Issues with Emacs master?

[Angelo Graziosi]

After about a month, I have built master (b49d98, 2019-08-02 12:24:53) and 
noticed that with Python files (.py) it flags

  "Can’t guess python-indent-offset, using defaults: 4"

(in the minibuffer or in Messages). Really this message is present also in 
previous builds but in the current, if I try

C-h v pyth TAB

(to know about python-indent-offset) I get in the minibuffer, 

- on Windows (MSYS2/MINGW64 build):

  "Shell native completion is disabled, using fallback"

- on GNU/Linux Mint 19.1 (Cairo build):

  "Shell native completion is enabled."

It seems that these message show up only if the variable start with the string 
'py' or 'pyt' or 'pyth' etc. Trying with 'pr', 'pri'.. 'ps', 'ps-sp'.. there is 
the completion without any message..

In previous builds (2019-06-30 11:23:06), on both systems, no message but the 
completion oh pyth in python- etc.

Maybe a python-mode regression/issue

Ciao,  
  Angelo.