diff -r 7a3e67bfa417 -r 16b5df5792a8 mercurial/scmposix.py
--- a/mercurial/scmposix.py	Mon Dec 19 00:28:12 2016 +0530
+++ b/mercurial/scmposix.py	Mon Dec 19 02:15:24 2016 +0530
@@ -25,7 +25,7 @@
 
 def systemrcpath():
     path = []
-    if sys.platform == 'plan9':
+    if pycompat.sysplatform == 'plan9':
         root = 'lib/mercurial'
     else:
         root = 'etc/mercurial'
@@ -38,7 +38,7 @@
     return path
 
 def userrcpath():
-    if sys.platform == 'plan9':
+    if pycompat.sysplatform == 'plan9':
         return [encoding.environ['home'] + '/lib/hgrc']
     else:
         return [os.path.expanduser('~/.hgrc')]