Blog

Verifying numerical precision with Frama-C's value analysis
Pascal Cuoq on 22 January 2011

Frama-C's value analysis wasn't aimed at verifying numerical precision of C functions when it was conceived. There already was a specialized project for this purpose. However the value analysis needed to handle floating-point computations correctly (that is without omitting any of the possible behaviors the function can have at run-time)...

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Why don't you verify the entire Internet ?
Pascal Cuoq on 13 January 2011

... or at least the C codebase available on there, anyway? Don't be fooled by the positive examples presented here and there. Verifying arbitrary programs is still arbitrarily difficult. There is some cherry-picking going on in the results we, and others, present. In the case of Frama-C's value analysis, dynamic...

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Seven errors game
Pascal Cuoq on 11 January 2011

If you have seen the basic presentation of the value analysis, you may remember the following function. void abs(int y) { if (y >= 0) { r = y; return; } else { r = -y; return; } } \Why the two ugly return; statements in a function that needs...

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Documentation
Pascal Cuoq on 10 December 2010

So it may seem that I have a pretty good job for having nothing more important to worry about —that may or may not be accurate— but I worry about the state of the Frama-C documentation in general and of the value analysis in particular. I hate noticing that it's...

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