compiler_builtins fails to compile due to using recently stabilized cfg_target_vendor

[mister-walter]

I'm not sure if this belongs here or on the main avr-rust/rust repo, but just wanted to post this here in case it's helpful to anyone else.

I'm using Xargo on Arch Linux with the latest commit of the avr-rust/rust master branch.

I managed to get past avr-rust/rust-legacy-fork#128 using hercek's patches, but building compiler_builtins failed because of a use of the cfg_config_vendor feature. That feature was stabilized earlier this year, but the it looks like the AVR patched Rust version hasn't pulled upstream since the stabilization.

To fix this, I simply modified the downloaded source for lib.rs in compiler_builtins in the Cargo registry folder (~/.cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.12/src/lib.rs on my machine), adding the missing #![feature(cfg_target_vendor)] line to the existing feature flags in that file.

I also get a message that indicates that it might be possible to set a version for compiler_builtins, though I wasn't able to figure out how:
warning: dependency (compiler_builtins) specified without providing a local path, Git repository, or version to use. This will be considered an error in future versions

The last version of compiler_builtins that has the cfg_target_vendor feature flag appears to be 0.1.5. (relevant commit)

More version info:

$ rustup run avr-toolchain xargo -V
xargo 0.3.14
cargo 1.36.0-nightly (6be12653d 2019-04-19)

$ rustup run avr-toolchain rustc -V
rustc 1.33.0-dev

[Rahix]

I was able to get it working by creating a Xargo.toml with the following contents:

[dependencies.core]
stage = 0

[dependencies.compiler_builtins]
stage = 1
version = "= 0.1.3"

[dylanmckay]

I guess this would be fixed by avr-rust/rust-legacy-fork#137

[Rahix]

Yes, I believe so. Any rough estimate, when that update is going to hit? / Is there a list of blocking issues that still need work?

[dylanmckay]

At the moment, the only issue blocking the merge is this bug

LLVM ERROR: Cannot select: t2: i16 = addrspacecast[1 -> 0] undef:i16

mentioned in this comment.

[stappersg]

At the moment, the only issue blocking the merge is this bug

LLVM ERROR: Cannot select: t2: i16 = addrspacecast[1 -> 0] undef:i16

mentioned in this comment.

That merge did happen.
Closing this issue about xargo. Lots of things changed since the opening of this issue.