SecurityNow on Randomness

Episodes 299 and 301 of the SecurityNow podcast deal with the problem of how to get randomness out of a computer. As usual, Steve Gibson does a good job of explaining things, but I felt that there was some more that needed to be said about computers and randomness, as well as the related ideas of predictability, observability, repeatability, and determinism. I have worked and wrangled with these concepts for almost 15 years now, from my research into timing prediction for embedded processors to my current work with the repeatable and reversible Simics simulator.

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Disappointing SystemC Debugger Integration Paper

Since I have a certain interest in debugging, I was happy find the article “Guidelines for SystemC – Debugger Integration” at the usually interesting Design and Reuse website. However, I must say that it was pretty disappointing.

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S4D 2011 Submission Time

The submissions for S4D 2011 is now open, at I have been to S4D for two years now, and I find it one of the most interesting conferences around. It is a nice mix of hardware design and software tools, all directed at the fundamental problem of how to debug a digital system. To me, it is the “debug conference” par excellence.

If you have something interesting to submit, please do. I won’t have time myself to write something for this year, unfortunately.

Software is Concrete – is it?

I this quote:

Software is Concrete. Once poured it becomes extremely difficult and very expensive to change.

It comes from a blog post by Robert Howe, CEO of Verum, a company selling formal-methods-based and model-based programming tools. It does capture something of the phenomenon we all know: that software can be pretty darn hard to change, once it has shipped and is in use. It fits well with the fact that the later bugs are found, the more expensive they are to fix.

But it also provoked quite a bit of opposition when I put the quote up on Facebook, and I have to agree that maybe not all is as simple as that blog makes it out to be.

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msys git – error could not allocate cygwin heap

I am using TortoiseGit on Windows for a while now, and it works OK. However, today, it just stopped working. The error I got persistently was:

0 [main] us 0 init_cheap: VirtualAlloc pointer is null, 
Win32 error 487 AllocationBase 0x0, BaseAddress 0x68540000, 
RegionSize 0x480000, State 0x10000 
*** Couldn't reserve space for cygwin's heap, Win32 error 0

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