reqwest can not cross build for target x86_64-unknown-linux-musl with tokio library

[ikey4u]

This a minimal example to reproduce the problem.

• Cargo.toml

  [package]
  name = "reqwest-demo"
  version = "0.1.0"
  edition = "2021"
  
  [dependencies]
  reqwest = { version = "0.11.9", features = ["json", "multipart", "native-tls-vendored"] }
  tokio = { version = "1.0", features = [ "full" ] }
  

• main.rs

  #[tokio::main]
  async fn main() {
      let response = reqwest::Client::new()
          .post("http://www.baidu.com")
          .form(&[("one", "1")])
          .send()
          .await
          .expect("send");
      println!("Response status {}", response.status());
  }
  

Notice that reqwest enables feature native-tls-vendored to let us build tls library source using zig.

To build the example, using command below

cargo-zigbuild zigbuild --target x86_64-unknown-linux-musl

The generated error is here

ld.lld: error: undefined symbol: _$LT$libc..unix..linux_like..linux..musl..sigaction$u20$as$u20$core..clone..Clone$GT$::clone::h5d005990411f7b3b
      >>> referenced by lib.rs:196 (~/.cargo/registry/src/mirrors.tuna.tsinghua.edu.cn-df7c3c540f42cdbd/signal-hook-registry-1.4.0/src/lib.rs:196)
      >>>               signal_hook_registry-bdc7223cbb468750.signal_hook_registry.c6e8fee1-cgu.3.rcgu.o:(_$LT$signal_hook_registry..Prev$u20$as$u20$core..clone..Clone$GT$::clone::h3790061594f1b072)

And line 196 is here

[messense]

It could be something to do with this https://github.com/messense/cargo-zigbuild/blob/bdda6ef83937e57b99fa3a6c14d81ec95a97a290/src/zig.rs#L70-L81

[messense]

@ikey4u Are you using Rust 1.59.0, please try #12.

[ikey4u]

@messense yes, I use rust 1.59.0, and the build passed using the pr #12

[messense]

@ikey4u Thanks for confirming, I've also verified that the built artifact runs fine.

[ikey4u]

@messense Unfortunately, I test patch #12 with Rust 1.58.0, it does not work. The error is the same.

[messense]

That's unfortunate but this project is so young that I'm not aiming for supporting old Rust versions.

[ikey4u]

its does not matter, but you can specify the minimal supported rust version on homepage.

[messense]

For future reference, this issue is caused by upstream Rust distributes libc.a in self-contained for musl and wasi since Rust 1.59.0 (I think the code is in 1.58.0 but isn't really used since it requires a libc 0.2.107 and later).