Remove `RegionExt`; move methods to `Region` in `rustc_type_ir` by Jamesbarford · Pull Request #160509 · rust-lang/rust

Jamesbarford · 2026-08-04T13:49:59Z

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Removes RegionExt from rustc_middle with all methods on Region.

Some changes I think are worth pointing out (of which are all in the first commit -> f949bb7) ;

Changed the signature of Region::new_late_param to accept a I::LateParamRegion where previously it was able to construct a LateParamRegion from some method parameters.

added to interner:

fn span_delayed_bug(self, span: Self::Span, msg: impl ToString) -> Self::ErrorGuaranteed; which could be useful elsewhere when porting things across to rustc_type_ir
fn generics_of_early_param_region_def_id(self, def_id: Self::DefId, ebr: Self::EarlyParamRegion) -> Self::DefId; which is quite nasty but calling generics_of returned another type that I would have possibly create a trait for which felt more messy.
fn get_re_var_lifetime(self, var_idx: usize) -> Option<Region<'tcx>> need to get a region in Region::new_var.

traits added to inherent

RegionName so we can get the names of LateParamRegion and EarlyParamRegion with a get_name() and also is_named().
DefIdGetter so we can get the DefId of kind in LateParamRegion

r? lcnr

Part of #159654

rustbot · 2026-08-04T13:50:04Z

HIR ty lowering was modified

cc @fmease

lcnr · 2026-08-04T13:57:34Z

generics_of_early_param_region_def_id

hmm, without looking much at the code, I feel like we should move Generics into rustc_type_ir instead 🤔 how much effort is that/actually make it an inherent trait to make that transition easier in the future

lcnr · 2026-08-11T09:28:49Z

-                let r = ty::Region::new_late_param(self.infcx.tcx, self.mir_def.to_def_id(), kind);
+                let r = ty::Region::new_late_param(
+                    self.infcx.tcx,
+                    ty::LateParamRegion { scope: self.mir_def.to_def_id(), kind },


alternative, rustc and rustc_type_ir agree on LateParamRegion except that they represent the actual region differently, which tbh, they shouldn't do 🤣 could we just move LateParamRegion into rustc_type_ir and then keep the current fn sig here?

View changes since the review

I'm a bit slow on the uptake here, what do you mean by "just move"? Make a;

struct LateParamRegion<I: Interner> { pub scope: I::DefId, pub kind: I::LateParamRegionKind, }

And possibly port across; pub enum LateParamRegionKind { too ?

exactly. LateParamRegionKind should prolly also be moved even if r-a currently slightly differs, I think it's easier for them to just use the same type

#160986 <- done

with late param region being uplifted, you can keep this as two separate function arguments

@lcnr

…-region, r=lcnr Move `LateParamRegion` to `rustc_type_ir` Move `LateParamRegion` to `rustc_type_ir`. As per feedback, I created a `TrivialLiftImpls!` mirroring `rustc_middle`'s variant which is creates an identity function for `lift_to_interner(...)`. Spun off from; rust-lang#160509 r? @lcnr

@lcnr

…-region, r=lcnr Move `LateParamRegion` to `rustc_type_ir` Move `LateParamRegion` to `rustc_type_ir`. As per feedback, I created a `TrivialLiftImpls!` mirroring `rustc_middle`'s variant which is creates an identity function for `lift_to_interner(...)`. Spun off from; rust-lang#160509 r? @lcnr

@lcnr

Rollup merge of #160986 - Jamesbarford:chore/move-late-param-region, r=lcnr Move `LateParamRegion` to `rustc_type_ir` Move `LateParamRegion` to `rustc_type_ir`. As per feedback, I created a `TrivialLiftImpls!` mirroring `rustc_middle`'s variant which is creates an identity function for `lift_to_interner(...)`. Spun off from; #160509 r? @lcnr

@lcnr

…r=lcnr Move `LateParamRegion` to `rustc_type_ir` Move `LateParamRegion` to `rustc_type_ir`. As per feedback, I created a `TrivialLiftImpls!` mirroring `rustc_middle`'s variant which is creates an identity function for `lift_to_interner(...)`. Spun off from; rust-lang/rust#160509 r? @lcnr

rustbot · 2026-09-04T10:08:37Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

fmease · 2026-09-04T10:24:04Z

@bors r=lcnr

rust-bors · 2026-09-04T10:24:07Z

📌 Commit f3cf30d has been approved by lcnr

It is now in the queue for this repository.

