identity uses are ok, even if there are no defining uses #146206
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Rollup of 5 pull requests Successful merges: - #139524 (Add socket extensions for cygwin) - #145940 (single buffer for exponent fmt of integers) - #146206 (identity uses are ok, even if there are no defining uses) - #146272 (Update comment for `-Werror` on LLVM builds) - #146280 (Make `LetChainsPolicy` public for rustfmt usage) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #146206 - lcnr:fix-non-defining-uses, r=BoxyUwU identity uses are ok, even if there are no defining uses fix #146191 I've tried moving the "is this an identity use" check to `fn clone_and_resolve_opaque_types` and this would allow the following code to compile as it now ignores `Opaque<'!a> = Opaque<'!a>` while they previously resulted in errors https://github.com/rust-lang/rust/blob/71289c378d0a406a4f537fe4001282d19362931f/tests/ui/type-alias-impl-trait/hkl_forbidden.rs#L42-L46 The closure signature gets inferred to `for<'a> fn(&'a ()) -> Inner<'a>`. The closure then has a defining use `Inner<'a_latbound> = &'a_latebound ()` while the parent function has a non-defining `Inner<'!a> = Inner<'!a>`. By eagerly discarding identity uses we don't error on the non-defining use in the parent. r? `@BoxyUwU`
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Rollup of 5 pull requests Successful merges: - rust-lang/rust#139524 (Add socket extensions for cygwin) - rust-lang/rust#145940 (single buffer for exponent fmt of integers) - rust-lang/rust#146206 (identity uses are ok, even if there are no defining uses) - rust-lang/rust#146272 (Update comment for `-Werror` on LLVM builds) - rust-lang/rust#146280 (Make `LetChainsPolicy` public for rustfmt usage) r? `@ghost` `@rustbot` modify labels: rollup
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fix #146191
I've tried moving the "is this an identity use" check to
fn clone_and_resolve_opaque_typesand this would allow the following code to compile as it now ignoresOpaque<'!a> = Opaque<'!a>while they previously resulted in errorsrust/tests/ui/type-alias-impl-trait/hkl_forbidden.rs
Lines 42 to 46 in 71289c3
The closure signature gets inferred to
for<'a> fn(&'a ()) -> Inner<'a>. The closure then has a defining useInner<'a_latbound> = &'a_latebound ()while the parent function has a non-definingInner<'!a> = Inner<'!a>. By eagerly discarding identity uses we don't error on the non-defining use in the parent.r? @BoxyUwU