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Penultimate donut post: the function compute() is safe
Pascal Cuoq on 19 September 2011

Do two jobs, and do them well In the previous post, I used the command: $ cat log? | grep \N " | sort | uniq This may be an inefficient way to get a list of unique lines containing "N ". The command sort does not know that it...

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Probably safe donut
Pascal Cuoq on 17 September 2011

Introduction In the first post in the obfuscated animated donut series my colleague Anne pointed out that: The alarm about : assert \valid(". -~:;=!*#$@"+tmp_7); seems strange because the analysis tells us that tmp_7 ∈ [0..40] at this point... How can this be valid ? It is only safe to use...

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Safe donut
Pascal Cuoq on 16 September 2011

This post documents the steps I followed in order to finish verifying function compute(), picking up from there. Previously on this blog In last episode we had found that some sub-cubes in the search space appeared to lead to dangerous value sets for variable N. These sets were: N ∈...

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Trail
Pascal Cuoq on 16 September 2011

As I write these words, Virgile Prevosto, one of the dozen Frama-C developers, has been running 320km (starting last Sunday at 10am CET). He has about 12km left before he finishes the "Tor des Géants" endurance trail. That's TWO HUNDRED FULL-FLEDGED MILES in imperial units and I write this with...

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Big round number
Pascal Cuoq on 15 September 2011

The last post was the 64th in this blog. I just thought you should know that.

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