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Comment by pjc50 | Hacker News Reader

I don't know where this got a downvote from because it's correct - it's quite hard to build sensible automatic integration tests for embedded code unless you have the luxury of a full system emulation.

The only thing that resource constraint forces is less code, especially less dependencies, because you run out of space.

The Toyota "unintended acceleration" court case was a flagship example of bad embedded code, that we rarely get to see.

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The Toyota computer is like a super computer compared to old mainframes. IIRC the Toyota program had 10k global variables updated by spaghetti C code. So you had a lot of space, enough to shoot yourself with C code. Old mainframe code in contrast often operated on records in a batch fashion, with a pretty clear input and output.

Of course, the antipattern on enterprise code comparable to thousands of global variables in C code, is to have thousands of columns in hundreds, or thousands even, of database tables, all intertwined and used only God knows where.

AFAIR, the were also autogenning code from a Matlab model of the engine, and that's where the 10k globals thing is from. Like yeah there's technically C code that's doing that, but come on.

Interesting, I thought the "unintended acceleration" was actually just floor mats creeping up and holding the accelerator pedal. Gonna have to google some stuff now :-)

https://news.ycombinator.com/item?id=9643204

It's one of those Rashomon situations where I'm not sure we can ever be entirely sure but it seems to have stopped.

Thank you for linking that. The comments in it share some terrifying stories.

That was Toyota's explanation for what was happening. Turned out to be a lie or a hasty conclusion, I don't remember which.

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