…xt-triats-pt2, r=lcnr Remove `RegionExt`; move methods to `Region` in `rustc_type_ir` Removes `RegionExt` from `rustc_middle` with all methods on `Region`. Some changes I think are worth pointing out (of which are all in the first commit -> f949bb7) ; - Changed the signature of `Region::new_late_param` to accept a `I::LateParamRegion` where previously it was able to construct a `LateParamRegion` from some method parameters. **added to interner:** - `fn span_delayed_bug(self, span: Self::Span, msg: impl ToString) -> Self::ErrorGuaranteed;` which could be useful elsewhere when porting things across to `rustc_type_ir` - `fn generics_of_early_param_region_def_id(self, def_id: Self::DefId, ebr: Self::EarlyParamRegion) -> Self::DefId;` which is quite nasty but calling `generics_of` returned another type that I would have possibly create a trait for which felt more messy. - `fn get_re_var_lifetime(self, var_idx: usize) -> Option<Region<'tcx>>` need to get a region in `Region::new_var`. **traits added to inherent** - `RegionName` so we can get the names of `LateParamRegion` and `EarlyParamRegion` with a `get_name()` and also `is_named()`. - `DefIdGetter` so we can get the `DefId` of `kind` in `LateParamRegion` r? lcnr Part of rust-lang#159654

Rollup of 25 pull requests Successful merges: - #159074 ([PAC] FnAbi, llvm.ptrauth.resign and Session API change (2/8)) - #159792 (A more readable debug map for IndexMaps) - #161895 (std::sys::pal::sgx: fix mismatched alloc/free alignment) - #161900 (bootstrap: Include feature-gated items in bootstrap tool docs) - #161940 (Promote `wasm32-wasip3` to a tier 2 target) - #162072 (Add new Tier-3 target: `powerpc64-sony-ps3`) - #162179 (type system const items via direct rhs) - #162277 (Introduce `rustc_middle::middel::resolve`) - #162285 (box: fixup map/try_map deallocate calls) - #162286 (string: don't unwind prematurely) - #162289 (alloc: a bunch of safety comments) - #162292 (Update `askama` version to `0.16.1`) - #160509 (Remove `RegionExt`; move methods to `Region` in `rustc_type_ir`) - #160906 (Suggest usize instead of placeholder type for array length constants) - #160936 (traits: Represent live alias arguments as bitsets) - #161400 (Improve diagnostics for references to closures) - #161656 (Suggest mutable references for FnMut closure arguments) - #161711 (Add more splat fn type tests) - #161786 (Make `tcx.def_id_partial_cmp` public) - #161953 (sanitizers: Implicitly disable mutually exclusive sanitizers) - #162155 (add suggestion for `rustc_allowed_through_unstable_modules` attribute) - #162212 (Implement `Rng` for `Box`) - #162246 (Fix incorrect meta span) - #162266 (std: fix typo) - #162291 (Add regression test from 1.98.1)

…xt-triats-pt2, r=lcnr Remove `RegionExt`; move methods to `Region` in `rustc_type_ir` Removes `RegionExt` from `rustc_middle` with all methods on `Region`. Some changes I think are worth pointing out (of which are all in the first commit -> f949bb7) ; - Changed the signature of `Region::new_late_param` to accept a `I::LateParamRegion` where previously it was able to construct a `LateParamRegion` from some method parameters. **added to interner:** - `fn span_delayed_bug(self, span: Self::Span, msg: impl ToString) -> Self::ErrorGuaranteed;` which could be useful elsewhere when porting things across to `rustc_type_ir` - `fn generics_of_early_param_region_def_id(self, def_id: Self::DefId, ebr: Self::EarlyParamRegion) -> Self::DefId;` which is quite nasty but calling `generics_of` returned another type that I would have possibly create a trait for which felt more messy. - `fn get_re_var_lifetime(self, var_idx: usize) -> Option<Region<'tcx>>` need to get a region in `Region::new_var`. **traits added to inherent** - `RegionName` so we can get the names of `LateParamRegion` and `EarlyParamRegion` with a `get_name()` and also `is_named()`. - `DefIdGetter` so we can get the `DefId` of `kind` in `LateParamRegion` r? lcnr Part of rust-lang#159654

Rollup of 25 pull requests Successful merges: - #159074 ([PAC] FnAbi, llvm.ptrauth.resign and Session API change (2/8)) - #159792 (A more readable debug map for IndexMaps) - #160745 (make closures act like MaybeDangling) - #161895 (std::sys::pal::sgx: fix mismatched alloc/free alignment) - #161940 (Promote `wasm32-wasip3` to a tier 2 target) - #162072 (Add new Tier-3 target: `powerpc64-sony-ps3`) - #162179 (type system const items via direct rhs) - #162277 (Introduce `rustc_middle::middel::resolve`) - #162285 (box: fixup map/try_map deallocate calls) - #162286 (string: don't unwind prematurely) - #162289 (alloc: a bunch of safety comments) - #162292 (Update `askama` version to `0.16.1`) - #160509 (Remove `RegionExt`; move methods to `Region` in `rustc_type_ir`) - #160906 (Suggest usize instead of placeholder type for array length constants) - #160936 (traits: Represent live alias arguments as bitsets) - #161400 (Improve diagnostics for references to closures) - #161656 (Suggest mutable references for FnMut closure arguments) - #161711 (Add more splat fn type tests) - #161786 (Make `tcx.def_id_partial_cmp` public) - #161953 (sanitizers: Implicitly disable mutually exclusive sanitizers) - #162155 (add suggestion for `rustc_allowed_through_unstable_modules` attribute) - #162212 (Implement `Rng` for `Box`) - #162246 (Fix incorrect meta span) - #162266 (std: fix typo) - #162291 (Add regression test from 1.98.1)

