diff --git a/ChangeLog b/ChangeLog
index a8ffee2cdb..264d44aa08 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Thu May 31 08:20:14 2012  Eric Hodel  <drbrain@segment7.net>
+
+	* ext/dl/lib/dl/struct.rb (DL::CUnionEntity::size):  Fixed ::size to
+	  return the size of the union.
+	* test/dl/test_c_union_entity.rb:  Test for DL::CUnionEntity::size
+
 Thu May 31 07:45:43 2012  Eric Hodel  <drbrain@segment7.net>
 
 	* ext/dl:  Added documentation.  Patch by Vincent Batts.
diff --git a/ext/dl/lib/dl/struct.rb b/ext/dl/lib/dl/struct.rb
index 27f6b42fd2..23f28bbaa3 100644
--- a/ext/dl/lib/dl/struct.rb
+++ b/ext/dl/lib/dl/struct.rb
@@ -234,17 +234,9 @@ module DL
     #                          DL::TYPE_VOIDP])
     #   => 8
     def CUnionEntity.size(types)
-      size   = 0
-      types.each_with_index{|t,i|
-        if( t.is_a?(Array) )
-          tsize = PackInfo::SIZE_MAP[t[0]] * t[1]
-        else
-          tsize = PackInfo::SIZE_MAP[t]
-        end
-        if( tsize > size )
-          size = tsize
-        end
-      }
+      types.map { |type, count = 1|
+        PackInfo::SIZE_MAP[type] * count
+      }.max
     end
 
     # Given +types+, calculate the necessary offset and for each union member
diff --git a/test/dl/test_c_union_entity.rb b/test/dl/test_c_union_entity.rb
new file mode 100644
index 0000000000..8c72a664eb
--- /dev/null
+++ b/test/dl/test_c_union_entity.rb
@@ -0,0 +1,18 @@
+require_relative 'test_base'
+
+require 'dl/cparser'
+
+class DL::TestCUnionEntity < DL::TestBase
+  def test_class_size
+    size = DL::CUnionEntity.size([DL::TYPE_DOUBLE, DL::TYPE_CHAR])
+
+    assert_equal DL::SIZEOF_DOUBLE, size
+  end
+
+  def test_class_size_with_count
+    size = DL::CUnionEntity.size([[DL::TYPE_DOUBLE, 2], [DL::TYPE_CHAR, 20]])
+
+    assert_equal DL::SIZEOF_CHAR * 20, size
+  end
+end
+