rand_core 0.4.2 (backports)

[dhardy]

As requested in #783.

Note @gnzlbg this does not include the links attribute we discussed yesterday (#850), because I don't believe this is the best fix.

[gnzlbg]

The links attribute is a super strong hammer. There are ways to relax it a bit, but those are super hacky. So it should only really be used if there is absolutely no way for two crates to ever be part of the same dependency graph correctly (e.g. when linking a C library).

[vks]

There is also 90501dc, but this would have to be backported to rand 0.6.

[vks]

Why are the CI tests not running for this branch? Otherwise it looks fine to me.

[dhardy]

That may be because I originally opened it vs the wrong branch... think I'll have to close this and re-open.

[vks]

The failure in the average crate is weird. The crate should not use the serde1 feature.

[dhardy]

Yes indeed. It's clear from the macro expansion that the compiler is referring to features behind that feature flag:

10  | |      [cfg_attr (feature = "serde1" , derive (Serialize , Deserialize))] pub
    | |                                                          ^^^^^^^^^^^

It's clear from cargo tree --features=serde1,log that there is only a single dependency on average, which from the Cargo.toml never specifies any feature flags.

😕

[dhardy]

The define_histogram macro is defined here. @vks macros generate source code, hence that cfg(feature = "serde1") check only happens when instantiated inside the uniformity example.

I think therefore your macro is incorrect. Maybe the easiest solution would be to put the serde1 cfg outside the macro definition, and list both versions.

Inside rand, the serde1 feature we just tested only passes this feature to sub-crates, but doesn't do anything itself (thus the required serde libs are not linked). So I guess the solution is we shouldn't test rand with this feature active.

[vks]

I think therefore your macro is incorrect. Maybe the easiest solution would be to put the serde1 cfg outside the macro definition, and list both versions.

I just published average 0.10.2, hopefully fixing this bug by conditionally defining different macros.

You workaround was not complete, it seems cargo test --all-features is still executed.

[dhardy]

Thanks. Then I'll bump the required version of average since removing --all-features tests might have unintended consequences.

I'll be away for a few days, so if I don't get this published I go then hopefully you can.

[dhardy]

Now the 1.22 builder fails. I'd prefer not to bump the Rustc version for this release, so I guess the other solution is needed.

[vks]

Now the 1.22 builder fails.

Sorry about that, I have been following the minimal Rust version of Rand. However, it seems that disabling the serde tests worked.

[dhardy]

I forgot, we already pushed (and yanked) 0.4.1. I just bumped the version to 0.4.2 on master but publishing fails:

Caused by:
  patch for `rand_core` in `https://github.com/rust-lang/crates.io-index` did not resolve to any crates. If this is unexpected, you may wish to consult: https://github.com/rust-lang/cargo/issues/4678

Unfortunately I don't have time to look into this now.

[dhardy]

Published