bors 9ab0749ce3 Auto merge of #112875 - compiler-errors:negative-coherence-rework, r=lcnr ... Rework negative coherence to properly consider impls that only partly overlap This PR implements a modified negative coherence that handles impls that only have partial overlap. It does this by: 1. taking both impl trait refs, instantiating them with infer vars 2. equating both trait refs 3. taking the equated trait ref (which represents the two impls' intersection), and resolving any vars 4. plugging all remaining infer vars with placeholder types these placeholder-plugged trait refs can then be used normally with the new trait solver, since we no longer have to worry about the issue with infer vars in param-envs. We use the **new trait solver** to reason correctly about unnormalized trait refs (due to deferred projection equality), since this avoid having to normalize anything under param-envs with infer vars in them. This PR then additionally: * removes the `FnPtr` knowable hack by implementing proper negative `FnPtr` trait bounds for rigid types. --- An example: Consider these two partially overlapping impls: ``` impl<T, U> PartialEq<&U> for &T where T: PartialEq<U> {} impl<F> PartialEq<F> for F where F: FnPtr {} ``` Under the old algorithm, we would take one of these impls and replace it with infer vars, then try unifying it with the other impl under identity substitutions. This is not possible in either direction, since it either sets `T = U`, or tries to equate `F = &?0`. Under the new algorithm, we try to unify `?0: PartialEq<?0>` with `&?1: PartialEq<&?2>`. This gives us `?0 = &?1 = &?2` and thus `?1 = ?2`. The intersection of these two trait refs therefore looks like: `&?1: PartialEq<&?1>`. After plugging this with placeholders, we get a trait ref that looks like `&!0: PartialEq<&!0>`, with the first impl having substs `?T = ?U = !0` and the second having substs `?F = &!0`[^1]. Then we can take the param-env from the first impl, and try to prove the negated where clause of the second. We know that `&!0: !FnPtr` never holds, since it's a rigid type that is also not a fn ptr, we successfully detect that these impls may never overlap. [^1]: For the purposes of this example, I just ignored lifetimes, since it doesn't really matter.		2023-10-26 10:57:21 +00:00
..
alias-liveness	Add some unsoundness tests for opaques capturing hidden regions not in substs	2023-10-14 13:26:30 +00:00
auxiliary
diagnostics
explicit-generic-args-with-impl-trait
in-trait	Remove incomplete features from RPITIT/AFIT tests	2023-10-24 15:27:06 +00:00
issues	s/generator/coroutine/	2023-10-20 21:14:01 +00:00
multiple-lifetimes
rpit	check for non-defining uses of RPIT	2023-08-14 15:25:20 +02:00
arg-position-impl-trait-too-long.rs
arg-position-impl-trait-too-long.stderr	Tweak wording of type errors involving type params	2023-10-18 23:53:18 +00:00
associated-impl-trait-type-generic-trait.rs
associated-impl-trait-type-trivial.rs
associated-impl-trait-type.rs
async_scope_creep.rs	Remove DefiningAnchor::Bubble from opaque wf check	2023-10-16 15:50:31 +00:00
auto-trait-coherence.next.stderr	explicitly handle auto trait leakage in coherence	2023-10-13 09:42:51 +00:00
auto-trait-coherence.old.stderr	explicitly handle auto trait leakage in coherence	2023-10-13 09:42:51 +00:00
auto-trait-coherence.rs	explicitly handle auto trait leakage in coherence	2023-10-13 09:42:51 +00:00
auto-trait-leak2.rs	Revert "Suggest using Arc on !Send/!Sync types"	2023-08-28 03:16:48 -07:00
auto-trait-leak2.stderr	Revert "Suggest using Arc on !Send/!Sync types"	2023-08-28 03:16:48 -07:00
auto-trait-leak-rpass.rs
auto-trait-leak.rs	More precisely detect cycle errors from type_of on opaque	2023-08-27 22:03:16 +00:00
auto-trait-leak.stderr	More precisely detect cycle errors from type_of on opaque	2023-08-27 22:03:16 +00:00
