fixes #12826

tests/destructor/tcomplexobjconstr.nim

@@ -0,0 +1,33 @@
+discard """
+  output: "true"
+  cmd: "nim c --gc:arc $file"
+"""
+
+# bug #12826
+
+type
+  MyObject1* = object of RootObj
+    z*: string
+
+  MyObject2* = object of RootObj
+    x*: float
+    name*: string
+    subobj: MyObject1
+    case flag*: bool
+    of false:
+      more: array[3, MyObject1]
+    of true: y*: float
+
+var x = new(MyObject2)
+assert x of MyObject2
+assert x.subobj of MyObject1
+assert x.more[2] of MyObject1
+assert x.more[2] of RootObj
+
+var y: MyObject2
+assert y of MyObject2
+assert y.subobj of MyObject1
+assert y.more[2] of MyObject1
+assert y.more[2] of RootObj
+
+echo "true"