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[return to "War story: the hardest bug I ever debugged"]
1. BobbyT+Hp7[view] [source] 2025-03-27 03:27:20
>>jakevo+(OP)
Interesting writeup, but 2 days to debug “the hardest bug ever”, while accurate, seems a bit overdone.

Though abs() returning negative numbers is hilarious.. “You had one job…”

To me, the hardest bugs are nearly irreproducible “Heisenbugs” that vanish when instrumentation is added.

I’m not just talking about concurrency issues either…

The kind of bug where a reproduction attempt takes a week, not parallelizable due to HW constraints, and logging instrumentation makes it go away or fail differently.

2 days is cute though.

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2. jakevo+bq7[view] [source] 2025-03-27 03:33:23
>>BobbyT+Hp7
Author here! I debugged a fair number of those when I was a systems engineer in soft real time robotics systems, but none of them felt as bad in retrospect because you're just reading up on the system and mulling over it and eventually you get the answer in a shower thought. Maybe I just find the puzzle of them fun, I don't know why they don't feel quite so bad. This was just an exhausting 2-day brute-force grind where it turned out the damn compiler was broken.
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3. gertle+0u7[view] [source] 2025-03-27 04:25:37
>>jakevo+bq7
I also came to the comments to weigh in on my perception of how rough this was, but instead will ask:

Regarding "exhausting 2-day brute-force grind": is/was this just how you like to get things done, or was there external pressure of the "don't work on anything else" sort? I've never worked at a large company, and lots of descriptions of the way things get done are pretty foreign to me :). I am also used to being able to say "this isn't getting figured out today; probably going to be best if I work on something else for a bit, and sleep on it, too".

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