dev-python/pip/files/pip-disable-system-install.patch

From 847553da616edabede18c69ba640a32b719b45a8 Mon Sep 17 00:00:00 2001
From: Mike Gilbert <floppym@gentoo.org>
Date: Tue, 27 Oct 2015 12:20:44 -0400
Subject: [PATCH] install: Raise an error to avoid breaking python-exec

Running pip without --target, --root, or --user will result in packages
being installed systemwide. This has a tendency to break python-exec if
setuptools gets installed or upgraded.
---
 pip/commands/install.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pip/commands/install.py b/pip/commands/install.py
index 46cd9f2..36b72f2 100644
--- a/pip/commands/install.py
+++ b/pip/commands/install.py
@@ -204,6 +204,9 @@ class InstallCommand(RequirementCommand):
             )
             options.ignore_installed = True
 
+        if not options.use_user_site and not options.target_dir and not options.root_path:
+            raise CommandError("(Gentoo) Please run pip with the --user option to avoid breaking python-exec")
+
         if options.build_dir:
             options.build_dir = os.path.abspath(options.build_dir)
 
-- 
2.6.2