diff -r 8e7db961535a -r a9cecc7b68d3 mercurial/hgweb/__init__.py
--- a/mercurial/hgweb/__init__.py	Tue Dec 01 16:06:20 2015 -0800
+++ b/mercurial/hgweb/__init__.py	Sat Oct 31 22:26:50 2015 +0900
@@ -104,12 +104,12 @@
         if repo and repo.ui != baseui:
             repo.ui.setconfig("web", o, val, 'serve')
 
-    o = opts.get('web_conf') or opts.get('webdir_conf')
-    if not o:
+    webconf = opts.get('web_conf') or opts.get('webdir_conf')
+    if webconf:
+        app = hgwebdir_mod.hgwebdir(webconf, baseui=baseui)
+    else:
         if not repo:
             raise error.RepoError(_("there is no Mercurial repository"
                                     " here (.hg not found)"))
-        o = repo
-
-    app = hgweb(o, baseui=baseui)
+        app = hgweb_mod.hgweb(repo, baseui=baseui)
     return httpservice(ui, app, opts)