Compiling rustler on Docker Alpine

[simonprev]

I’ve been trying to deploy an Elixir app with a rustler based module. Everything works fine in development but when I try to build the docker image on Alpine, I have this error:

Compiling NIF crate :nifty_graph (native/nifty_graph)...
    Updating crates.io index
    Updating git repository `https://github.com/rusterlium/rustler`
 Downloading crates ...
  Downloaded unreachable v1.0.0
  Downloaded quote v1.0.2
  Downloaded which v3.1.0
  Downloaded petgraph v0.5.0
  Downloaded heck v0.3.1
  Downloaded lazy_static v1.4.0
  Downloaded syn v1.0.13
  Downloaded proc-macro2 v1.0.7
  Downloaded indexmap v1.3.1
  Downloaded failure v0.1.6
  Downloaded fixedbitset v0.2.0
  Downloaded libc v0.2.66
  Downloaded unicode-xid v0.2.0
  Downloaded unicode-segmentation v1.6.0
  Downloaded void v1.0.2
  Downloaded autocfg v1.0.0
  Downloaded backtrace v0.3.42
  Downloaded rustc-demangle v0.1.16
  Downloaded cfg-if v0.1.10
  Downloaded backtrace-sys v0.1.32
  Downloaded cc v1.0.50
error: cannot produce dylib for `nifty_graph v0.1.0 (/build/native/nifty_graph)` as the target `x86_64-unknown-linux-musl` does not support these crate types
** (RuntimeError) Rust NIF compile error (rustc exit code 101)

This seems to be a known issue of Alpine, but can you guide me on possible solution on building a docker container with a rust dependency?

Thank you!

[gcauchon]

For what it’s worth, I created a simple repo to reproduce the issue…

https://github.com/gcauchon/rustler-alpine

That’s about as far as my rust skills can go!

[hansihe]

This seems to be the issue you are hitting rust-lang/cargo#7563

Does anything in there help?

[gcauchon]

Does anything in there help?

It did more than help; it fixed the issue: https://github.com/gcauchon/rustler-alpine#solution

🍻 @hansihe

[evnu]

To conclude, building on alpine works when build-base is installed and the target-feature=-crt-static flag is used:

RUSTFLAGS='--codegen target-feature=-crt-static'