

Debugging with Hypotheses - nkurz
http://ayronwohletz.com/debugging-with-hypotheses/

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greenyoda
_" Again, do not fix if you do not understand."_

I think that's the most important point of the article. If you don't
understand the code you're fixing well enough to be able to explain what the
bug does or why your fix fixed it, you'll have no way of knowing that (1) the
bug (and not just a particular limited case of it) is actually fixed and (2)
that you haven't introduced additional bugs by fixing the first one.

If you're reviewing someone's code and they can't explain to you how their fix
removed the bug (e.g., they just changed random stuff around and the bug "went
away"), that's a bad sign.

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petercooper
_In sleep, your “background mind” will process all the information you have
gathered. I often find that when I come back to the problem the next day the
solution jumps out at me._

This happened to me so often and in such striking ways that when presented
with a problem now, unless the answer is obvious, I always say I'll be
sleeping on it and, no, I won't be solving it today - it's interesting how
many people think this is laziness at first, and will even tell you so, but
are then thankful the next day when you come up with a creative solution.

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khuey
Andreas Zeller's Why Programs Fail is an excellent read for anyone who wants
to learn to debug rigorously.

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phkahler
I once asked someone "how is this function used?" He put a breakpoint in it,
ran the code, triggered it, and showed me a stack trace. "Here's how it's
called." That was a nice specific example, but I wanted an understanding of
intent or architecture or something he clearly didn't have. I almost never use
a debugger, but my approach was developed in a time of 8-bit machines that
didn't have debuggers. That said, I have seen bugs that could probably not be
found without a debugger - including compiler errors.

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t__crayford
Nice! I wholeheartedly agree - even so much I wrote a thing about this a while
back: [http://yellerapp.com/posts/2014-08-11-scientific-
debugging.h...](http://yellerapp.com/posts/2014-08-11-scientific-
debugging.html)

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zanethomas
The science of debugging. :)

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amelius
Actually, security hackers often write scientific papers about bugs :)

