Hoshino Lina (ζ˜ŸδΉƒγƒͺγƒŠ) 🩡 3D Yuri Wedding 2026!!!Mar 9

Out of curiosity, I wanted to see if ChatGPT noticed the bug/mistake I mentioned here:

https://github.com/obsproject/obs-studio/pull/13198#issuecomment-4019545931

I pasted the relevant function in and... it nitpicked all sorts of irrelevant stuff about error handling (allocation failures etc), types, and API contracts, and completely missed the actual issue. It even mentioned "the use of CLOEXEC is reasonable" and the fact it conflicts with some logic branches was completely missed.

This is a function using standard POSIX APIs. This isn't even obscure code, it's doing something (spawning a process with a pipe) that has been done a million times before.

It just didn't catch this bug because this bug / a similar shaped bug wasn't in its training data. Because AI isn't intelligent, it's still just fancy autocomplete and can't think.

("But you didn't catch it either" - I wasn't reviewing the whole function when I wrote that PR, I was fixing a different bug and had some tunnel vision since I was just normalizing/extending/fixing a pattern that was already there, so I didn't notice the use of CLOEXEC earlier. But I did ask ChatGPT to review the whole function, not just the PR change.)

Fix spurious fd closing (os_process and v4l2) by hoshinolina Β· Pull Request #13198 Β· obsproject/obs-studio

Description Fix two bugs causing the wrong file descriptors to be closed. The os_process one is harmless but was discovered while debugging this. The v4l2loopback one is actively causing crashes. M...

GitHub
Show threadHoshino Lina (ζ˜ŸδΉƒγƒͺγƒŠ) 🩡 3D Yuri Wedding 2026!!!Mar 9

Honestly it feels like AI is... something like optimizing for nitpicking "best practices" while completely missing the real issues.

Nobody writes code according to all "best practices". Error handling in the example above is an anti-pattern. This isn't a kernel. Littering your code with NULL checks for memory allocation (and functions which can only fail due to memory allocation failures behind the scenes, like fdopen) is a net negative because it achieves nothing (if small mallocs are failing you code is going to crash anyway) while making the code more obtuse and complex and hard to read, which means real bugs will slip through more often.

If you're the kind of person that cares about having more "strictly correct" code... you shouldn't be using C to begin with, but rather a language where doing that doesn't hurt readability (like Rust). But AI isn't going to give you that advice...

Show threadprincess pancake β€‹Mar 9
@lina you had me till the last paragraph

Not checking failures like that gives me such an overwhelming ick
Show threadHoshino Lina (ζ˜ŸδΉƒγƒͺγƒŠ) 🩡 3D Yuri Wedding 2026!!!

@natty Checking for memory allocation failure in a general purpose application is a waste of time. If allocations are failing, the only thing you can do is abort. Modern languages like Rust recognize this and default to making allocations panic, instead of forcing the programmer to handle it like a normal error. Even C++ does this with exceptions. Only in contexts like kernels and critical systems does it make sense to always handle allocations as fallible.

In C, letting the NULL deref crash is equivalent (and safe, NULL derefs are **not** a memory safety violation in practice, outside array indexing operations but we're talking about small object allocs with fixed size here). Sure you can check and explicitly abort... but that ends up being the same thing, just more code for no reason.

Every error check the LLM pointed out could only practically happen due to allocation failure.

Mar 9 at 3:37amWeb
Show threadprincess pancake β€‹Mar 9
@lina yeah I'm aware I'm just autistic af about the way I write code ​​
Show threadHoshino Lina (ζ˜ŸδΉƒγƒͺγƒŠ) 🩡 3D Yuri Wedding 2026!!!Mar 9
@natty I recommend Rust then ^^
Show threadCharlotte /Cinny     Mar 9
@lina @natty also due to overcommit the main time allocation fails is when you try to allocate stupendous amounts of memory, or if it is run under a specific, lower, memory limit
Show threadsarah tonin Mar 9
@charlotte @natty @lina unpopular oppinion: overcommit is a mistake and a security issue and shouldn't exist
Show threadsarah tonin Mar 9
@lina @natty lots of people make an xmalloc wrapper that just aborts on fail
Show threadHoshino Lina (ζ˜ŸδΉƒγƒͺγƒŠ) 🩡 3D Yuri Wedding 2026!!!Mar 9
@SRAZKVT @natty That doesn't help here, where the issue is standard POSIX functions that can only legitimately fail when internal memory allocations fail.
Show threadsarah tonin Mar 9
@lina @natty you make wrappers for those to ? sorry if i'm missing something
Show threadHoshino Lina (ζ˜ŸδΉƒγƒͺγƒŠ) 🩡 3D Yuri Wedding 2026!!!Mar 9
@SRAZKVT @natty I mean yeah but making infallible wrappers for every relevant C/posix function seems rather annoying
Show threadsarah tonin Mar 9
@lina @natty it's easier to handle than having everything abort by default when you need it to not
Show threadLisPiMar 9
@lina @natty If your runtime uses a memory cache it would make sense to handle it by clearing the cache & freeing the memory.

I'm thinking in particular of libc and the malloc cache.

But a lot of other VM-based languages make this a relevant consideration depending on configuration.