The Underhanded C Contest

Discussion (7 Comments)Read Original on HackerNews

BiraIgnacio•about 3 hours ago

> The contest was initially inspired by Daniel Horn’s Obfuscated V contest in the fall of 2004 (note: the original page is long gone, and this link goes to a snapshot from archive.org). The object of that contest was to write a simple program to count votes, that somehow miscounts the votes on election day. I was greatly impressed to see how even a short program to simply count characters in a text file can be made to fail, and fail only on one specific day, so that the bug isn't noticed in testing.

https://underhanded-c.org/_page_id_7.html

silisili•about 2 hours ago

The original page actually loads fine, maybe was restored later?

I looked through a few trying not to read the short description and missed a lot of simple things, really makes you think...

https://graphics.stanford.edu/~danielh/vote/vote.html

AmazingEveryDay•about 5 hours ago

(2015). RIP.

gwern•about 5 hours ago

At least we still have https://www.ioccc.org/2025/index.html#inventory !

TZubiri•about 4 hours ago

2026 calls for an Underhanded prompt contest

theteapot•about 3 hours ago

Or better, sleeper agents. Anthropic released a study on this in 2024 "Sleeper Agents: Training Deceptive LLMs that Persist Through Safety Training" -- https://www.anthropic.com/research/sleeper-agents-training-d..., https://www.youtube.com/watch?v=_y9j2BoHg2c

pseudohadamard•25 minutes ago

Interesting that the case they were using was the Nuclear Threat Initiative and FP uncertainties, I've audited some, ah, nuclear-physics-related code that had an issue due to FP uncertainties...

The Underhanded C Contest

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Discussion (7 Comments)Read Original on HackerNews