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cypherpunk666

indeed, the ideas could be used more widely.

fil-c runs on linux.

what if linux ran on fil-c?

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Do you want your kernel to be 2x slower and use 4x as much memory?

A computer spends the vast majority of its time and memory in userspace, so this tradeoff isn't as bad as it sounds.

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.

a fun exercise is to ask an LLM how it might be applied.

You can run your Fil–C userland on provably–secure seL4.

(Left as an exercise for the reader)

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.

I was under the impression that fil-c's memory management (gc?) wouldn't work on a kernel? Be sweet if you could, ofc

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.

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?

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

what if fil-c could draw pelicans?

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