Allow lang and lib features to share names

[varkor]

Fixes#58715.

I didn't add a test, because there's currently no standard lang test feature and I felt apprehensive about adding a permanently unstable feature. Instead, a shared lang/lib feature will be used in #57760 and will essentially provide an immediately test.

[rust-highfive]

r? @davidtwco

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[alexreg]

Looks good!

@bors r=alexreg

[bors]

📌 Commit 0f6b148 has been approved by alexreg

[alexreg]

@bors p=1 (So that this can land ahead of #57760 (comment) when we r+ p=1 that again.)

[bors]

📌 Commit 0f6b148 has been approved by alexreg

[Centril]

r? @alexreg

[petrochenkov]

I think I have deja vu.
This was already fixed last year, and that made features like proc_macro available for both the language and the library?

[bors]

⌛ Testing commit 0f6b148 with merge 4aedbcf6ac902f3c2e395c68fa8f752dd6a13908...

[bors]

💔 Test failed - checks-travis

[rust-highfive]

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

Attempting to download s3://rust-lang-ci-sccache2/docker/6cac209d48f799e2dc88d5e1c18094107562ae9c4d43ec184562faf579272168f32666b034cfb32f496a69191ed27258c81ab3632fc655326f9b2763ccb61350
[00:00:11] Attempting with retry: curl -y 30 -Y 10 --connect-timeout 30 -f -L -C - -o /tmp/rustci_docker_cache https://s3-us-west-1.amazonaws.com/rust-lang-ci-sccache2/docker/6cac209d48f799e2dc88d5e1c18094107562ae9c4d43ec184562faf579272168f32666b034cfb32f496a69191ed27258c81ab3632fc655326f9b2763ccb61350
[00:00:11] % Total % Received % Xferd Average Speed Time Time Time Current
[00:00:11] Dload Upload Total Spent Left Speed
No output has been received in the last 30m0s, this potentially indicates a stalled build or something wrong with the build itself.
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The build has been terminated

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[varkor]

@bors retry

[varkor]

This was already fixed last year, and that made features like proc_macro available for both the language and the library?

Interesting. Maybe this sneaked in with more recent refactorings in the last year? Although I haven't seen any regressions relating to this. I'm not sure...

[bors]

⌛ Testing commit 0f6b148 with merge 37ab9096515882ae082629b25091e4a6e750a88e...

[bors]

💔 Test failed - checks-travis

[rust-highfive]

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

Attempting to download s3://rust-lang-ci-sccache2/docker/7e1a0f6dbf7ee5eb0f689d3f3f0b0c18b1a9c99aaacc2a649ce33a6db602dde1d880b783741255f4fb7da1afa8a7b1e7897822d59f692a8c90e11f791375e7c7
[00:00:25] Attempting with retry: curl -y 30 -Y 10 --connect-timeout 30 -f -L -C - -o /tmp/rustci_docker_cache https://s3-us-west-1.amazonaws.com/rust-lang-ci-sccache2/docker/7e1a0f6dbf7ee5eb0f689d3f3f0b0c18b1a9c99aaacc2a649ce33a6db602dde1d880b783741255f4fb7da1afa8a7b1e7897822d59f692a8c90e11f791375e7c7
[00:00:25] % Total % Received % Xferd Average Speed Time Time Time Current
[00:00:25] Dload Upload Total Spent Left Speed
No output has been received in the last 30m0s, this potentially indicates a stalled build or something wrong with the build itself.
Check the details on how to adjust your build configuration on: https://docs.travis-ci.com/user/common-build-problems/#Build-times-out-because-no-output-was-received
The build has been terminated

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[alexreg]

@petrochenkov Well, the evidence says otherwise...?

[alexreg]

@bors retry

[bors]

⌛ Testing commit 0f6b148 with merge 4855370...

[bors]

☀️ Test successful - checks-travis, status-appveyor
Approved by: alexreg
Pushing 4855370 to master...