Erase regions in writeback by matthewjasper · Pull Request #69189 · rust-lang/rust

matthewjasper · 2020-02-15T16:28:24Z

Regions in TypeckTables (except canonicalized user annotations) are now erased. Further, we no longer do lexical region solving on item bodies with -Zborrowck=mir.

cc #68261
r? @nikomatsakis

Avoid using regions from `TypeckTables` These regions will all be `ReErased` soon. (rust-lang/rust#69189) changelog: none

bors · 2020-02-17T02:06:34Z

☔ The latest upstream changes (presumably #67953) made this pull request unmergeable. Please resolve the merge conflicts.

joelpalmer · 2020-03-09T11:00:26Z

Triaged

nikomatsakis · 2020-03-12T14:30:09Z

src/librustc_infer/infer/mod.rs

Can we add a doc comment explaining the overall role of this type?

I was imagining that we might give some coverage of how regions are handled in type-check vs NLL here. Though really we ought to explain this in a rustc-dev-guide section and link to that

nikomatsakis · 2020-03-12T14:57:44Z

r=me with a comment, cc @matthewjasper

matthewjasper · 2020-03-12T19:45:18Z

@bors r=nikomatsakis

bors · 2020-03-12T19:45:20Z

📌 Commit f8a08a9 has been approved by nikomatsakis

@nikomatsakis

…komatsakis Erase regions in writeback Regions in `TypeckTables` (except canonicalized user annotations) are now erased. Further, we no longer do lexical region solving on item bodies with `-Zborrowck=mir`. cc rust-lang#68261 r? @nikomatsakis

@ghost

Rollup of 8 pull requests Successful merges: - #68746 (Make macro metavars respect (non-)hygiene) - #69189 (Erase regions in writeback) - #69402 (Extend search) - #69403 (Implement `Copy` for `IoSlice`) - #69460 (Move some `build-pass` tests to `check-pass`) - #69802 (fix more clippy findings) - #69809 (remove lifetimes that can be elided (clippy::needless_lifetimes)) - #69949 (triagebot.toml: add ping aliases) Failed merges: - #69589 (ast: `Mac`/`Macro` -> `MacCall`) r? @ghost

bors · 2020-03-14T20:04:14Z

☔ The latest upstream changes (presumably #69076) made this pull request unmergeable. Please resolve the merge conflicts.

@nikomatsakis

…komatsakis Erase regions in writeback Regions in `TypeckTables` (except canonicalized user annotations) are now erased. Further, we no longer do lexical region solving on item bodies with `-Zborrowck=mir`. cc rust-lang#68261 r? @nikomatsakis

@nikomatsakis

…komatsakis Erase regions in writeback Regions in `TypeckTables` (except canonicalized user annotations) are now erased. Further, we no longer do lexical region solving on item bodies with `-Zborrowck=mir`. cc rust-lang#68261 r? @nikomatsakis

@ghost

Rollup of 10 pull requests Successful merges: - rust-lang#67749 (keyword docs for else and inkeyword docs for else and in.) - rust-lang#69139 (clean up E0308 explanation) - rust-lang#69189 (Erase regions in writeback) - rust-lang#69837 (Use smaller discriminants for generators) - rust-lang#69838 (Expansion-driven outline module parsing) - rust-lang#69839 (Miri error reform) - rust-lang#69899 (Make methods declared by `newtype_index` macro `const`) - rust-lang#69920 (Remove some imports to the rustc crate) - rust-lang#70075 (Fix repr pretty display) - rust-lang#70106 (Tidy: fix running rustfmt twice) Failed merges: - rust-lang#70051 (Allow `hir().find` to return `None`) - rust-lang#70074 (Expand: nix all fatal errors) r? @ghost

eddyb · 2020-03-19T07:43:10Z

src/test/ui/transmute/main.stderr

   |
-   = note: source type: `<C as TypeConstructor<'a>>::T` (size can vary because of <C as TypeConstructor>::T)
-   = note: target type: `<C as TypeConstructor<'b>>::T` (size can vary because of <C as TypeConstructor>::T)
+   = note: `<C as TypeConstructor>::T` does not have a fixed size


Wait, we don't allow transmuting between the same type with only lifetimes changed?
I think we do when it's beyond a pointer, even if we don't know if it's Sized.

We don't allow transmutes between type projections at all it seems:

pub trait TypeConstructor { type T; } unsafe fn transmute_lifetime<C>(x: C::T) where C: TypeConstructor { transmute::<C::T, C::T>(x); // ERROR ! }

flip1995 · 2020-03-19T13:58:27Z

@matthewjasper Question regarding a Clippy rustup: rust-lang/rust-clippy#5333

Clippy has a check in the linting code that compares two types like this:

cx.tcx.expr_ty(expr1) == cx.tcx.expr_ty(expr2)

Before this PR, this returned false for &'a T == &'b T. Now it doesn't take the different lifetimes into account and returns true. Do you know of a way to compare two types taking their (user-defined) lifetimes into account?

rustup rust-lang/rust#69189 rustups rust-lang/rust#69189 which is part of rust-lang/rust#70085 (at least I think this is the only pr that changes clippy test stdout) changelog: none

eddyb · 2020-03-19T14:01:48Z

@flip1995 No, you were getting lucky before if that worked.
The only thing that can accurately reason about lifetimes is MIR borrowck.

