what optimizations are invalid in java?

Wed Mar 13 11:35:00 GMT 2002

Robert Dewar writes:
 > "if the dividend is the negative integer of largest possible magnitude
 > for its type, and the divisor is -1, then integer overflow occurs and
 > the result is equal to the dividend. Despite the overflow, no
 > exception is thrown in this case. On the other hand, if the value of
 > the divisor in an integer division is 0, then an ArithmeticException
 > is thrown."
 > 
 > That's probably a concession to the x86, which has a bug on this specific
 > point.
No, the x86 generates a trap for all divide overflows.
 > It's really HORRIBLE to see Ada code specifically testing for this
 > case to determine whether to raise an exception :-(
There's some code in libgcj that does the same thing.
Andrew.