Dual proc macro hash

[msizanoen1]

This PR changes current -Z dual-proc-macro mechanism from resolving only by name to including the hash of the host crate inside the transistive dependency information to prevent name conflicts.
Fix partially #62558

[rust-highfive]

r? @zackmdavis

(rust_highfive has picked a reviewer for you, use r? to override)

[msizanoen1]

r? @Xanewok

[mati865]

Cc @Zoxc

[msizanoen1]

@alexcrichton Can you run a try build?

[msizanoen1]

I have already tested this locally. RLS and Rustfmt builds and Miri is failing because of unrelated issues (#65684). Clippy for cross platforms is still waiting on rust-lang/rust-clippy#4714

[bors]

☔ The latest upstream changes (presumably #65771) made this pull request unmergeable. Please resolve the merge conflicts.

[rust-highfive]

The job x86_64-gnu-llvm-6.0 of your PR failed (pretty log, 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.

2019-10-25T06:21:40.4132676Z ##[command]git remote add origin https://github.com/rust-lang/rust
2019-10-25T06:21:40.4353147Z ##[command]git config gc.auto 0
2019-10-25T06:21:40.4438961Z ##[command]git config --get-all http.https://github.com/rust-lang/rust.extraheader
2019-10-25T06:21:40.4500613Z ##[command]git config --get-all http.proxy
2019-10-25T06:21:40.4630692Z ##[command]git -c http.extraheader="AUTHORIZATION: basic ***" fetch --force --tags --prune --progress --no-recurse-submodules --depth=2 origin +refs/heads/*:refs/remotes/origin/* +refs/pull/65698/merge:refs/remotes/pull/65698/merge
---
2019-10-25T06:39:01.8104364Z   local time: Fri Oct 25 06:39:01 UTC 2019
2019-10-25T06:39:02.0900837Z   network time: Fri, 25 Oct 2019 06:39:02 GMT
2019-10-25T06:39:02.0900958Z == end clock drift check ==
2019-10-25T06:39:05.2421460Z 
2019-10-25T06:39:05.2522640Z ##[error]Bash exited with code '1'.
2019-10-25T06:39:05.2616878Z ##[section]Starting: Checkout
2019-10-25T06:39:05.2618735Z ==============================================================================
2019-10-25T06:39:05.2618781Z Task         : Get sources
2019-10-25T06:39:05.2618822Z Description  : Get sources from a repository. Supports Git, TfsVC, and SVN repositories.

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)

[msizanoen1]

r? @Zoxc

[petrochenkov]

Wait, I've just got to reviewing this.

[petrochenkov]

r? @petrochenkov

[petrochenkov]

r=me with commits squashed

[msizanoen1]

How do I squash commits?

[tesuji]

Use git rebase -i master and follow instructions.
See https://github.com/wprig/wprig/wiki/How-to-squash-commits for more details.

[petrochenkov]

(I usually just soft-reset to the first commit and then amend everything else into it, it's pretty convenient to do from git gui.)

[Zoxc]

You could try cherry picking this PR just as a sanity check that things work: #56447

You can also do the CI cross compilation docker builds locally to ensure stuff works before trying to land this, if you haven't done so already.

[petrochenkov]

@msizanoen1
Could you notify me when you finish testing and making changes?

[msizanoen1]

@petrochenkov Testing done - all green tools on toolstate builds (except clippy - rust-lang/rust-clippy#4714) after introducing serde-derive dependency on rustc.

[petrochenkov]

@bors r+

[bors]

📌 Commit 03e7964cd9a2d6ff89ecb0fb9b3ea5b066b5ff39 has been approved by petrochenkov

[bors]

☔ The latest upstream changes (presumably #65990) made this pull request unmergeable. Please resolve the merge conflicts.

[msizanoen1]

@petrochenkov Rebased for conflict resolution.

[petrochenkov]

@bors r+

[bors]

📌 Commit 8a0d233 has been approved by petrochenkov

[bors]

⌛ Testing commit 8a0d233 with merge 253fc0e...

[bors]

☀️ Test successful - checks-azure
Approved by: petrochenkov
Pushing 253fc0e to master...