…xt-triats-pt2, r=lcnr Remove `RegionExt`; move methods to `Region` in `rustc_type_ir` Removes `RegionExt` from `rustc_middle` with all methods on `Region`. Some changes I think are worth pointing out (of which are all in the first commit -> f949bb7) ; - Changed the signature of `Region::new_late_param` to accept a `I::LateParamRegion` where previously it was able to construct a `LateParamRegion` from some method parameters. **added to interner:** - `fn span_delayed_bug(self, span: Self::Span, msg: impl ToString) -> Self::ErrorGuaranteed;` which could be useful elsewhere when porting things across to `rustc_type_ir` - `fn generics_of_early_param_region_def_id(self, def_id: Self::DefId, ebr: Self::EarlyParamRegion) -> Self::DefId;` which is quite nasty but calling `generics_of` returned another type that I would have possibly create a trait for which felt more messy. - `fn get_re_var_lifetime(self, var_idx: usize) -> Option<Region<'tcx>>` need to get a region in `Region::new_var`. **traits added to inherent** - `RegionName` so we can get the names of `LateParamRegion` and `EarlyParamRegion` with a `get_name()` and also `is_named()`. - `DefIdGetter` so we can get the `DefId` of `kind` in `LateParamRegion` r? lcnr Part of rust-lang#159654

Rollup of 27 pull requests Successful merges: - #159074 ([PAC] FnAbi, llvm.ptrauth.resign and Session API change (2/8)) - #159792 (A more readable debug map for IndexMaps) - #160745 (make closures act like MaybeDangling) - #161940 (Promote `wasm32-wasip3` to a tier 2 target) - #162030 (Prevent `--test` to be used in `rustdoc-html` testsuite) - #162072 (Add new Tier-3 target: `powerpc64-sony-ps3`) - #162179 (type system const items via direct rhs) - #162262 (Avoid manually instantiating some binders in error reporting with `-Znext-solver`) - #162277 (Introduce `rustc_middle::middel::resolve`) - #162285 (box: fixup map/try_map deallocate calls) - #162286 (string: don't unwind prematurely) - #162289 (alloc: a bunch of safety comments) - #162290 (abby test DSL: AliasTyOutlivesViaEnv) - #162292 (Update `askama` version to `0.16.1`) - #160509 (Remove `RegionExt`; move methods to `Region` in `rustc_type_ir`) - #160906 (Suggest usize instead of placeholder type for array length constants) - #160936 (traits: Represent live alias arguments as bitsets) - #161400 (Improve diagnostics for references to closures) - #161656 (Suggest mutable references for FnMut closure arguments) - #161711 (Add more splat fn type tests) - #161786 (Make `tcx.def_id_partial_cmp` public) - #161953 (sanitizers: Implicitly disable mutually exclusive sanitizers) - #162155 (add suggestion for `rustc_allowed_through_unstable_modules` attribute) - #162212 (Implement `Rng` for `Box`) - #162246 (Fix incorrect meta span) - #162266 (std: fix typo) - #162291 (Add regression test from 1.98.1)

…xt-triats-pt2, r=lcnr Remove `RegionExt`; move methods to `Region` in `rustc_type_ir` Removes `RegionExt` from `rustc_middle` with all methods on `Region`. Some changes I think are worth pointing out (of which are all in the first commit -> f949bb7) ; - Changed the signature of `Region::new_late_param` to accept a `I::LateParamRegion` where previously it was able to construct a `LateParamRegion` from some method parameters. **added to interner:** - `fn span_delayed_bug(self, span: Self::Span, msg: impl ToString) -> Self::ErrorGuaranteed;` which could be useful elsewhere when porting things across to `rustc_type_ir` - `fn generics_of_early_param_region_def_id(self, def_id: Self::DefId, ebr: Self::EarlyParamRegion) -> Self::DefId;` which is quite nasty but calling `generics_of` returned another type that I would have possibly create a trait for which felt more messy. - `fn get_re_var_lifetime(self, var_idx: usize) -> Option<Region<'tcx>>` need to get a region in `Region::new_var`. **traits added to inherent** - `RegionName` so we can get the names of `LateParamRegion` and `EarlyParamRegion` with a `get_name()` and also `is_named()`. - `DefIdGetter` so we can get the `DefId` of `kind` in `LateParamRegion` r? lcnr Part of rust-lang#159654

