low level bugs
In its first draft, a new feature in Steamhammer caused a crashing bug. After several runs to collect information, it looked like a bad pointer or a memory corruption bug. Thank you C++, we enjoy unsafe languages above all others. With more poking, I identified a memory safety issue and realized that it would take some rejiggering to fix. It took me several hours to do minor rewrites up and down long call chains and verify that I hadn’t missed any links. Finally the code was tight, everything was double-checked, it compiled correctly, and I ran the first test—and it failed with the exact same symptoms. It happens to everyone, right?
Well, the show must go on. I configured tests to all run on one map for efficient debugging, and brought out the loupe for a close look. It took me three days, I wrote self-test code to catch errors as early as possible and extract their secrets, I had to learn (what seems to me) Lovecraftian C++ arcana that I would prefer not to know the existence of much less to understand, but I solved it, and kept the code nice and efficient too, and my new feature came to work perfectly on the test map in a wide variety of situations. That took a lot longer than writing the first draft. OK, now to test more widely. On the very next map—the self-test immediately caught errors. It happens to everyone, right? Right? Right? Cue “They’re Coming to Take Me Away, Ha Ha!”
This bug turned out to be trivial, though.
I once worked with an intern who wrote the worst code I have ever seen. Not only was it tangled and barely decipherable, it was ingeniously self-modifying, and not with address variables but with hardcoded address constants so that it depended on running at a fixed address... even though the software was planned to be burned into ROM. Unbelievable but true. My first step in fixing it was to throw it out. I guess I should be proud of myself as a stable and careful programmer, since I still have some hair and I rarely lose days of time to low-level bugs.
But I have to say, if I wanted to have fun in an unsafe low-level language, I would use a fun unsafe low-level language, like FORTH.
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