autoderef.rs	Consider a goal as NOT changed if its response is identity modulo regions	2023-07-27 04:00:49 +00:00
bound-normalization-fail.rs	Stabilize impl_trait_projections	2023-09-08 03:45:36 +00:00
bound-normalization-fail.stderr	Stabilize impl_trait_projections	2023-09-08 03:45:36 +00:00
bound-normalization-pass.rs
bounds_regression.rs	s/generator/coroutine/	2023-10-20 21:14:01 +00:00
can-return-unconstrained-closure.rs
capture-lifetime-not-in-hir.rs	Stabilize impl_trait_projections	2023-09-08 03:45:36 +00:00
capture-lifetime-not-in-hir.stderr	Stabilize impl_trait_projections	2023-09-08 03:45:36 +00:00
closure-calling-parent-fn.rs
closure-in-impl-trait-arg.rs
closure-in-impl-trait.rs
coherence-treats-tait-ambig.current.stderr
coherence-treats-tait-ambig.rs	update tests	2023-09-21 08:17:58 +02:00
coherence-treats-tait-ambig.stderr	update tests	2023-09-21 08:17:58 +02:00
cross-return-site-inference.rs	Reorder fullfillment errors to keep more interesting ones first	2023-10-04 02:04:14 +00:00
cross-return-site-inference.stderr	Show suggestion for <SelfTy as Trait>::assoc_fn in more cases and fmt code	2023-10-04 02:04:14 +00:00
deduce-signature-from-supertrait.rs	Require TAITs to be mentioned in the signatures of functions that register hidden types for them	2023-07-07 13:13:18 +00:00
defined-by-trait-resolution.rs	allow opaques to be defined by trait queries	2023-07-14 12:35:33 +00:00
deprecated_annotation.rs
divergence.rs
does-not-live-long-enough.rs
does-not-live-long-enough.stderr
dont-suggest-box-on-empty-else-arm.rs
dont-suggest-box-on-empty-else-arm.stderr
dyn-trait-elided-two-inputs-assoc.rs
dyn-trait-elided-two-inputs-param.rs
dyn-trait-elided-two-inputs-ref-assoc.rs
dyn-trait-elided-two-inputs-ref-param.rs
dyn-trait-return-should-be-impl-trait.rs
dyn-trait-return-should-be-impl-trait.stderr
equal-hidden-lifetimes.rs
equality2.rs
equality2.stderr
equality-in-canonical-query.clone.stderr	revert rust-lang/rust#114586	2023-10-18 06:19:04 +00:00
equality-in-canonical-query.rs	revert rust-lang/rust#114586	2023-10-18 06:19:04 +00:00
equality-rpass.rs
equality-rpass.stderr
equality.rs
equality.stderr
erased-regions-in-hidden-ty.current.stderr	Let's see what those opaque types actually are	2023-10-23 16:18:35 -04:00
erased-regions-in-hidden-ty.next.stderr	Let's see what those opaque types actually are	2023-10-23 16:18:35 -04:00
erased-regions-in-hidden-ty.rs	Let's see what those opaque types actually are	2023-10-23 16:18:35 -04:00
example-calendar.rs
example-st.rs
extra-impl-in-trait-impl.fixed
extra-impl-in-trait-impl.rs
extra-impl-in-trait-impl.stderr
extra-item.rs
extra-item.stderr
fallback_inference.rs
fallback_inference.stderr
fallback.rs
feature-self-return-type.rs	Stabilize impl_trait_projections	2023-09-08 03:45:36 +00:00
feature-self-return-type.stderr	Stabilize impl_trait_projections	2023-09-08 03:45:36 +00:00
fresh-lifetime-from-bare-trait-obj-114664.rs	Record binder for bare trait object in LifetimeCollectVisitor	2023-08-11 03:15:41 +00:00
fresh-lifetime-from-bare-trait-obj-114664.stderr	Add a note to duplicate diagnostics	2023-10-05 01:04:41 +00:00
generic-with-implicit-hrtb-without-dyn.edition2015.stderr
generic-with-implicit-hrtb-without-dyn.edition2021.stderr
generic-with-implicit-hrtb-without-dyn.rs
hidden-lifetimes.rs
hidden-lifetimes.stderr
hidden-type-is-opaque-2.rs	Fix invalid suggestion for mismatched types in closure arguments	2023-07-30 17:15:55 +02:00
hidden-type-is-opaque-2.stderr	Fix invalid suggestion for mismatched types in closure arguments	2023-07-30 17:15:55 +02:00
hidden-type-is-opaque.rs
impl_fn_associativity.rs
impl_trait_projections.rs
impl_trait_projections.stderr
impl-fn-hrtb-bounds-2.rs
impl-fn-hrtb-bounds-2.stderr
impl-fn-hrtb-bounds.rs