…uwer Rollup of 25 pull requests Successful merges: - #162072 (Add new Tier-3 target: `powerpc64-sony-ps3`) - #162179 (type system const items via direct rhs) - #162255 (let people change rustc-dev-guide in-tree) - #162262 (Avoid manually instantiating some binders in error reporting with `-Znext-solver`) - #162277 (Introduce `rustc_middle::middel::resolve`) - #162285 (box: fixup map/try_map deallocate calls) - #162286 (string: don't unwind prematurely) - #162289 (alloc: a bunch of safety comments) - #162290 (abby test DSL: AliasTyOutlivesViaEnv) - #162292 (Update `askama` version to `0.16.1`) - #160509 (Remove `RegionExt`; move methods to `Region` in `rustc_type_ir`) - #160906 (Suggest usize instead of placeholder type for array length constants) - #160936 (traits: Represent live alias arguments as bitsets) - #161394 (fix `is_homogeneous_aggregate`: use unit size, not total size ) - #161400 (Improve diagnostics for references to closures) - #161656 (Suggest mutable references for FnMut closure arguments) - #161711 (Add more splat fn type tests) - #161786 (Make `tcx.def_id_partial_cmp` public) - #161953 (sanitizers: Implicitly disable mutually exclusive sanitizers) - #162155 (add suggestion for `rustc_allowed_through_unstable_modules` attribute) - #162212 (Implement `Rng` for `Box`) - #162246 (Fix incorrect meta span) - #162266 (std: fix typo) - #162291 (Add regression test from 1.98.1) - #162303 (Fix a minor spelling error in `library/std/src/sys/fs/unix.rs`)

…xt-triats-pt2, r=lcnr Remove `RegionExt`; move methods to `Region` in `rustc_type_ir` Removes `RegionExt` from `rustc_middle` with all methods on `Region`. Some changes I think are worth pointing out (of which are all in the first commit -> f949bb7) ; - Changed the signature of `Region::new_late_param` to accept a `I::LateParamRegion` where previously it was able to construct a `LateParamRegion` from some method parameters. **added to interner:** - `fn span_delayed_bug(self, span: Self::Span, msg: impl ToString) -> Self::ErrorGuaranteed;` which could be useful elsewhere when porting things across to `rustc_type_ir` - `fn generics_of_early_param_region_def_id(self, def_id: Self::DefId, ebr: Self::EarlyParamRegion) -> Self::DefId;` which is quite nasty but calling `generics_of` returned another type that I would have possibly create a trait for which felt more messy. - `fn get_re_var_lifetime(self, var_idx: usize) -> Option<Region<'tcx>>` need to get a region in `Region::new_var`. **traits added to inherent** - `RegionName` so we can get the names of `LateParamRegion` and `EarlyParamRegion` with a `get_name()` and also `is_named()`. - `DefIdGetter` so we can get the `DefId` of `kind` in `LateParamRegion` r? lcnr Part of rust-lang#159654

…uwer Rollup of 25 pull requests Successful merges: - #162072 (Add new Tier-3 target: `powerpc64-sony-ps3`) - #162179 (type system const items via direct rhs) - #162255 (let people change rustc-dev-guide in-tree) - #162262 (Avoid manually instantiating some binders in error reporting with `-Znext-solver`) - #162277 (Introduce `rustc_middle::middel::resolve`) - #162285 (box: fixup map/try_map deallocate calls) - #162286 (string: don't unwind prematurely) - #162289 (alloc: a bunch of safety comments) - #162290 (abby test DSL: AliasTyOutlivesViaEnv) - #162292 (Update `askama` version to `0.16.1`) - #160509 (Remove `RegionExt`; move methods to `Region` in `rustc_type_ir`) - #160906 (Suggest usize instead of placeholder type for array length constants) - #160936 (traits: Represent live alias arguments as bitsets) - #161394 (fix `is_homogeneous_aggregate`: use unit size, not total size ) - #161400 (Improve diagnostics for references to closures) - #161656 (Suggest mutable references for FnMut closure arguments) - #161711 (Add more splat fn type tests) - #161786 (Make `tcx.def_id_partial_cmp` public) - #161953 (sanitizers: Implicitly disable mutually exclusive sanitizers) - #162155 (add suggestion for `rustc_allowed_through_unstable_modules` attribute) - #162212 (Implement `Rng` for `Box`) - #162246 (Fix incorrect meta span) - #162266 (std: fix typo) - #162291 (Add regression test from 1.98.1) - #162303 (Fix a minor spelling error in `library/std/src/sys/fs/unix.rs`)

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. T-rustdoc Relevant to the rustdoc team, which will review and decide on the PR/issue. labels Aug 4, 2026

rustbot assigned lcnr Aug 4, 2026

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