can't find crate for `core`

[jesse99]

This error can happen when a crate depends upon another crate which depends upon a different version of a crate they both share. It's a very poor error message though because:

• It's misleading (the problem is that the crates were incompatible not that core could not be found: both versions of core were present).
• It doesn't provide any context. Which crates are involved? What are the version numbers of the incompatible crates?

One way to debug this is to do rustc --ls on each crate you depend upon and see if the common crate version numbers match up.

[catamorphism]

I agree this is really frustrating. Milestoning as 0.6, though others may disagree.

[nikomatsakis]

Not critical for 0.6; removing milestone

[catamorphism]

Nominating for milestone 5, production-ready

[graydon]

accepted for production-ready milestone

[graydon]

either diagnostics-related or possibly the "multiple versions of the same crate" functionality doesn't work transitively through dependencies.

[pnkfelix]

P-low, not 1.0 blocker. (Would nice to provide better diagnostics here though...)

[parkr]

I can't seem to compile anything at the moment, which is weird. Using rust as installed via Homebrew on the mac. No rustpkg installed.

~/code/snake.rs/ncurses-rs$ rustc --version
rustc 0.10
host: x86_64-apple-darwin

[thehydroimpulse]

@parkr You should probably hop on the IRC channel where there are people there to help sort out issues. It's recommended that you install the nightlies (i.e., from the rust website instead of brew) instead of 0.10 (which is pretty outdated by now). However, not all libraries are keeping up to the nightlies, so they may break.

[steveklabnik]

Can anyone provide a way to reproduce this kind of issue?

[steveklabnik]

Well, it's been a few months. With our current installers and such, I think we should try to handle specific instances of this issue, but I don't think that there's anything specifically actionable here.