Index: pym/portage/__init__.py
===================================================================
--- pym/portage/__init__.py	(revision 10581)
+++ pym/portage/__init__.py	(revision 10582)
@@ -1272,6 +1272,8 @@
 			make_conf = getconfig(
 				os.path.join(config_root, MAKE_CONF_FILE.lstrip(os.path.sep)),
 				tolerant=tolerant, allow_sourcing=True)
+			if make_conf is None:
+				make_conf = {}
 
 			# Allow ROOT setting to come from make.conf if it's not overridden
 			# by the constructor argument (from the calling environment).