diff --git a/std/experimental/allocator/building_blocks/region.d b/std/experimental/allocator/building_blocks/region.d
index 77ded986a..2197f2992 100644
--- a/std/experimental/allocator/building_blocks/region.d
+++ b/std/experimental/allocator/building_blocks/region.d
@@ -529,7 +529,7 @@ struct InSituRegion(size_t size, size_t minAlign = platformAlignment)
     union
     {
         private ubyte[size] _store = void;
-        private double _forAlignmentOnly1 = void;
+        private double _forAlignmentOnly1;
     }
     // }