#![no_std] with WASI is more complicated than I thought it would be

• cargo-wasi

  2 439 3.3 Rust

  A lightweight Cargo subcommand to build Rust code for the `wasm32-wasi` target

  

I use cargo-wasi to build it:

• wasi-libc

  48 797 7.7 C

  WASI libc implementation for WebAssembly

  

So what happened is that _start is already defined by this mysterious crt1-command.o. I didn't learn until much after that this is from wasi-libc:

• InfluxDB

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  Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.

  

• WASI

  45 4,582 7.0 Rust

  WebAssembly System Interface

  

Uh... ok then. At this point I decide that I should probably use WASI to define this exit function, instead of just endlessly looping. So I link in proc_exit. According to the WASI docs, proc_exit takes in an exitcode (a u32) and returns nothing. Perfect!

• wasi

  1 230 6.3 Rust

  Experimental WASI API bindings for Rust (by bytecodealliance)

  

At this point, I look into Bytecode Alliance's WASI rust bindings, used by Rust's std.

• wasmtime

  172 14,461 10.0 Rust

  A fast and secure runtime for WebAssembly

  

I use fd_write, and since I don't want to look into how interface types work, I just look at the wasi crate again, with some help from the wasmtime WASI WAT tutorial.

• wee_alloc

  7 632 0.0 Rust

  The Wasm-Enabled, Elfin Allocator

  

Ok. Now I need to add in a global allocator. I use wee_alloc since I know it works pretty well with WASM: Cargo.toml

• compiler-builtins

  12 339 7.8 Rust

  Porting `compiler-rt` intrinsics to Rust

  

Um. Ok, I remember this kind of thing. I do some searching and then rediscover compiler_builtins.

• WorkOS

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