Just check paths on Windows.

Author: TheBlackPlague

.github/workflows/py_binding.yml

@@ -127,15 +127,25 @@ jobs:
         if: matrix.os == 'windows-latest'
         shell: powershell
         run: |
-          echo "Detecting STL version using $env:CXX"
+          echo "Detecting MSVC STL version..."
           
-          $cxx_version = & $env:CXX -dM -E -x c++ NUL 2>$null | Select-String '_MSC_VER' | ForEach-Object {
-            if ($_ -match '_MSC_VER\s+(\d+)') {
-              "msvc$($matches[1])"
+          $paths = @(
+            "$env:ProgramFiles\Microsoft Visual Studio",
+            "$env:ProgramFiles (x86)\Microsoft Visual Studio"
+          )
+          
+          $versions = foreach ($base in $paths) {
+            if (Test-Path $base) {
+              Get-ChildItem $base -Recurse -Directory -Depth 5 -ErrorAction SilentlyContinue |
+                Where-Object { $_.FullName -match 'Tools\\MSVC\\(\d+\.\d+)\.' } |
+                ForEach-Object { if ($_ -match 'Tools\\MSVC\\(\d+\.\d+)\.') { $matches[1] } }
             }
           }
           
-          echo "CXX_VERSION=$cxx_version" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+          $stlVersion = $versions | Sort-Object -Descending -Unique | Select-Object -First 1
+          
+          echo "Detected STL Version: $stlVersion"
+          echo "CXX_VERSION=msvc$stlVersion" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
 
       - name: Extract C++ Standard Library Version (Linux & MacOS)
         if: matrix.os != 'windows-latest'