Conditionally skip two passes if their related attributes were not found

[Zoxc]

No description provided.

[rust-highfive]

r? @matthewjasper

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

[matthewjasper]

r? @petrochenkov

[bors]

☔ The latest upstream changes (presumably #57869) made this pull request unmergeable. Please resolve the merge conflicts.

[petrochenkov]

AST validation is supposed to work on the "final" AST and check that internal expansion passes don't produce anything suspicious either.
That's why it was placed after all the proc-macro/allocator expansions.
That's certainly less important than checking user input though.

Beside that collecting flags for later passes seems "off-topic" for AST validation.

Still seems ok, other passes are even less suitable for collecting the flags for this optimization.
@bors r+

[bors]

📌 Commit c8f51324b5789e7dd3e8f9a923dc4a350a24f1a4 has been approved by petrochenkov

[bors]

🔒 Merge conflict

This pull request and the master branch diverged in a way that cannot be automatically merged. Please rebase on top of the latest master branch, and let the reviewer approve again.

How do I rebase?

Assuming self is your fork and upstream is this repository, you can resolve the conflict following these steps:

1. git checkout pass-skip (switch to your branch)
2. git fetch upstream master (retrieve the latest master)
3. git rebase upstream/master -p (rebase on top of it)
4. Follow the on-screen instruction to resolve conflicts (check git status if you got lost).
5. git push self pass-skip --force-with-lease (update this PR)

You may also read Git Rebasing to Resolve Conflicts by Drew Blessing for a short tutorial.

Please avoid the "Resolve conflicts" button on GitHub. It uses git merge instead of git rebase which makes the PR commit history more difficult to read.

Sometimes step 4 will complete without asking for resolution. This is usually due to difference between how Cargo.lock conflict is handled during merge and rebase. This is normal, and you should still perform step 5 to update this PR.

Error message

warning: Cannot merge binary files: Cargo.lock (HEAD vs. heads/homu-tmp)
Auto-merging src/librustc_passes/lib.rs
Auto-merging src/librustc_passes/ast_validation.rs
CONFLICT (content): Merge conflict in src/librustc_passes/ast_validation.rs
Auto-merging src/librustc_driver/driver.rs
Auto-merging Cargo.lock
CONFLICT (content): Merge conflict in Cargo.lock
Automatic merge failed; fix conflicts and then commit the result.

[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:0413038e:start=1548601462533702093,finish=1548601463580519019,duration=1046816926
$ 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
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
######################################################################    98.6%
######################################################################## 100.0%
[00:02:20] extracting /checkout/obj/build/cache/2019-01-04/cargo-beta-x86_64-unknown-linux-gnu.tar.gz
[00:02:20]     Updating crates.io index
[00:02:31] error: the lock file /checkout/Cargo.lock needs to be updated but --locked was passed to prevent this
[00:02:31] Build completed unsuccessfully in 0:00:26
[00:02:31] Makefile:70: recipe for target 'prepare' failed
[00:02:31] make: *** [prepare] Error 1
[00:02:32] Command failed. Attempt 2/5:
[00:02:32] Command failed. Attempt 2/5:
[00:02:32] error: the lock file /checkout/Cargo.lock needs to be updated but --locked was passed to prevent this
[00:02:32] Build completed unsuccessfully in 0:00:00
[00:02:32] Makefile:70: recipe for target 'prepare' failed
[00:02:32] make: *** [prepare] Error 1
[00:02:34] Command failed. Attempt 3/5:
[00:02:34] Command failed. Attempt 3/5:
[00:02:35] error: the lock file /checkout/Cargo.lock needs to be updated but --locked was passed to prevent this
[00:02:35] Build completed unsuccessfully in 0:00:00
[00:02:35] make: *** [prepare] Error 1
[00:02:35] Makefile:70: recipe for target 'prepare' failed
[00:02:38] Command failed. Attempt 4/5:
[00:02:38] Command failed. Attempt 4/5:
[00:02:38] error: the lock file /checkout/Cargo.lock needs to be updated but --locked was passed to prevent this
[00:02:38] Build completed unsuccessfully in 0:00:00
[00:02:38] Makefile:70: recipe for target 'prepare' failed
[00:02:38] make: *** [prepare] Error 1
[00:02:42] Command failed. Attempt 5/5:
[00:02:42] Command failed. Attempt 5/5:
[00:02:43] error: the lock file /checkout/Cargo.lock needs to be updated but --locked was passed to prevent this
[00:02:43] Build completed unsuccessfully in 0:00:00
[00:02:43] make: *** [prepare] Error 1
[00:02:43] Makefile:70: recipe for target 'prepare' failed
[00:02:43] The command has failed after 5 attempts.
---
travis_time:end:0407f010:start=1548601641032659799,finish=1548601641038532664,duration=5872865
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:26c47241
$ 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:009ac55a
travis_time:start:009ac55a
$ 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:1a00ce97
$ 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)

[Zoxc]

@bors r=petrochenkov

[bors]

📌 Commit cfe6544 has been approved by petrochenkov

[bors]

🔒 Merge conflict

This pull request and the master branch diverged in a way that cannot be automatically merged. Please rebase on top of the latest master branch, and let the reviewer approve again.

How do I rebase?

Assuming self is your fork and upstream is this repository, you can resolve the conflict following these steps:

1. git checkout pass-skip (switch to your branch)
2. git fetch upstream master (retrieve the latest master)
3. git rebase upstream/master -p (rebase on top of it)
4. Follow the on-screen instruction to resolve conflicts (check git status if you got lost).
5. git push self pass-skip --force-with-lease (update this PR)

You may also read Git Rebasing to Resolve Conflicts by Drew Blessing for a short tutorial.

Please avoid the "Resolve conflicts" button on GitHub. It uses git merge instead of git rebase which makes the PR commit history more difficult to read.

Sometimes step 4 will complete without asking for resolution. This is usually due to difference between how Cargo.lock conflict is handled during merge and rebase. This is normal, and you should still perform step 5 to update this PR.

Error message

warning: Cannot merge binary files: Cargo.lock (HEAD vs. heads/homu-tmp)
Auto-merging Cargo.lock
CONFLICT (content): Merge conflict in Cargo.lock
Automatic merge failed; fix conflicts and then commit the result.

[Zoxc]

@bors r=petrochenkov

[bors]

📌 Commit 1bdd2f6 has been approved by petrochenkov

[bors]

⌛ Testing commit 1bdd2f6 with merge cc4d1e5...

[bors]

☀️ Test successful - checks-travis, status-appveyor
Approved by: petrochenkov
Pushing cc4d1e5 to master...

[bors]

☀️ Test successful - checks-travis, status-appveyor
Approved by: petrochenkov
Pushing cc4d1e5 to master...