diff --git a/dlls/wined3d/wined3d_main.c b/dlls/wined3d/wined3d_main.c
index 08d1554c4f1..526c7492531 100644
--- a/dlls/wined3d/wined3d_main.c
+++ b/dlls/wined3d/wined3d_main.c
@@ -96,7 +96,7 @@ struct wined3d * CDECL wined3d_create(UINT version, DWORD flags)
     struct wined3d *object;
     HRESULT hr;
 
-    object = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*object));
+    object = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, FIELD_OFFSET(struct wined3d, adapters[1]));
     if (!object)
     {
         ERR("Failed to allocate wined3d object memory.\n");