stop replacing bivariant args with 'static when computing closure requirements
#133798
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It is unnecessary, these get constrained when checking that the opaque type is well-formed. It also results in the opaque type no longer being well formed. If you've got `fn foo<'a>() -> impl Sized + 'a` the opaque is `type Opaque<'a, 'aDummy> where 'a: 'aDummy, 'aDummy: 'a` where `'aDummy` is bivariant. If we call `foo::<'b>()` inside of a closure and its return type ends up in a type test, we start out with the WF `Opaque<'b, 'b>`, and then replace the bivariant `'b` with `'static`. `Opaque<'b, 'static>` is no longer well-formed. Given how these type tests are used, I don't think this caused any practical issues.
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…iaskrgr Rollup of 6 pull requests Successful merges: - rust-lang#133651 (Update `NonZero` and `NonNull` to not field-project (per MCP#807)) - rust-lang#133764 (rustdoc: Rename `set_back_info` to `restore_module_data`.) - rust-lang#133784 (Fix MutVisitor's default implementations to visit Stmt's and BinOp's spans) - rust-lang#133798 (stop replacing bivariant args with `'static` when computing closure requirements) - rust-lang#133804 (Improve code for FileName retrieval in rustdoc) - rust-lang#133817 (Use `eprintln` instead of `println` in bootstrap/compiletest/tidy) Failed merges: - rust-lang#133810 (remove unnecessary `eval_verify_bound`) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#133798 - lcnr:nested-bodies-opaques, r=compiler-errors stop replacing bivariant args with `'static` when computing closure requirements It is unnecessary, these get constrained when checking that the opaque type is well-formed. It also results in the opaque type no longer being well formed. If you've got `fn foo<'a>() -> impl Sized + 'a` the opaque is `type Opaque<'a, 'aDummy> where 'a: 'aDummy, 'aDummy: 'a` where `'aDummy` is bivariant. If we call `foo::<'b>()` inside of a closure and its return type ends up in a type test, we start out with the WF `Opaque<'b, 'b>`, and then replace the bivariant `'b` with `'static`. `Opaque<'b, 'static>` is no longer well-formed. Given how these type tests are used, I don't think this caused any practical issues. r? types
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It is unnecessary, these get constrained when checking that the opaque type is well-formed.
It also results in the opaque type no longer being well formed. If you've got
fn foo<'a>() -> impl Sized + 'athe opaque istype Opaque<'a, 'aDummy> where 'a: 'aDummy, 'aDummy: 'awhere'aDummyis bivariant. If we callfoo::<'b>()inside of a closure and its return type ends up in a type test, we start out with the WFOpaque<'b, 'b>, and then replace the bivariant'bwith'static.Opaque<'b, 'static>is no longer well-formed. Given how these type tests are used, I don't think this caused any practical issues.r? types