image:- Visual Studio 2017 environment:  matrix:    - generator: "Visual Studio 15 2017"      artifact: "ON"    - generator: "MSYS Makefiles"      artifact: "ON"    - generator: "Visual Studio 15 2017"      shared: "OFF"      artifact: "OFF"    - generator: "Visual Studio 15 2017"      shared: "ON"      artifact: "OFF"    - generator: "MSYS Makefiles"      shared: "OFF"      artifact: "OFF"    - generator: "MSYS Makefiles"      shared: "ON"      artifact: "OFF" matrix:  fast_finish: true build_script:  - ps: |      $env:Path = "C:\msys64\mingw64\bin;C:\msys64\usr\bin;" + $env:Path      bash -lc "pacman -S --needed --noconfirm mingw-w64-x86_64-fftw mingw-w64-x86_64-libsndfile"      mkdir build      cd build      if ($env:artifact -eq 'OFF')      {          cmake -G "$env:generator" -DBUILD_SHARED_LIBS=$env:shared ..          cat config.h          cmake --build .          ctest -C "Debug"      }      else      {          cmake .. -G "$env:generator" -DBUILD_SHARED_LIBS=OFF -DCMAKE_INSTALL_PREFIX=artifact          cmake --build . --config Release --target install          cmake .. -G "$env:generator" -DBUILD_SHARED_LIBS=ON -DCMAKE_INSTALL_PREFIX=artifact          cmake --build . --config Release --target install          Compress-Archive -Path artifact\* -Destination artifact          Push-AppveyorArtifact artifact.zip      }