Failing to build example.

[rvlander]

I have tried different way to build examples but without success.

The README page seems to be outdated.
I tried to directly cargo build in an example dir, but there is a compilation error when compiling core.

I tried to look to travis log to find a way: I have have another compilation error.

[posborne]

@rvlander What version of rust? Also, can you post the compilation error you are getting?

[rvlander]

@posborne, what method should I use? README based? Travis base? or cargo build in example directory?

I tried with rust nightly (1.4.0) and rust 1.3.0beta.

[posborne]

@rvlander, I apologize. It has been a little while since I have tried to build. I think there are a few things going on.

1. The README is wrong. This issue is covered by Fix makefile to build cargoized examples #333. Right now, you should be able to go into the example you want to bulid and just do a cargo build, I believe.
2. The build is failng on nightly due to fallout from RFC: Stabilize the #![no_std] attribute rust-lang/rfcs#1184. Changes upstream have caused extern create core to be included by default which is breaking compilation for several libs in zinc and rlibc.

I probably won't be able to get to making changes today, but I was able to reproduce a problem. Does this look like what you get when trying to compile an example?

$ cargo build
    Updating git repository `https://github.com/hackndev/rust-libcore`
    Updating git repository `https://github.com/hackndev/rlibc`
    Updating registry `https://github.com/rust-lang/crates.io-index`
   Compiling zinc v0.1.0 (file:///home/posborne/Projects/rust-playground/zinc/examples/blink_lpc17xx)
   Compiling core v1.0.0 (https://github.com/hackndev/rust-libcore#d9dc4f94)
   Compiling volatile_cell v1.0.0 (file:///home/posborne/Projects/rust-playground/zinc/examples/blink_lpc17xx)
   Compiling rlibc v0.1.3 (https://github.com/hackndev/rlibc?branch=zinc#0acbe22b)
/home/posborne/Projects/rust-playground/zinc/volatile_cell/lib.rs:21:1: 21:19 error: an external crate named `core` has already been imported into this module [E0259]
/home/posborne/Projects/rust-playground/zinc/volatile_cell/lib.rs:21 extern crate core;
                                                                     ^~~~~~~~~~~~~~~~~~
/home/posborne/Projects/rust-playground/zinc/volatile_cell/lib.rs:21:1: 21:19 help: run `rustc --explain E0259` to see a detailed explanation
error: aborting due to previous error
   Compiling syntaxext_lint v0.1.1
/home/posborne/.cargo/git/checkouts/rlibc-d63266f592a961ed/zinc/src/lib.rs:30:1: 30:19 error: an external crate named `core` has already been imported into this module [E0259]
/home/posborne/.cargo/git/checkouts/rlibc-d63266f592a961ed/zinc/src/lib.rs:30 extern crate core;
                                                                              ^~~~~~~~~~~~~~~~~~
/home/posborne/.cargo/git/checkouts/rlibc-d63266f592a961ed/zinc/src/lib.rs:30:1: 30:19 help: run `rustc --explain E0259` to see a detailed explanation
error: aborting due to previous error
   Compiling macro_zinc v0.1.0 (file:///home/posborne/Projects/rust-playground/zinc/examples/blink_lpc17xx)
Build failed, waiting for other jobs to finish...
Could not compile `volatile_cell`.

[rvlander]

Yes I have the same error.

[rvlander]

I have the following error now:

/home/gandre/.cargo/git/checkouts/rust-libcore-a3e1d25b35d5cd12/master/rust/src/libcore/lib.rs:123:9: 123:16 error: file for module prelude found at both prelude.rs and prelude/mod.rs
/home/gandre/.cargo/git/checkouts/rust-libcore-a3e1d25b35d5cd12/master/rust/src/libcore/lib.rs:123 pub mod prelude;
^~~~~~~
/home/gandre/.cargo/git/checkouts/rust-libcore-a3e1d25b35d5cd12/master/rust/src/libcore/lib.rs:123:9: 123:16 help: delete or rename one of them to remove the ambiguity

[mcoffin]

@rvlander That looks to be a problem upstream with the version of nightly rust that you're using, though I could be wrong.

[farcaller]

rust-libcore shouldn't fail to compile. can you please try with the next nightly and report back?

[rvlander]

I tested with rustc 1.4.0-nightly (e822a18ae 2015-08-16)

[posborne]

@rvlander, what specific command are you using to build? I have seen similar errors when I forget to add on the target spec.