Add def path data variant

[spastorino]

This one should be merged after #104615

r? @compiler-errors

[spastorino]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[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 add-def-path-data-variant (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 add-def-path-data-variant --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

Auto-merging compiler/rustc_trait_selection/src/traits/project.rs
Auto-merging compiler/rustc_trait_selection/src/traits/object_safety.rs
CONFLICT (content): Merge conflict in compiler/rustc_trait_selection/src/traits/object_safety.rs
Auto-merging compiler/rustc_resolve/src/def_collector.rs
Auto-merging compiler/rustc_passes/src/check_attr.rs
Auto-merging compiler/rustc_middle/src/ty/print/pretty.rs
Auto-merging compiler/rustc_middle/src/ty/mod.rs
Auto-merging compiler/rustc_middle/src/ty/error.rs
Auto-merging compiler/rustc_hir_analysis/src/check/compare_method.rs
Auto-merging compiler/rustc_hir_analysis/src/check/check.rs
Auto-merging compiler/rustc_hir_analysis/src/astconv/mod.rs
Auto-merging compiler/rustc_ast_lowering/src/lib.rs
Automatic merge failed; fix conflicts and then commit the result.

[spastorino]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[bors]

⌛ Trying commit 4c65464ed1c5a2bfb507ac05929ba0aecb34102b with merge e8579d4778471621b7779a36e65222948cbbaa63...

[bors]

💔 Test failed - checks-actions

[cjgillot]

I'm not sure what the motivation is. Could you elaborate on what this helps with? Why isn't a DefKind variant not enough?

[cjgillot]

This may cause issues with incremental compilation. DefPathData is hashed using Hash and not StableHasher. This means that we may change the DefPathHash when DefIndices are re-numbered, which is what DefPathHash is supposed to avoid.

[cjgillot]

Can this be implemented by walking self.parent until we find a ValueNs? As for of_trait I haven't seen it used anywhere, could it be computed from fn_def_id?

[spastorino]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[bors]

⌛ Trying commit 41ef0554d171a62e0bf13d4f8156109f4f755de9 with merge ce79ba7e68d9b7fa6b693bc310d989b1099eb019...

[bors]

☔ The latest upstream changes (presumably #103491) made this pull request unmergeable. Please resolve the merge conflicts.

[spastorino]

We don't need to use this hack anymore as #104940 was r+ed.