compiler-builtins VS rustix

I don't know which symbols are missing, haven't done anything on the llvm level. But I had the same problems creating a no-std no-libc application, if you add https://github.com/rust-lang/compiler-builtins as a dependency you should get all the symbols you need, std uses the same but if you want to use it outside of std you'll need nightly since it uses a lot a nightly features. It might apply to your case as well.

Ah, I see - you might be hitting https://github.com/rust-lang/compiler-builtins/issues/347.

There's a PR to the compiler-builtins crate which the rust implementation is based on.

I'm glad to inform y'all that after a year, the infamous LLVM ERROR: Not supported instr bug¹ has been finally fixed and today's nightly can compile for AVR back again! 😎

Then, some of the non-trivial things that are needed are already implemented and maintained in other crates, like memcpy and friends in compiler-builtins, all the math routines in libm and malloc in dlmalloc.

3.Use scons to compile, if errors jumped on link up, find the solution on its official Github.

It would be great for Rust to have a Linux target that doesn't use libc, but from what I've read, not many people are interested in this.

Found this as well: https://github.com/sunfishcode/mustang

Some discussion here: https://github.com/bytecodealliance/rustix/issues/76

Without actually having looked into this, how does https://github.com/bytecodealliance/rustix fit into points 1 & 2?

I find this github issue: https://github.com/bytecodealliance/rustix/issues/575

Hi Rust experts, we are willing to integrate rustix on NuttX RTOS, the initial effort was done by rustix author: https://github.com/bytecodealliance/rustix/tree/nuttx but it hit the wall since we don't know the right way to integrate cargo with the old-school NuttX's Makefiles. Any help or suggestion is welcome. More about NuttX here: https://nuttx.apache.org and here: https://nuttx.apache.org/docs/latest/

Have you considered using rustix? It provides many of the facilities of std without using libc.

rustix can make syscalls directly to Linux. There's a rustc fork that can use it to build std.

The rustix project claims to use raw syscalls (and vDSO calls) on linux and provides more memory / type safety compared to the libc API.

Hi, the reason is explained by the description of https://github.com/bytecodealliance/rustix.

Please consider rustix as an alternative to nix.