Cargo.toml OS Dependency for Crate

Question

I have a rust project where i include the mysql-crate dependency and i want to have it os independent.

So i tried: Cargo.toml

[package]
name = "test"
version = "0.1.0"
authors = ["daMaex"]

[dependencies]
ws = "*"
clap = "*"
env_logger = "*"

[target.'cfg(any(unix, macos))'.dependencies.mysql]
version = "*"
default-features = false
features = ["socket"]

[target.'cfg(windows)'.dependencies.mysql]
version = "*"
default-features = false
features = ["pipe"]

[features]
default = []
ssl = []

The error already happens with a minimal main: src/main.rs

fn main () {
}

But the build fails. On macos/unix it always wants to compile the pipe and get's an unresolved import:

error[E0432]: unresolved import `std::os::windows::io::RawHandle`
  --> /home/user/.cargo/registry/src/github.com-1ecc6299db9ec823/named_pipe-0.2.2/src/lib.rs:38:5
   |
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Could not find `windows` in `std::os`

and the same happens on Windows for the mysql crate itself:

error[E0432]: unresolved import `std::os::unix`
  --> C:\Users\user\.cargo\registry\src\github.com-1ecc6299db9ec823\mysql-7.1.2\src\io.rs:24:5
   |
24 | use std::os::unix as unix;
   |     ^^^^^^^^^^^^^^^^^^^^^ no `unix` in `std::os`

So my question is, how do i handle the OS-Dependency in this case?

Answer 1

This looks like a cargo bug to me. One related issue is Cannot declare different version of dependencies in mutually exclusive targets #3195

Edit: It is more of an unsupported feature than a bug according to the code.