commit https://github.com/vim/vim/commit/1000565c3a2439c9a7c9759284814dbf3b8bc20d Author: Bram Moolenaar <Bram@vim.org> Date: Thu Dec 31 21:03:23 2015 +0100 patch 7.4.1012 Problem: Vim overwrites the value of $PYTHONHOME. Solution: Do not set $PYTHONHOME if it is already set. (Kazuki Sakamoto, closes https://github.com/vim/vim/issues/500)

README_src.txt for version 7.4 of Vim: Vi IMproved.

The source archive contains the files needed to compile Vim on Unix systems.
It is packed for Unix systems (NL line separator).

For more information, see the README.txt file that comes with the runtime
archive (vim-7.4-rt.tar.gz).  To be able to run Vim you MUST get the runtime
archive too!