Name: gsC80088 Date: 03/06/99


VERSION INFORMATION:

  java version "1.2"
  Classic VM (build JDK-1.2-V, native threads)
  java full version "JDK-1.2-V"

I'm running on Windows NT 4.0 (service pack 3).


SOURCE CODE (1): OverFlowTest.java

  public class OverFlowTest {
   public static void main(String[] a) {
    loopForever();
   }

   public static final void loopForever() {
    loopForever();
   }
  }


SOURCE CODE (2): OverFlowTest2.java

  class OverFlowTest2 {
   public static void main(String[] g) {
    OverFlowTest2 a = new OverFlowTest2();

    System.out.println(a.loop(100000));
   }

   public final int loop(int n) {
    if (n % 100 == 0) {
     System.out.println(""+n+" to go...");
    }
    if (n == 0) {
     return 1;
    } else {
     return loop(n-1);
    }
   }
  }


My understanding is that the first of these programs should throw a StackOverflowError (or run forever if the compiler does tail-call optimisation), and the second should either throw a StackOverflowError or terminate, printing "1". Observed behaviour is as follows:


TRANSCRIPT:

> javac OverFlowTest.java

> java OverFlowTest
A nonfatal internal JIT (3.00.078(x)) error 'Structured Exception(c00000fd)' has occurred in :
  'OverFlowTest.loopForever ()V': Interpreting method.
  Please report this error in detail to http://java.sun.com/cgi-bin/bugreport.cgi

Exception in thread "main" java.lang.StackOverflowError
        at OverFlowTest.loopForever(OverFlowTest.java:7)
        at OverFlowTest.loopForever(OverFlowTest.java:7)
        at OverFlowTest.loopForever(OverFlowTest.java:7)
        at OverFlowTest.loopForever(OverFlowTest.java:7)
        at OverFlowTest.loopForever(OverFlowTest.java:7)
        at OverFlowTest.loopForever(OverFlowTest.java:7)
[many more identical lines removed from transcript]


> javac OverFlowTest2.java

> java OverFlowTest2
100000 to go...
99900 to go...
99800 to go...
99700 to go...
99600 to go...
99500 to go...
99400 to go...
[... many similar lines removed from transcript ...]
57600 to go...
57500 to go...
57400 to go...
57300 to go...

At this point, java crashes and I get a dialog from Windows NT:

java.exe - Application Error
The exception unknown software exception (0xc00000fd) occurred in the application at location 0x78003367
Click on OK to terminate the application
Click on CANCEL to debug the application

I haven't tried, but perhaps there's a danger that a program like this could crash someone's browser.

Please contact me at ###@###.### if you require more information on this behaviour.
(Review ID: 54881)
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