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by cypherpunk666 4 days ago
indeed, the ideas could be used more widely.

fil-c runs on linux.

what if linux ran on fil-c?
3 comments
josephg 4 days ago
Do you want your kernel to be 2x slower and use 4x as much memory?
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wavemode 4 days ago
A computer spends the vast majority of its time and memory in userspace, so this tradeoff isn't as bad as it sounds.
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josephg 4 days ago
The benefit also isn’t as big as you might expect. Most of Linux’s recently found security vulnerabilities were due to ToC/ToU bugs. Fil-C would not magically fix these problems.

It would sometimes be a good trade off, for some users. But I don’t think many regular users would choose to pay this cost.

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cypherpunk666 4 days ago
a fun exercise is to ask an LLM how it might be applied.
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avadodin 4 days ago
You can run your Fil–C userland on provably–secure seL4.

(Left as an exercise for the reader)

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josephg 4 days ago
If you’re using SeL4, userland processes are already strictly sandboxed. There’s still some benefit to Fil-C, since the added memory safety would make it much more difficult to take over a process. But the blast radius of a compromised program in SeL4 is much smaller because of the capability model.
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yjftsjthsd-h 4 days ago
I was under the impression that fil-c's memory management (gc?) wouldn't work on a kernel? Be sweet if you could, ofc
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brabel 4 days ago
This is a myth that seems to never die. OS kernels can and have been written in GC languages. Watch the video maybe? The whole presentation was running on a distro fully compiled with FillC.
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yjftsjthsd-h 3 days ago
The video has a slide which says,

> I'm running on an OS where the entire userland is compiled with Fil-C/C++

(emphasis mine)

Looking up https://fil-c.org/pizlix , that says,

> The kernel is compiled with Yolo-C. So that you can compile the kernel, a copy of GCC is installed in /yolo/bin/gcc.

Where do you see anything saying the Linux (the kernel) can be built with Fil-C?

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brabel 3 days ago
Ok, I stand corrected: only the kernel userland was compiled with Fil-C.

However, I don't see why the full Linux kernel could not be compiled with Fil-C. It would be nice if Fil himself could explain what limitations there are, but the documentation does not list missing C/C++ features as far as I know, it only says it's "fanatically compatible" which I take to mean mostly everything should work?!

But to my point in general, here's a osdev.org wiki explaining how high level languages can and have been used for OS development (with the caveat that some Assembly code is required, which I believe is also true of kernels written in C): https://wiki.osdev.org/Languages

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doctorpangloss 4 days ago
what if fil-c could draw pelicans?
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