Implement PartialOrd<&B> for &mut A

[Duddino]

Fixes #65589

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @cramertj (or someone else) soon.

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[ecstatic-morse]

@Duddino Could you remove the submodule update to MIRI?

[rust-highfive]

The job LinuxTools 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.

2019-10-19T20:45:17.6780037Z ##[command]git remote add origin https://github.com/rust-lang/rust
2019-10-19T20:45:17.7009589Z ##[command]git config gc.auto 0
2019-10-19T20:45:17.7103362Z ##[command]git config --get-all http.https://github.com/rust-lang/rust.extraheader
2019-10-19T20:45:17.7168705Z ##[command]git config --get-all http.proxy
2019-10-19T20:45:17.7318931Z ##[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/65609/merge:refs/remotes/pull/65609/merge
---
2019-10-19T22:40:20.1979358Z     Finished release [optimized] target(s) in 9m 14s
2019-10-19T22:42:00.7805321Z Error: there are broken links
2019-10-19T22:42:00.7806647Z  Caused By: "https://doc.rust-lang.org/nightly/nightly-rustc/syntax/parse/struct.ParseSess.html" returned 404 Not Found
2019-10-19T22:42:00.7808230Z  Caused By: "https://doc.rust-lang.org/nightly/nightly-rustc/syntax/parse/struct.ParseSess.html#method.buffer_lint" returned 404 Not Found
2019-10-19T22:42:00.7809918Z  Caused By: "***/tree/master/src/libsyntax/ext/tt" returned 404 Not Found
2019-10-19T22:42:00.7811151Z  Caused By: "https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ext/tt/macro_parser/fn.parse.html" returned 404 Not Found
2019-10-19T22:42:00.7811646Z  Caused By: "https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ext/tt/macro_rules/" returned 404 Not Found
2019-10-19T22:42:00.7811932Z  Caused By: "https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ext/tt/macro_parser/" returned 404 Not Found
2019-10-19T22:42:00.7812613Z  Caused By: "https://github.com/rust-lang/chalk/blob/master/src/test/wf.rs" returned 404 Not Found
---
2019-10-19T23:30:06.6896128Z Verifying status of clippy-driver...
2019-10-19T23:30:06.6911708Z Verifying status of miri...
2019-10-19T23:30:06.6926536Z This PR updated 'src/tools/miri', verifying if status is 'test-pass'...
2019-10-19T23:30:06.6941306Z 
2019-10-19T23:30:06.6942323Z ⚠️ We detected that this PR updated 'miri', but its tests failed.
2019-10-19T23:30:06.6942603Z 
2019-10-19T23:30:06.6942930Z If you do intend to update 'miri', please check the error messages above and
2019-10-19T23:30:06.6943061Z commit another update.
2019-10-19T23:30:06.6943088Z 
2019-10-19T23:30:06.6943344Z If you do NOT intend to update 'miri', please ensure you did not accidentally
2019-10-19T23:30:06.6943601Z change the submodule at 'src/tools/miri'. You may ask your reviewer for the
2019-10-19T23:30:06.6943667Z proper steps.
2019-10-19T23:30:06.6967145Z   local time: Sat Oct 19 23:30:06 UTC 2019
2019-10-19T23:30:06.8541843Z   network time: Sat, 19 Oct 2019 23:30:06 GMT
2019-10-19T23:30:06.8545442Z == end clock drift check ==
2019-10-19T23:30:08.3311894Z 
2019-10-19T23:30:08.3311894Z 
2019-10-19T23:30:08.3440452Z ##[error]Bash exited with code '3'.
2019-10-19T23:30:08.3491300Z ##[section]Starting: Checkout
2019-10-19T23:30:08.3497194Z ==============================================================================
2019-10-19T23:30:08.3497306Z Task         : Get sources
2019-10-19T23:30:08.3497353Z 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)

[Duddino]

@Duddino Could you remove the submodule update to MIRI?

Yeah... I accidentally undid athe last MIRI commit I think

[Duddino]

I think the easiest solution is to make another PR