diff --git a/ChangeLog b/ChangeLog
index 1c342313d5..c9ddbf848c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+Fri Aug  2 23:57:57 2013  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* vm.c (m_core_define_method, m_core_define_singleton_method): now
+	  the value of def-expr is the Symbol of the name of the method, not
+	  nil.
+	  ref. [ruby-dev:42151] [Feature #3753]
+
+	* test/ruby/test_syntax.rb (TestSyntax#test_value_of_def): test for
+	  above changes.
+
 Fri Aug  2 23:54:11 2013  Masaki Matsushita  <glass.saga@gmail.com>
 
 	* array.c (rb_ary_zip): performance improvement by avoiding
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
index 9daa0e4d49..99470691ef 100644
--- a/test/ruby/test_syntax.rb
+++ b/test/ruby/test_syntax.rb
@@ -370,6 +370,13 @@ eom
     end
   end
 
+  def test_value_of_def
+    assert_separately [], <<-EOS
+      assert_equal(:foo, (def foo; end))
+      assert_equal(:foo, (def (Object.new).foo; end))
+    EOS
+  end
+
   private
 
   def not_label(x) @result = x; @not_label ||= nil end
diff --git a/vm.c b/vm.c
index 8e01a17dc1..3150ee8ac6 100644
--- a/vm.c
+++ b/vm.c
@@ -2052,7 +2052,7 @@ m_core_define_method(VALUE self, VALUE cbase, VALUE sym, VALUE iseqval)
     REWIND_CFP({
 	vm_define_method(GET_THREAD(), cbase, SYM2ID(sym), iseqval, 0, rb_vm_cref());
     });
-    return Qnil;
+    return sym;
 }
 
 static VALUE
@@ -2061,7 +2061,7 @@ m_core_define_singleton_method(VALUE self, VALUE cbase, VALUE sym, VALUE iseqval
     REWIND_CFP({
 	vm_define_method(GET_THREAD(), cbase, SYM2ID(sym), iseqval, 1, rb_vm_cref());
     });
-    return Qnil;
+    return sym;
 }
 
 static VALUE