anchor.diff:  @rem Look for build generators.
   @IF %cmakestate%==0 IF %mesonstate%==0 (
   @echo There is no build system generator suitable for LLVM build.
  -@GOTO prep_mesa
  +@GOTO skipllvm
  +)
  +
  +@rem Disable Meson build for now.
  +@if NOT %mesonstate%==0 if %cmakestate%==0 (
  +@echo Meson build support is not implemented.
  +@GOTO skipllvm
   )
   
   @rem LLVM build getting started.
   @if EXIST %mesa%\llvm set /p buildllvm=Begin LLVM build. Only needs to run once for each ABI and version. Proceed (y/n):
   @if EXIST %mesa%\llvm echo.
  -@if /I NOT "%buildllvm%"=="y" GOTO prep_mesa
  +@if /I NOT "%buildllvm%"=="y" GOTO skipllvm
   @cd %mesa%\llvm
   @if EXIST %abi% RD /S /Q %abi%
   @if EXIST buildsys-%abi% RD /S /Q buildsys-%abi%
  
positive.code: 
  @rem Load Visual Studio environment. Only cmake can load it in the background and only when using MsBuild.
  @if /I NOT "%meson%"=="y" if /I "%ninja%"=="y" call %vsenv%
  @rem if /I "%meson%"=="y" call %vsenv%
  @if /I "%ninja%"=="y" cd %mesa%\llvm\buildsys-%abi%
  @if /I "%meson%"=="y" cd %mesa%\llvm\buildsys-%abi%
  
  @rem Configure and execute the build with the configuration made above.
  
negative.code: @echo.
  @if /I NOT "%meson%"=="y" if /I NOT "%ninja%"=="y" cmake --build . --config Release --target install
  @if /I NOT "%meson%"=="y" if /I "%ninja%"=="y" ninja install
  @if /I "%meson%"=="y" echo Unimplemented code path.
  @echo.
  
  :skipllvm
  