Slashdot Mirror
Lessons From Your Toughest Software Bugs
Nerval's Lobster writes: Most programmers experience some tough bugs in their careers, but only occasionally do they encounter something truly memorable. In developer David Bolton's new posting, he discusses the bugs that he still remembers years later. One messed up the figures for a day's worth of oil trading by $800 million. ('The code was correct, but the exception happened because a new financial instrument being traded had a zero value for "number of days," and nobody had told us,' he writes.) Another program kept shutting down because a professor working on the project decided to sneak in and do a little DIY coding. While care and testing can sometimes allow you to snuff out serious bugs before they occur, some truly spectacular ones occasionally end up in the release... despite your best efforts.
I once had a hiesenbug, which was a simple dereferrenced pointer. The problem is that I had a couple thousand lines of code, and the bug wasn't where I was recently coding. Every coder knows to check for bugs in their most recent code, but a derefferenced pointer can be anywhere in the code. Anyway, I decided to break down and pray for help. Then within moments I read through a random line of code in some random file and debugged the problem. Since then, I often pray I do well in general, then I don't get stuck on a brick wall of tech, that God helps me while I code, and a host of other cool stuff. I find things flow more smoothly since then and I don't fight with code. I know God is real, and I've come to discover prayer does help too. In addition to that, I've been more careful with pointer math, biasing array memory structures more.
God spoke to me
while (something) {
// do_stuff
} while (something_else);
It compiles, is legal C, and loops endlessly if something_else is true.
It can be done in a careless moment when switching a complex piece of code from a while () loop to a do-while () loop.
Well, next time write:
x = ++x;