bug#14002: Acknowledgement (24.3.50; buffer-file-coding-system is undecided-dos, everywhere)

[Dmitry Gutov]

Some more info:

With emacs -Q, the coding system is undecided-dos during opening, 
modification and saving. If I then do vc-revert, it becomes 
undecided-unix, and the subsequent editing of the file works as expected.

In my usual setup, I have

(set-language-environment 'Cyrillic-CP1251) ; defined previously
(set-file-name-coding-system 'cp1251)
(prefer-coding-system 'utf-8)

and the coding system in this scenario goes from utf-8 to utf-8-dos 
(after saving) to undecided-unix (after reverting), and then editing 
similarly works fine.