Hacker News Reader

Hacker News

Comment by mmastrac | Hacker News Reader

Parent Full thread

mmastrac

This is pretty wild. I hadn't realized that there were easy ways to work with EFI in higher-level languages than C.

Other languages:

Rust: https://medium.com/@gil0mendes/an-efi-app-a-bit-rusty-82c36b...

Wasn't able to find an example for Go, but seems likely it's out there.

View on HN

C# is higher-level in aggregate, but if you look at individual features, it lets you go as low as C in most respects - raw pointers with arithmetic, unions, stack allocations, you name it. It seems that this EFI project uses it at that level, and higher-level features that would require e.g. GC aren't supported.

This is one of the benefits of C# that makes it approachable to beginners.

I wouldn't say pointers and unsafe code are features that makes it approachable to beginners.

C# with boatloads of `unsafe` is by no means an higher level language; it's pretty much the same level of C/C++ or Rust. You're just using a more sophisticated complier and a stricter language, which can be great if used correctly, but if you dereference a null pointer, it's still going to crash and burn; this also applies to unsafe Rust.

Following the footsteps of system languages like PL/S or Mesa/Cedar, just to cite two quite old examples.

The good part is that the unsafe bits can be easily constrained, instead of hidding away in every single line of code.

> Wasn't able to find an example for Go, but seems likely it's out there.

NERF/LinuxBoot has a lot of Go components though as I remember it the EFI application is actually the Linux kernel, with the userland (i.e. init) being written in Go.

The kexec paradigm makes this execution vector rather more useful than most people realize. It's also what powers inline kernel crash dumps.

Go has segmented stacks, which could make it awkward to use in a bare-metal environment like this. I’m sure it’s possible, but it might be quite tedious to get working.

Go previously used segmented stacks, but stopped in the 1.4 release (2014)

How do they handle growing tons of stacks now?

Goroutine stacks start out small (2KB), are heap-allocated and copyable (unlike most Go memory).

Reply on news.ycombinator.com