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Re: Gcc certification


Joe Buck wrote:

You can't skip validating the tables.

One would think that should be the case, but you are arguing what should be, not what is (referencing the Do178B standard :-) One big loop hole is that you can move stuff into the hardware, and hardware does not have the same rigourous certification standards as software.

The famous Pentium bug, which reportedly cost Intel 470 million dollars, was due to an incorrectly generated table (the table was originally correct, but the script to embed the table into a programmable logic array had a bug). Five positions in a lookup table used by the microcode for the division instruction had the wrong value.

And most certainly applications could be certified on that flawed Pentium :-)


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