fixes #2216

tests/notnil/tnotnil_in_generic.nim

@@ -0,0 +1,27 @@
+discard """
+  errormsg: "cannot prove 'x' is not nil"
+"""
+
+# bug #2216
+
+type
+    A[T] = ref object
+        x: int
+        ud: T
+
+proc good[T](p: A[T]) = 
+    discard
+
+proc bad[T](p: A[T] not nil) = 
+    discard
+
+
+proc go() = 
+    let s = A[int](x: 1)
+
+    good(s)
+    bad(s)
+    var x: A[int]
+    bad(x)
+
+go()