NixOS beginner here. I need to build a Rust crate (https://github.com/paritytech/substrate-contracts-node) that depends on Clang.

I keep running into:

I've tried adding some packages to Home Manager (libclang, llvmPackages.libclang, clang), without success.

I also did a brief google search but I'm quite confused about how to go about this.

NixOS beginner here. I need to build a Rust crate (https://github.com/paritytech/substrate-contracts-node) that depends on Clang.

I keep running into:

thread 'main' panicked at 'Unable to find libclang: "couldn't find any valid shared libraries matching: ['libclang.so', 'libclang-*.so', 'libclang.so.*', 'libclang-*.so.*'], set the `LIBCLANG_PATH` environment variable to a path where one of these files can be found (invalid: [])"', /home/bear/.cargo/registry/src/github.com-1ecc6299db9ec823/bindgen-0.59.2/src/lib.rs:2144:31

I've tried adding some packages to Home Manager (libclang, llvmPackages.libclang, clang), without success.

I also did a brief google search but I'm quite confused about how to go about this.

In reply to @mikroskeem:d0.ee
LIBCLANG_PATH = "${llvmPackages.libclang.lib}/lib";

In reply to @bernardo:matrix.parity.io
I saw this suggestion during my Google search, but I couldn't figure out which file to add this line to. I tried adding it to the same file where my Home Manager definitions are with no success.

I'm using this shell.nix: https://github.com/paritytech/substrate/blob/master/shell.nix

applied at the root of this project: https://github.com/paritytech/substrate-contracts-node

I executed $ nix-shell then $ cargo build --release

and now I'm running into:

error[E0658]: use of unstable library feature 'proc_macro_is_available'

I'm guessing there's something missing on the shell.nix file?

In reply to @zhaofeng:zhaofeng.li
What does rustc --version show?

In reply to @zhaofeng:zhaofeng.li
What does rustc --version show?

In reply to @zhaofeng:zhaofeng.li
Hmm, that feature should exist in that version of nightly (it was removed a month later, which should cause it to complain that the feature is non-existent). Where is that in the code?

error[E0658]: use of unstable library feature 'proc_macro_is_available'
  --> /home/bear/.cargo/registry/src/github.com-1ecc6299db9ec823/proc-macro2-1.0.36/src/detection.rs:28:21
   |
28 |     let available = proc_macro::is_available();
   |                     ^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #71436 <https://github.com/rust-lang/rust/issues/71436> for more information
   = help: add `#![feature(proc_macro_is_available)]` to the crate attributes to enable