Wasted the whole day on trying to make Hunspell work with Emacs on Windows
and still out of luck.

(setq ispell-program-name (executable-find "hunspell"))
(setq ispell-dictionary "en_US")

(require 'ispell)


This is the most basic configuration that should definitely work.

$ hunspell -D
> SEARCH PATH:
> .;C:/Tools/x64/MSYS2/mingw64/bin/;C:/Tools/x64/MSYS2/mingw64/share/hunspell;C:/Tools/x64/MSYS2/mingw64/share/myspell;C:/Tools/x64/MSYS2/mingw64/share/myspell/dicts;%USERPROFILE%\/Application
> Data/OpenOffice.org
> 2/user/wordbook;C:/Tools/x64/MSYS2/mingw64/share/hunspell;C:/Tools/x64/MSYS2/mingw64/share/myspell;C:/Tools/x64/MSYS2/mingw64/share/myspell/dicts
> AVAILABLE DICTIONARIES (path is not mandatory for -d option):
> LOADED DICTIONARY:
> C:/Tools/x64/MSYS2/mingw64/share/hunspell/en_US.aff
> C:/Tools/x64/MSYS2/mingw64/share/hunspell/en_US.dic
> Hunspell 1.3.3


I keep getting:

ispell-phaf: No matching entry for ...


and it's no surprise because `ispell-hunspell-dict-paths-alist' is `nil'.
Why?