config-rs broken since rust 1.48

[dessalines]

We're trying to use config-rs using the latest rust nightly-1.49-0, and we're getting:

thread 'main' panicked at 'attempted to leave type `linked_hash_map::Node<std::string::String, value::Value>` uninitialized
, which is invalid', /home/tyler/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/
mem/mod.rs:659:9

I see this is also failing on your travis build too:

https://travis-ci.org/github/mehcode/config-rs/jobs/734764347#L291

cc @Nutomic

[joelgallant]

This is an upstream / rustc bug, no?

[dessalines]

Don't think so: https://travis-ci.org/github/mehcode/config-rs/jobs/734764347#L291

[dessalines]

config-rs is now broken on rust 1.48.0.

[joelgallant]

A quick note - this is a test failure, originating in serde_hjson. Error is bubbling up from this line.

[endeav0r]

This appears to be the offending line: https://github.com/contain-rs/linked-hash-map/blob/master/src/lib.rs#L174

linked-hash-map appears to be an old crate, with unsafe behavior. Allocated this type without initializing it, in this unsafe code, is what's throwing these errors. linked-hash-map is being used by yaml-rust, which is being used by config-rs. yaml-rust is maybe trying to replace linked-hash-map ( chyh1990/yaml-rust#157 ), which would most likely solve this issue.

Until then, I can't run my projects which rely on config-rs to parse yaml configurations :(.

[iruizr7]

This is happening now on last stable.

[martinellison]

I am getting this too.

[dessalines]

One possibility would be for config-rs to use feature flags, so that the upstream broken yaml-rust library can be ignored entirely.

[mehcode]

config does actually, except they're all by-default enabled

config = { version = "*", default-features = false, features = [ "json", "toml" ] }

[dessalines]

We are using config = { version = "0.10.1", default-features = false, features = ["hjson"] }, yet the build has still been failing since 1.48.0

[dessalines]

Since yaml-rust hasn't worked for the past two months, how about using https://github.com/dtolnay/serde-yaml as the yaml library instead?

[Nutomic]

We were wrong about this, the problem isnt caused by yaml-rust but by hjson-rust itself. Here is the issue with some possible solutions:

hjson/hjson-rust#23 (comment)

[dessalines]

Seems both libraries have the same ultimate problem: they're both using linked-hash-map, which is abandoned. They both need PRs to update to use the new https://github.com/kyren/hashlink library, which is maintained. Unfortunately yaml-rust's maintainers also seem to be unresponsive, as there's been a PR to merge hashlink that hasn't been looked at in months. Maybe hjson's maintainer will be more responsive.