diff --git a/sphinx/environment.py b/sphinx/environment.py
index 43e0262bf..1f8e00f56 100644
--- a/sphinx/environment.py
+++ b/sphinx/environment.py
@@ -189,7 +189,8 @@ class CitationReferences(Transform):
         for citnode in self.document.traverse(nodes.citation_reference):
             cittext = citnode.astext()
             refnode = addnodes.pending_xref(cittext, reftype='citation',
-                                            reftarget=cittext)
+                                            reftarget=cittext, refwarn=True)
+            refnode.line = citnode.line or citnode.parent.line
             refnode += nodes.Text('[' + cittext + ']')
             citnode.parent.replace(citnode, refnode)
 
diff --git a/sphinx/roles.py b/sphinx/roles.py
index 1511e35f9..307439146 100644
--- a/sphinx/roles.py
+++ b/sphinx/roles.py
@@ -300,7 +300,7 @@ specific_docroles = {
     # links to download references
     'download': XRefRole(nodeclass=addnodes.download_reference),
     # links to documents
-    'doc': XRefRole(),
+    'doc': XRefRole(warn_dangling=True),
 
     'pep': indexmarkup_role,
     'rfc': indexmarkup_role,