'while' statement with 'test' using var before being declared in body results in VerifyError

function f() {
   while (x += 2) { var x = 44 }
}
 
Exception in thread "main" java.lang.VerifyError: get long/double overflows locals
Exception Details:
  Location:
    jdk/nashorn/internal/scripts/Script$test.f(Ljava/lang/Object;)Ljava/lang/Object; @7: dload_2
  Reason:
    Local index 2 is invalid
  Bytecode:
    0000000: a700 0714 002a 4928 1400 2c63 5c49 b800
    0000010: 339a fff2 b200 37b0
  Stackmap Table:
    append_frame(@3,Top,Double)
    chop_frame(@7,2)