anchor.diff:  
   for 64-bit. For Visual Studio 2005-2013, you need to use one of the shortcuts in
   the "Visual Studio Tools" program group under the main program group for the
  -version of Visual Studio you installed. For Visual Studio 2015, you need to use
  -the shortcuts in the "Windows Desktop Command Prompts" group under the
  -"Visual Studio Tools" group.
  +version of Visual Studio you installed. For Visual Studio 2015 and 2017, you
  +need to use the shortcuts in the "Windows Desktop Command Prompts" (2015) or
  +"VC" (2017) group under the "Visual Studio Tools" group.
   
   Unlike `SetEnv` for the Windows SDK, the architecture is selected by using a
   different shortcut, rather than by running a command.
  
positive.code: 
  For Visual Studio 2012 and 2013, both x86 and x64 Command Prompt shortcuts
  indicate if they are the "Native Tools" or "Cross Tools" versions. Visual Studio
  2015 makes the shortcuts even clearer by including the full name of the
  architecture.
  
  You cannot at present use a cross-compiler to compile 64-bit OCaml on 32-bit
  
negative.code: | Visual Studio 2012 | 17.00.x.x    | 32/64-bit               |
  | Visual Studio 2013 | 18.00.x.x    | 32/64-bit               |
  | Visual Studio 2015 | 19.00.x.x    | 32/64-bit               |
  | Visual Studio 2017 | 19.10.x.x    | 32/64-bit               |
  |=====
  
  [[vs1]]
  