classFoo{overridedefequals(o:Any)=false;overridedefhashCode=1}// should not result in a stack overflowobjectTest{defmain(args:Array[String]):Unit={importcollection.immutable.HashMapvarm=Map[Foo,Int]()for(i<-1to30000)m+=(newFoo)->iassert(m.size==30000)m.toString}}