undefined | Better HN

0 pointsludocode1y ago0 comments

Oh, amazing! I've heard of DuskOS before but I didn't realize its C compiler was written in Forth.

Looks like it makes quite a few changes to C so it can't really run unmodified C code. I wonder how much work it would take to convert a full C compiler into something DuskCC can compile.

One of my goals with Onramp is to compile as much unmodified POSIX-style C code as possible without having to implement a full POSIX system. For example Onramp will never support a real fork() because the VM doesn't have virtual memory, but I do want to implement vfork() and exec().

0 comments

vdupras1y ago

It can't compile unmodified C code targeting POSIX. That's by design. Allowing this would import way too much complexity in the project.

But it does implement a fair chunk of C itself. The idea is to minimize the magnitude of the porting effort and make it mechanical.

For example, the driver the the DWC USB controller (the controller on the raspberry pi) comes from plan 9. There was a fair amount of porting to do, but it was mostly to remove the unnecessary hooks. The code itself, where the real logic happens, stays pretty much the same and can be compiled just fine by Dusk's C compiler.

j / k navigate · click thread line to collapse

0 comments

vdupras1y ago

It can't compile unmodified C code targeting POSIX. That's by design. Allowing this would import way too much complexity in the project.

But it does implement a fair chunk of C itself. The idea is to minimize the magnitude of the porting effort and make it mechanical.

j / k navigate · click thread line to collapse