Lorri doesn't build on unstable

[jpotier]

Describe the bug

Executing cargoBuildHook
++ env CC_x86_64-unknown-linux-gnu=/nix/store/xicw4xz0fnd9kmbdlnj6kajd4wz5im7l-gcc-wrapper-10.2.0/bin/cc CXX_x86_64-unknown-linux-gnu=/nix/store/xicw4xz0fnd9kmbdlnj6kajd4wz5im7l-gcc-wrapper-10.2.0/bin/c++ CC_x86_64-unknown-linux-gnu=/nix/store/xicw4xz0fnd9kmbdlnj6kajd4wz5im7l-gcc-wrapper-10.2.0/bin/cc CXX_x86_64-unknown-linux-gnu=/nix/store/xicw4xz0fnd9kmbdlnj6kajd4wz5im7l-gcc-wrapper-10.2.0/bin/c++ cargo build -j 16 --target x86_64-unknown-linux-gnu --frozen --release
   Compiling libc v0.2.86
   Compiling cfg-if v0.1.10
   Compiling proc-macro2 v1.0.18
   Compiling unicode-xid v0.2.0
   Compiling bitflags v1.2.1
   Compiling lazy_static v1.4.0
   Compiling getrandom v0.1.14
   Compiling syn v1.0.33
   Compiling autocfg v1.0.0
   Compiling maybe-uninit v2.0.0
   Compiling peg-runtime v0.6.2
   Compiling memchr v2.3.3
   Compiling proc-macro2 v0.4.30
   Compiling ppv-lite86 v0.2.8
   Compiling serde v1.0.114
   Compiling varlink_parser v4.0.4
   Compiling log v0.4.8
   Compiling cc v1.0.54
   Compiling unicode-xid v0.1.0
   Compiling chainerror v0.4.3
   Compiling remove_dir_all v0.5.3
error[E0119]: conflicting implementations of trait `std::error::Error` for type `&ChainError<_>`:
   --> /build/lorri-1.3.1-vendor.tar.gz/chainerror/src/lib.rs:493:1
    |
493 | impl<T: 'static + Display + Debug> Error for &ChainError<T> {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: conflicting implementation in crate `std`:
            - impl<'a, T> std::error::Error for &'a T
              where T: std::error::Error, T: ?Sized;

error: aborting due to previous error

For more information about this error, try `rustc --explain E0119`.
error: could not compile `chainerror`

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: build failed

To Reproduce Steps to reproduce the behavior:

1. clone nixpkgs at commit 9e377a6
2. nix build -I nixpkgs=. nixpkgs.lorri

Expected behavior Build goes through

Metadata

$ uname -a
Linux kktdr 5.11.0 #1-NixOS SMP Sun Feb 14 22:32:24 UTC 2021 x86_64 GNU/Linux

[iAmMrinal0]

A PR is open at https://github.com/NixOS/nixpkgs/pull/119114

[robintown]

Fixed in nixpkgs master, this can be closed.