error[E0523]: found two different crates with name `std` that are not distinguished by differing `-C metadata`. This will result in symbol conflicts between the two.

[sanderjo]

Trying to build with cargo build --release I get:

   Compiling clap v2.24.2
   Compiling scroll_derive v0.4.0
error[E0523]: found two different crates with name `std` that are not distinguished by differing `-C metadata`. This will result in symbol conflicts between the two.
 --> /home/sander/.cargo/registry/src/github.com-1ecc6299db9ec823/scroll_derive-0.4.0/src/lib.rs:3:1
  |
3 | extern crate proc_macro;
  | ^^^^^^^^^^^^^^^^^^^^^^^^

error: Could not compile `scroll_derive`.
Build failed, waiting for other jobs to finish...
error: build failed
sander@Stream-13:~/git/bingrep$

Version of rustc:

sander@Stream-13:~$ rustc --version
rustc 1.16.0

This is on Ubuntu 17.04

Full log of CLI:

sander@Stream-13:~/git$ rm -rf bingrep/
sander@Stream-13:~/git$ rm -rf /home/sander/.cargo/

sander@Stream-13:~/git$ git clone https://github.com/m4b/bingrep.git
Cloning into 'bingrep'...
remote: Counting objects: 91, done.
remote: Compressing objects: 100% (12/12), done.
remote: Total 91 (delta 6), reused 15 (delta 5), pack-reused 73
Unpacking objects: 100% (91/91), done.
sander@Stream-13:~/git$ cd bingrep/

sander@Stream-13:~/git/bingrep$ cargo build --release
    Updating registry `https://github.com/rust-lang/crates.io-index`
 Downloading colored v1.5.1
 Downloading goblin v0.0.10
 Downloading structopt v0.0.3
 Downloading structopt-derive v0.0.3
 Downloading lazy_static v0.2.8
 Downloading plain v0.0.2
 Downloading scroll v0.5.0
 Downloading scroll_derive v0.4.0
 Downloading quote v0.3.15
 Downloading syn v0.11.11
 Downloading synom v0.11.3
 Downloading unicode-xid v0.0.4
 Downloading clap v2.24.2
 Downloading vec_map v0.8.0
 Downloading unicode-width v0.1.4
 Downloading strsim v0.6.0
 Downloading bitflags v0.8.2
 Downloading atty v0.2.2
 Downloading ansi_term v0.9.0
 Downloading unicode-segmentation v1.2.0
 Downloading term_size v0.3.0
 Downloading libc v0.2.23
   Compiling scroll v0.5.0
   Compiling unicode-xid v0.0.4
   Compiling unicode-segmentation v1.2.0
   Compiling ansi_term v0.9.0
   Compiling strsim v0.6.0
   Compiling unicode-width v0.1.4
   Compiling quote v0.3.15
   Compiling synom v0.11.3
   Compiling libc v0.2.23
   Compiling plain v0.0.2
   Compiling lazy_static v0.2.8
   Compiling colored v1.5.1
   Compiling atty v0.2.2
   Compiling syn v0.11.11
   Compiling bitflags v0.8.2
   Compiling vec_map v0.8.0
   Compiling term_size v0.3.0
   Compiling clap v2.24.2
   Compiling scroll_derive v0.4.0
error[E0523]: found two different crates with name `std` that are not distinguished by differing `-C metadata`. This will result in symbol conflicts between the two.
 --> /home/sander/.cargo/registry/src/github.com-1ecc6299db9ec823/scroll_derive-0.4.0/src/lib.rs:3:1
  |
3 | extern crate proc_macro;
  | ^^^^^^^^^^^^^^^^^^^^^^^^

error: Could not compile `scroll_derive`.
Build failed, waiting for other jobs to finish...
error: build failed
sander@Stream-13:~/git/bingrep$ 

[sanderjo]

Related to rust-lang/rust#35636 (comment) ?

Three-line rust source file:

sander@Stream-13:~$ cat test.rs 

#![feature(rustc_private)]
extern crate flate;
fn main() {}

Building results in the same(?) error message:

sander@Stream-13:~$ rustc test.rs 
error[E0523]: found two different crates with name `std` that are not distinguished by differing `-C metadata`. This will result in symbol conflicts between the two.
 --> test.rs:2:1
  |
2 | extern crate flate;
  | ^^^^^^^^^^^^^^^^^^^

So assuming this is valid Rust code (I don't know), the problem is in the rust version on my Ubuntu?

[sanderjo]

Update:

Short: I got it working with the current Rust version 1.18.0

Long:

I removed Ubuntu's cargo, and did an install from the website:

curl https://sh.rustup.rs -sSf | sh
source $HOME/.cargo/env

Version:

$ rustc --version
rustc 1.18.0 (03fc9d622 2017-06-06)

And now the build is OK:

sander@Stream-13:~/git/bingrep$ cargo build --release
   Compiling unicode-segmentation v1.2.0
   Compiling plain v0.0.2
   Compiling bitflags v0.8.2
   Compiling lazy_static v0.2.8
   Compiling scroll v0.5.0
   Compiling ansi_term v0.9.0
   Compiling unicode-width v0.1.4
   Compiling unicode-xid v0.0.4
   Compiling synom v0.11.3
   Compiling strsim v0.6.0
   Compiling vec_map v0.8.0
   Compiling quote v0.3.15
   Compiling libc v0.2.23
   Compiling syn v0.11.11
   Compiling atty v0.2.2
   Compiling term_size v0.3.0
   Compiling clap v2.24.2
   Compiling structopt-derive v0.0.3
   Compiling scroll_derive v0.4.0
   Compiling goblin v0.0.10
   Compiling colored v1.5.1
   Compiling structopt v0.0.3
   Compiling bingrep v0.1.0 (file:///home/sander/git/bingrep)
    Finished release [optimized] target(s) in 213.67 secs
sander@Stream-13:~/git/bingrep$ 

... and bingrep is working. Cool!