diff --git a/odoo/addons/test_new_api/tests/test_new_fields.py b/odoo/addons/test_new_api/tests/test_new_fields.py
index 578ad04d6f1..de9bc11dcaf 100644
--- a/odoo/addons/test_new_api/tests/test_new_fields.py
+++ b/odoo/addons/test_new_api/tests/test_new_fields.py
@@ -928,25 +928,38 @@ class TestFields(common.TransactionCase):
         with self.assertRaises(AccessError):
             cat1.name
 
-    def test_40_new(self):
-        """ test new records. """
+    def test_40_new_defaults(self):
+        """ Test new records with defaults. """
+        user = self.env.user
         discussion = self.env.ref('test_new_api.discussion_0')
 
-        # create a new message
-        message = self.env['test_new_api.message'].new()
-        self.assertFalse(message.id)
+        # create a new message; fields have their default value if not given
+        new_msg = self.env['test_new_api.message'].new({'body': "XXX"})
+        self.assertFalse(new_msg.id)
+        self.assertEqual(new_msg.body, "XXX")
+        self.assertEqual(new_msg.author, user)
 
         # assign some fields; should have no side effect
-        message.discussion = discussion
-        message.body = BODY = "May the Force be with you."
-        self.assertEqual(message.discussion, discussion)
-        self.assertEqual(message.body, BODY)
-        self.assertFalse(message.author)
-        self.assertNotIn(message, discussion.messages)
+        new_msg.discussion = discussion
+        new_msg.body = "YYY"
+        self.assertEqual(new_msg.discussion, discussion)
+        self.assertEqual(new_msg.body, "YYY")
+        self.assertNotIn(new_msg, discussion.messages)
 
         # check computed values of fields
-        self.assertEqual(message.name, "[%s] %s" % (discussion.name, ''))
-        self.assertEqual(message.size, len(BODY))
+        self.assertEqual(new_msg.name, "[%s] %s" % (discussion.name, user.name))
+        self.assertEqual(new_msg.size, 3)
+
+        # extra tests for x2many fields with default
+        cat1 = self.env['test_new_api.category'].create({'name': "Cat1"})
+        cat2 = self.env['test_new_api.category'].create({'name': "Cat2"})
+        discussion = discussion.with_context(default_categories=[(4, cat1.id)])
+        # no value gives the default value
+        new_disc = discussion.new({'name': "Foo"})
+        self.assertEqual(new_disc.categories, cat1)
+        # value is combined with default value
+        new_disc = discussion.new({'name': "Foo", 'categories': [(4, cat2.id)]})
+        self.assertEqual(new_disc.categories, cat1 + cat2)
 
     @mute_logger('odoo.addons.base.models.ir_model')
     def test_41_new_related(self):
diff --git a/odoo/fields.py b/odoo/fields.py
index db533ecbb51..25cdcfe1adb 100644
--- a/odoo/fields.py
+++ b/odoo/fields.py
@@ -1116,12 +1116,20 @@ class Field(MetaField('DummyField', (object,), {})):
     def determine_draft_value(self, record):
         """ Determine the value of ``self`` for the given draft ``record``. """
         if self.compute:
-            fields = record._field_computed[self]
-            with record.env.protecting(fields, record):
-                self._compute_value(record)
-        else:
-            null = self.convert_to_cache(False, record, validate=False)
-            record.env.cache.set_special(record, self, lambda: null)
+            return self.compute_value(record)
+
+        null = self.convert_to_cache(False, record, validate=False)
+        record.env.cache.set_special(record, self, lambda: null)
+
+        defaults = record.default_get([self.name])
+        if self.name in defaults:
+            # The null value above is necessary to convert x2many field values.
+            # For instance, converting [(4, id)] accesses the field's current
+            # value, then adds the given id. Without an initial value, the
+            # conversion ends up here to determine the field's value, and this
+            # generates an infinite recursion.
+            value = self.convert_to_cache(defaults[self.name], record)
+            return record.env.cache.set(record, self, value)
 
     def determine_inverse(self, records):
         """ Given the value of ``self`` on ``records``, inverse the computation. """