[stdlib] Add test for Bit with-overflow arithmetic bug

PatrickPijnappel · PatrickPijnappel · commit 3e80f8d30ff7 · 2015-12-20T17:30:30.000+11:00
diff --git a/test/1_stdlib/Bit.swift b/test/1_stdlib/Bit.swift
@@ -27,6 +27,8 @@ print(one.predecessor().rawValue)
 
 // CHECK-NEXT: 0
 print((one &+ one).rawValue)
+// CHECK-NEXT: 1
+print((zero &- one).rawValue)
 
 // CHECK: done.
 print("done.")