@ghost

Rollup of 4 pull requests Successful merges: - #5326 (rustup rust-lang/rust#69838) - #5333 (rustup rust-lang/rust#69189) - #5336 (rustup rust-lang/rust#69920) - #5341 (Rustup to rust-lang/rust#66131) Failed merges: r? @ghost

@ghost

Rollup of 4 pull requests Successful merges: - #5326 (rustup rust-lang/rust#69838) - #5333 (rustup rust-lang/rust#69189) - #5336 (rustup rust-lang/rust#69920) - #5341 (Rustup to rust-lang/rust#66131) Failed merges: r? @ghost changelog: none

@ghost

Rollup of 4 pull requests Successful merges: - #5326 (rustup rust-lang/rust#69838) - #5333 (rustup rust-lang/rust#69189) - #5336 (rustup rust-lang/rust#69920) - #5341 (Rustup to rust-lang/rust#66131) Failed merges: r? @ghost changelog: none

@ghost

Rollup of 4 pull requests Successful merges: - #5326 (rustup rust-lang/rust#69838) - #5333 (rustup rust-lang/rust#69189) - #5336 (rustup rust-lang/rust#69920) - #5341 (Rustup to rust-lang/rust#66131) Failed merges: r? @ghost changelog: none

@ghost

Rollup of 4 pull requests Successful merges: - #5326 (rustup rust-lang/rust#69838) - #5333 (rustup rust-lang/rust#69189) - #5336 (rustup rust-lang/rust#69920) - #5341 (Rustup to rust-lang/rust#66131) Failed merges: r? @ghost changelog: none

rust-highfive assigned nikomatsakis Feb 15, 2020

rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Feb 15, 2020

matthewjasper mentioned this pull request Feb 15, 2020

Avoid using regions from TypeckTables rust-lang/rust-clippy#5177

Merged

bors added a commit to rust-lang/rust-clippy that referenced this pull request Feb 15, 2020

Auto merge of #5177 - matthewjasper:own-infer, r=flip1995

578960d

Avoid using regions from `TypeckTables` These regions will all be `ReErased` soon. (rust-lang/rust#69189) changelog: none

This comment has been minimized.

Sign in to view

matthewjasper force-pushed the erase-the-world branch from 86161e0 to 5ce0263 Compare February 15, 2020 18:13

JohnCSimon added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Mar 2, 2020

matthewjasper force-pushed the erase-the-world branch from 5ce0263 to 24f824c Compare March 9, 2020 22:08

matthewjasper added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Mar 12, 2020

nikomatsakis approved these changes Mar 12, 2020

View reviewed changes

nikomatsakis added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Mar 12, 2020

matthewjasper force-pushed the erase-the-world branch from 24f824c to f8a08a9 Compare March 12, 2020 18:37

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Mar 12, 2020

Centril mentioned this pull request Mar 12, 2020

Rollup of 8 pull requests #69958

Closed

nikomatsakis mentioned this pull request Mar 13, 2020

Make the type_of return a generic type for generators #68884

Merged

bors added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Mar 14, 2020

matthewjasper force-pushed the erase-the-world branch from f8a08a9 to e53bc00 Compare March 15, 2020 12:42

Centril mentioned this pull request Mar 18, 2020

Rollup of 8 pull requests #70099

Closed

Centril mentioned this pull request Mar 18, 2020

Rollup of 10 pull requests #70109

Closed

Centril mentioned this pull request Mar 18, 2020

Rollup of 10 pull requests #70110

Closed

Centril mentioned this pull request Mar 18, 2020

Rollup of 10 pull requests #70112

Merged

bors merged commit 3f583fc into rust-lang:master Mar 19, 2020

eddyb reviewed Mar 19, 2020

View reviewed changes

matthewjasper deleted the erase-the-world branch March 19, 2020 09:00

flip1995 mentioned this pull request Mar 19, 2020

Rollup of 4 pull requests rust-lang/rust-clippy#5342

Merged

flip1995 mentioned this pull request Mar 19, 2020

Regression in useless_transmute due to rustup rust-lang/rust-clippy#5343

Open

SimonSapin mentioned this pull request Mar 20, 2020

Importing modules from inside include! no longer works #70185

Closed

Centril mentioned this pull request Mar 31, 2020

internal compiler error: cannot relate region: LUB(ReErased, ReErased) #70608

Closed

matthewjasper mentioned this pull request May 20, 2020

Don't infer regions in type checking #68261

Closed

jplatte mentioned this pull request May 27, 2020

ICE with const_generics + const_compare_raw_pointers: broken MIR / NoSolution #72352

Closed

Uh oh!

Conversation

matthewjasper commented Feb 15, 2020

Uh oh!

This comment has been minimized.

bors commented Feb 17, 2020

Uh oh!

joelpalmer commented Mar 9, 2020

Uh oh!

nikomatsakis Mar 12, 2020

Choose a reason for hiding this comment

Uh oh!

nikomatsakis Mar 12, 2020

Choose a reason for hiding this comment

Uh oh!

nikomatsakis commented Mar 12, 2020

Uh oh!

matthewjasper commented Mar 12, 2020

Uh oh!

bors commented Mar 12, 2020

Uh oh!

bors commented Mar 14, 2020

Uh oh!

eddyb Mar 19, 2020

Choose a reason for hiding this comment

Uh oh!

matthewjasper Mar 19, 2020

Choose a reason for hiding this comment

Uh oh!

flip1995 commented Mar 19, 2020

Uh oh!

eddyb commented Mar 19, 2020

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

9 participants