diff --git a/mercurial/revset.py b/mercurial/revset.py
--- a/mercurial/revset.py
+++ b/mercurial/revset.py
@@ -2642,14 +2642,15 @@ class addset(abstractsmartset):
             self._ascending = not self._ascending
 
     def first(self):
-        if self:
-            return self._list.first()
+        for x in self:
+            return x
         return None
 
     def last(self):
-        if self:
-            return self._list.last()
-        return None
+        self.reverse()
+        val = self.first()
+        self.reverse()
+        return val
 
 class generatorset(abstractsmartset):
     """Wrap a generator for lazy iteration
diff --git a/tests/test-mq.t b/tests/test-mq.t
--- a/tests/test-mq.t
+++ b/tests/test-mq.t
@@ -1581,3 +1581,19 @@ Test that secret mq patch does not break
   tip	[0-9a-f]{40} (re)
 
   $ cd ..
+
+Test interraction with revset (issue4426)
+
+  $ hg init issue4426
+  $ cd issue4426
+
+  $ echo a > a
+  $ hg ci -Am a
+  adding a
+  $ echo a >> a
+  $ hg ci -m a
+  $ echo a >> a
+  $ hg ci -m a
+  $ hg qimport -r 0::
+
+  $ cd ..