commit 1000565c3a2439c9a7c9759284814dbf3b8bc20d
author Bram Moolenaar <Bram@vim.org> Thu Dec 31 21:03:23 2015 +0100
committer Bram Moolenaar <Bram@vim.org> Thu Dec 31 21:03:23 2015 +0100
tree 357f2fbcb81da653f6786b30175f13e3882361b7
parent 2bf2417612879de627dcea1dbb22ee2199b16963

patch 7.4.1012
Problem:    Vim overwrites the value of $PYTHONHOME.
Solution:   Do not set $PYTHONHOME if it is already set. (Kazuki Sakamoto,
            closes #500)

src/if_python3.c

diff --git a/src/if_python3.c b/src/if_python3.c
index 721e3cc..387b811 100644
--- a/src/if_python3.c
+++ b/src/if_python3.c
@@ -858,7 +858,10 @@
 
 
 #ifdef PYTHON3_HOME
-	Py_SetPythonHome(PYTHON3_HOME);
+# ifdef DYNAMIC_PYTHON3
+	if (mch_getenv((char_u *)"PYTHONHOME") == NULL)
+# endif
+	    Py_SetPythonHome(PYTHON3_HOME);
 #endif
 
 	PyImport_AppendInittab("vim", Py3Init_vim);