in reply to SUPER delegation fails because class name getting munged (somehow?)

As it always seems to be just one bit flipping, it could also be hardware-related memory corruption.

I once had similar problems with very strange things happening occasionally.  At first, problems only occurred very seldomly, then more and more often. After quite a bit of hunting in the wrong places, it eventually turned out to be the power supply slowly getting flaky (voltage slowly dropping, and having more DC ripples than allowed).

So, if you can take the machine down, run a memory tester (such as memtest86).

Also, have maybe other strange things been happening on the machine?  For example, compiling huge programs has always been a good (indirect) "memory test" for me, as compilers tend to be quite sensitive to corrupted memory, and usually randomly crash as a result...

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Re^2: SUPER delegation fails because class name getting munged (somehow?)
by jethro (Monsignor) on Feb 23, 2011 at 16:54 UTC
    O is decimal 79 is binary 01001111, P is decimal 80 is binary 01010000. So this is not bit flipping, there is something really substracting 1

      Ok, my fault.  The "argument" still holds, though, as hardware memory corruption mustn't necessarily result in only single bits flipping — it just happened to begin that way in the limited number of cases I've observed so far. I.e., the memtest statistics (after running for a couple of days) showed a clear pattern of certain "bit lines" flipping far more frequently than others.

        Flipping of more than one bit is possible and probably quite common, but to have bits flip so that always a substraction of 1 comes out is just very unlikely. I did check the other two examples and while one was similar to the case I posted about, the other one was just a flip of the lowest bit.