Index: tests/pybin/settings.py
===================================================================
--- tests/pybin/settings.py	(revision 6daaee3ee6c5b06026c6165d074be69373159877)
+++ tests/pybin/settings.py	(revision 17bc05bc4cc8fb4a81bde09b5c4ca270bd1804f1)
@@ -135,4 +135,6 @@
 	timeout      = Timeouts(options.timeout, options.global_timeout)
 
+	# if we distribute, distcc errors will fail tests, use log file for distcc
+	# don't use "'DISTCC_LOG' not in os.environ" because it can be set to ''
 	if distribute and not os.environ.get('DISTCC_LOG'):
 		os.putenv('DISTCC_LOG', os.path.join(BUILDDIR, 'distcc_error.log'))