WIP: Try to find pjwHash64 that only fit in Long

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/tasty/TastyPickler.scala

@@ -89,6 +89,7 @@ class TastyPickler(val rootCls: ClassSymbol) {
       h &= ~high
       i += 1
     }
+    assert(Int.MinValue.toLong <= h && h <= Int.MaxValue.toLong, "This should fail 50% of the time")
     h
   }
 }