Internal lints: usage_of_qualified_ty & ty_pass_by_reference

[flip1995]

Closes #59952

Implements internal lints:

• USAGE_OF_QUALIFIED_TY
• TY_PASS_BY_REFERENCE

r? @oli-obk

[rust-highfive]

The job x86_64-gnu-llvm-6.0 of 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.

travis_time:end:09da5e99:start=1556298194956616060,finish=1556298197186123155,duration=2229507095
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
$ export GCP_CACHE_BUCKET=rust-lang-ci-cache
$ export AWS_ACCESS_KEY_ID=AKIA46X5W6CZEJZ6XT55
---
[00:53:34]    Compiling rustdoc v0.0.0 (/checkout/src/librustdoc)
[00:53:44] error: passing `TyCtxt<'_, '_, '_>` by reference
[00:53:44]    --> src/librustdoc/clean/auto_trait.rs:853:29
[00:53:44]     |
[00:53:44] 853 |     fn is_fn_ty(&self, tcx: &TyCtxt<'_, '_, '_>, ty: &Type) -> bool {
[00:53:44]     |                             ^^^^^^^^^^^^^^^^^^^ help: try passing by value: `TyCtxt<'_, '_, '_>`
[00:53:44] note: lint level defined here
[00:53:44]    --> src/librustdoc/lib.rs:2:9
[00:53:44]     |
[00:53:44] 2   | #![deny(internal)]
[00:53:44] 2   | #![deny(internal)]
[00:53:44]     |         ^^^^^^^^
[00:53:44]     = note: #[deny(ty_pass_by_reference)] implied by #[deny(internal)]
[00:53:44] error: passing `TyCtxt<'_, '_, '_>` by reference
[00:53:44]     --> src/librustdoc/clean/mod.rs:4400:31
[00:53:44]      |
[00:53:44]      |
[00:53:44] 4400 | pub fn path_to_def_local(tcx: &TyCtxt<'_, '_, '_>, path: &[&str]) -> Option<DefId> {
[00:53:44]      |                               ^^^^^^^^^^^^^^^^^^^ help: try passing by value: `TyCtxt<'_, '_, '_>`
[00:53:44] error: passing `TyCtxt<'_, '_, '_>` by reference
[00:53:44]     --> src/librustdoc/clean/mod.rs:4425:25
[00:53:44]      |
[00:53:44]      |
[00:53:44] 4425 | pub fn path_to_def(tcx: &TyCtxt<'_, '_, '_>, path: &[&str]) -> Option<DefId> {
[00:53:44]      |                         ^^^^^^^^^^^^^^^^^^^ help: try passing by value: `TyCtxt<'_, '_, '_>`
[00:53:45] error: aborting due to 3 previous errors
[00:53:45] 
[00:53:45] error: Could not compile `rustdoc`.
[00:53:45] 
---
travis_time:end:0c88f092:start=1556301434970716526,finish=1556301434976965554,duration=6249028
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:0106019e
$ ln -s . checkout && for CORE in obj/cores/core.*; do EXE=$(echo $CORE | sed 's|obj/cores/core\.[0-9]*\.!checkout!\(.*\)|\1|;y|!|/|'); if [ -f "$EXE" ]; then printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" "$CORE"; gdb --batch -q -c "$CORE" "$EXE" -iex 'set auto-load off' -iex 'dir src/' -iex 'set sysroot .' -ex bt -ex q; echo travis_fold":"end:crashlog; fi; done || true
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:0120959c
travis_time:start:0120959c
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:09d21b63
$ dmesg | grep -i kill

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)

[bors]

☔ The latest upstream changes (presumably #60329) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

needs a rebase, r=me with that

@bors delegate+

[bors]

✌️ @flip1995 can now approve this pull request

[bors]

☔ The latest upstream changes (presumably #60351) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

@bors p=1 super bitrotty apparently

[flip1995]

Also removed the unused argument from the allow_two_phase_borrow function. cc #60347

@bors r=oli-obk

[bors]

📌 Commit 2e5f0b3 has been approved by oli-obk

[bors]

⌛ Testing commit 2e5f0b3 with merge 272000c...

[bors]

☀️ Test successful - checks-travis, status-appveyor
Approved by: oli-obk
Pushing 272000c to master...

[eddyb]

Wow, that's a neat trick! cc @nikomatsakis how did we not think of this?

[eddyb]

{visit,super}_{local,region,const} (and maybe a few others?) should probably get the same treatment.

[nikomatsakis]

heh, a good question.