src/jdk/nashorn/internal/codegen/TypeEvaluator.java

*** 237,247 ****
                          if (returnType == Type.BOOLEAN) {
                              // We don't have optimistic booleans. In fact, optimistic call sites getting back boolean
                              // currently deoptimize all the way to Object.
                              return Type.OBJECT;
                          }
!                         assert returnType == Type.INT || returnType == Type.LONG || returnType == Type.NUMBER || returnType == Type.OBJECT;
                          return returnType;
                      }
                  }
              }
          }
--- 237,247 ----
                          if (returnType == Type.BOOLEAN) {
                              // We don't have optimistic booleans. In fact, optimistic call sites getting back boolean
                              // currently deoptimize all the way to Object.
                              return Type.OBJECT;
                          }
!                         assert returnType == Type.INT || returnType == Type.NUMBER || returnType == Type.OBJECT;
                          return returnType;
                      }
                  }
              }
          }