anchor.diff:  @if NOT EXIST "%vsenv%" @set toolchain=Visual Studio 14
   @if NOT EXIST "%vsenv%" @set vsenv=%VS140COMNTOOLS%..\..\VC\bin\vcvars%minabi%.bat
   @set gcc=%mesa%mingw-w64-%abi%\mingw%minabi%\bin
  -@set PATH=%mesa%flexbison\;%mesa%m4\%abi%\bin\;%mesa%cmake\%abi%\bin\;%PATH%
  -@if EXIST "%gcc%" set PATH=%gcc%\;%PATH%
   @set vsenvloaded=0
  +@set dxtnbuilt=0
   @set /p buildllvm=Begin LLVM build. Only needs to run once for each ABI and version. Proceed y/n? 
   @if /I NOT %buildllvm%==y GOTO build_dxtn
   
  
positive.code: :build_dxtn
  @if NOT EXIST "%gcc%" GOTO build_mesa
  @if NOT EXIST "%mesa%dxtn" GOTO build_mesa
  @set /p builddxtn=Do you want to build S3 texture compression library? (y/n):
  @if /i NOT %builddxtn%==y GOTO build_mesa
  @cd "%mesa%dxtn"
  
negative.code: @set mingw=n
  @set mingwtest=0
  @if EXIST "%gcc%" @set mingwtest=1
  @if %dxtnbuilt%==0 set PATH=%gcc%\;%PATH%
  @set msys2=%mesa%msys64\msys2_shell.cmd
  @if EXIST "%msys2%" @set mingwtest=%mingwtest%2
  @rem if %mingwtest%==12 @set /p mingw=Do you want to build with MinGW-W64 instead of Visual Studio (y=yes):
  @set buildmingw=
  @set PATH=%mesa%Python\%abi%\;%mesa%Python\%abi%\Scripts\;%mesa%flexbison\;%mesa%m4\%abi%\usr\bin\;%PATH%
  @pip install -U mako
  @pip freeze > requirements.txt
  @pip install -r requirements.txt --upgrade
  