubuntu 24.04
-      if: matrix.os == 'ubuntu-24.04'
-      run: |
-        sudo sudo apt-get install clang-19
+    - name: Set up MSVC - Windows
+      if: startsWith(matrix.os, 'windows')
+      uses: ilammy/msvc-dev-cmd@v1
+      with:
+        vsversion: ${{ matrix.vs_version }}
 
-    - name: Run regression tests - Linux and macOS version
-      if: startsWith(matrix.os, 'ubuntu') || startsWith(matrix.os, 'macos')
+    - name: Run regression tests
+      shell: bash
       run: |
+        git config --local core.autocrlf false
         cd regression-tests
         bash run-tests.sh -c ${{ matrix.compiler }} -s ${{ matrix.cxx_std }} -d ${{ matrix.stdlib }} -l ${{ matrix.os }}
 
-    - name: Run regression tests - Windows version
-      if: startsWith(matrix.os, 'windows')
-      run: |
-        "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars64.bat" && ^
-        git config --local core.autocrlf false && ^
-        cd regression-tests && ^
-        bash run-tests.sh -c ${{ matrix.compiler }} -s ${{ matrix.cxx_std }} -d ${{ matrix.stdlib }} -l ${{ matrix.os }}
-      shell: cmd
-
     - name: Upload patch
       if: success() || failure()
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v7
       with:
         name: ${{ matrix.os }}-${{ matrix.compiler }}-${{ matrix.cxx_std }}-${{ matrix.stdlib }}.patch
         path: regression-tests/${{ matrix.os }}-${{ matrix.compiler }}-${{ matrix.cxx_std }}-${{ matrix.stdlib }}.patch
@@ -114,7 +107,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Download all patches
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           path: downloaded-results
 
@@ -129,7 +122,7 @@ jobs:
 
       - name: Upload aggregated results
         if: steps.prepare_files.outputs.patch_count != '0'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: aggregated-results
           path: aggregated-results

regression-tests/run-tests.sh

@@ -143,7 +143,8 @@ exclude_test_filter=""
 if [[ "$cxx_compiler" == *"cl.exe"* ]]; then
     compiler_cmd="cl.exe -nologo -std:${cxx_std} -MD -EHsc -I ..\..\..\include -Fe:"
     exec_out_dir="$expected_results_dir/msvc-2022-${cxx_std}"
-    compiler_version=$(cl.exe)
+    # cl.exe prints its version banner to stderr
+    compiler_version=$(cl.exe 2>&1 >/dev/null)
 else
     # Verify the compiler command
     which "$cxx_compiler" > /dev/null

regression-tests/test-results/msvc-2022-c++20/mixed-autodiff-taylor.cpp.output

@@ -0,0 +1,8 @@
+mixed-autodiff-taylor.cpp
+cpp2taylor.h2(7): error C2079: 'cpp2::taylor<double,6>::v' uses undefined class 'std::array<R,6>'
+        with
+        [
+            R=double
+        ]
+cpp2taylor.h2(7): note: the template instantiation context (the oldest one first) is
+mixed-autodiff-taylor.cpp2(6): note: see reference to class template instantiation 'cpp2::taylor<double,6>' being compiled

regression-tests/test-results/msvc-2022-c++20/mixed-parameter-passing.cpp.output

@@ -6,3 +6,6 @@ mixed-parameter-passing.cpp2(44): error C2079: 'container<int>::buf' uses undefi
         ]
 mixed-parameter-passing.cpp2(44): note: the template instantiation context (the oldest one first) is
 mixed-parameter-passing.cpp2(54): note: see reference to class template instantiation 'container<int>' being compiled
+mixed-parameter-passing.cpp2(44): error C2439: 'container<int>::buf': member could not be initialized
+mixed-parameter-passing.cpp2(44): note: see declaration of 'container<int>::buf'
+mixed-parameter-passing.cpp2(54): note: see reference to function 'container<int>::container(void)'

regression-tests/test-results/msvc-2022-c++20/pure2-assert-expected-not-null.cpp.output

@@ -1,22 +1,20 @@
 pure2-assert-expected-not-null.cpp
 pure2-assert-expected-not-null.cpp2(7): error C2039: 'expected': is not a member of 'std'
-predefined C++ types (compiler internal)(357): note: see declaration of 'std'
+C:\Program Files\Microsoft Visual Studio\18\Enterprise\VC\Tools\MSVC\14.51.36231\include\variant(37): note: see declaration of 'std'
 pure2-assert-expected-not-null.cpp2(7): error C2062: type 'int' unexpected
 pure2-assert-expected-not-null.cpp2(7): error C2143: syntax error: missing ';' before '{'
 pure2-assert-expected-not-null.cpp2(7): error C2143: syntax error: missing ';' before '}'
 pure2-assert-expected-not-null.cpp2(9): error C2065: 'ex': undeclared identifier
-pure2-assert-expected-not-null.cpp2(9): error C2672: 'cpp2::impl::assert_not_null': no matching overloaded function found
-..\..\..\include\cpp2util.h(1132): note: could be 'decltype(auto) cpp2::impl::assert_not_null(_T0 &&,std::source_location)'
+pure2-assert-expected-not-null.cpp2(9): error C2100: you cannot dereference an operand of type '<error>'
 pure2-assert-expected-not-null.cpp2(14): error C2039: 'expected': is not a member of 'std'
-predefined C++ types (compiler internal)(357): note: see declaration of 'std'
+C:\Program Files\Microsoft Visual Studio\18\Enterprise\VC\Tools\MSVC\14.51.36231\include\variant(37): note: see declaration of 'std'
 pure2-assert-expected-not-null.cpp2(14): error C2062: type 'int' unexpected
 pure2-assert-expected-not-null.cpp2(14): error C2143: syntax error: missing ';' before '{'
 pure2-assert-expected-not-null.cpp2(14): error C2039: 'unexpected': is not a member of 'std'
-predefined C++ types (compiler internal)(357): note: see declaration of 'std'
+C:\Program Files\Microsoft Visual Studio\18\Enterprise\VC\Tools\MSVC\14.51.36231\include\variant(37): note: see declaration of 'std'
 pure2-assert-expected-not-null.cpp2(14): error C2660: 'unexpected': function does not take 1 arguments
-C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.43.34808\include\eh.h(33): note: see declaration of 'unexpected'
+C:\Program Files\Microsoft Visual Studio\18\Enterprise\VC\Tools\MSVC\14.51.36231\include\eh.h(33): note: see declaration of 'unexpected'
 pure2-assert-expected-not-null.cpp2(14): note: while trying to match the argument list '(bool)'
 pure2-assert-expected-not-null.cpp2(14): error C2143: syntax error: missing ';' before '}'
 pure2-assert-expected-not-null.cpp2(15): error C2065: 'ex': undeclared identifier
-pure2-assert-expected-not-null.cpp2(15): error C2672: 'cpp2::impl::assert_not_null': no matching overloaded function found
-..\..\..\include\cpp2util.h(1132): note: could be 'decltype(auto) cpp2::impl::assert_not_null(_T0 &&,std::source_location)'
+pure2-assert-expected-not-null.cpp2(15): error C2100: you cannot dereference an operand of type '<error>'