impl-fn-hrtb-bounds.stderr
impl-fn-parsing-ambiguities.rs
impl-fn-parsing-ambiguities.stderr
impl-fn-predefined-lifetimes.rs
impl-fn-predefined-lifetimes.stderr
impl-generic-mismatch-ab.rs
impl-generic-mismatch-ab.stderr
impl-generic-mismatch.rs
impl-generic-mismatch.stderr
impl-subtyper2.rs	move subtyper change reveal_all	2023-10-05 18:56:30 +03:00
impl-subtyper.rs	move subtyper change reveal_all	2023-10-05 18:56:30 +03:00
impl-trait-in-macro.rs
impl-trait-in-macro.stderr
impl-trait-plus-priority.rs
impl-trait-plus-priority.stderr
in-assoc-type-unconstrained.rs
in-assoc-type-unconstrained.stderr
in-assoc-type.rs	Require TAITs to be mentioned in the signatures of functions that register hidden types for them	2023-07-07 13:13:18 +00:00
in-assoc-type.stderr	Require TAITs to be mentioned in the signatures of functions that register hidden types for them	2023-07-07 13:13:18 +00:00
issue-35668.rs
issue-35668.stderr
issue-36792.rs
issue-46959.rs
issue-49556.rs
issue-49579.rs
issue-49685.rs
issue-51185.rs
issue-54966.rs
issue-54966.stderr
issue-55872-1.rs
issue-55872-1.stderr
issue-55872-2.rs	Bless tests.	2023-09-23 13:47:30 +00:00
issue-55872-2.stderr	Add a note to duplicate diagnostics	2023-10-05 01:04:41 +00:00
issue-55872-3.rs	Remove compare mode	2023-07-03 21:40:04 +00:00
issue-55872-3.stderr	adjust how closure/generator types and rvalues are printed	2023-09-21 22:20:58 +02:00
issue-55872.rs
issue-55872.stderr
issue-56445.rs
issue-68532.rs
issue-72911.rs
issue-72911.stderr
issue-86465.rs	Revert "Auto merge of #102417 - oli-obk:opaque_lifetimes2, r=jackh726"	2023-08-30 11:06:46 +00:00
issue-86465.stderr	Revert "Auto merge of #102417 - oli-obk:opaque_lifetimes2, r=jackh726"	2023-08-30 11:06:46 +00:00
issue-87450.rs
issue-87450.stderr
issue-99073-2.rs	check for non-defining uses of RPIT	2023-08-14 15:25:20 +02:00
issue-99073-2.stderr	check for non-defining uses of RPIT	2023-08-14 15:25:20 +02:00
issue-99073.rs	check for non-defining uses of RPIT	2023-08-14 15:25:20 +02:00
issue-99073.stderr	adjust how closure/generator types and rvalues are printed	2023-09-21 22:20:58 +02:00
issue-99642-2.rs
issue-99642.rs
issue-99914.rs
issue-99914.stderr
issue-100075-2.rs
issue-100075-2.stderr
issue-100075.rs
issue-100075.stderr
issue-100187.rs
issue-102605.rs
issue-102605.stderr	Check entry type as part of item type checking.	2023-07-15 22:02:16 +00:00
issue-103181-1.current.stderr
issue-103181-1.next.stderr
issue-103181-1.rs
issue-103181-2.rs	More precisely detect cycle errors from type_of on opaque	2023-08-27 22:03:16 +00:00
issue-103181-2.stderr	More precisely detect cycle errors from type_of on opaque	2023-08-27 22:03:16 +00:00
issue-103599.rs
issue-103599.stderr
issue-108591.rs	Revert "Auto merge of #102417 - oli-obk:opaque_lifetimes2, r=jackh726"	2023-08-30 11:06:46 +00:00
issue-108592.rs	Revert "Auto merge of #102417 - oli-obk:opaque_lifetimes2, r=jackh726"	2023-08-30 11:06:46 +00:00
lifetime-ambiguity-regression.rs	Paper over an accidental regression	2023-09-14 15:16:48 +00:00
lifetimes2.rs
lifetimes.rs	s/generator/coroutine/	2023-10-20 21:14:01 +00:00
mapping-duplicated-lifetimes-issue-114597.rs	add'l test	2023-08-08 09:39:59 +00:00
method-suggestion-no-duplication.rs
method-suggestion-no-duplication.stderr
multiple-defining-usages-in-body.rs
multiple-defining-usages-in-body.stderr
must_outlive_least_region_or_bound.rs
must_outlive_least_region_or_bound.stderr	remove trailing dots	2023-10-08 10:06:17 +00:00
needs_least_region_or_bound.rs
negative-reasoning.rs
negative-reasoning.stderr	Make things work by using the new solver	2023-10-23 23:35:27 +00:00
nested_impl_trait.rs	Tweak wording of E0562	2023-10-04 19:51:43 +00:00
nested_impl_trait.stderr	Tweak wording of E0562	2023-10-04 19:51:43 +00:00
nested-return-type2-tait2.rs	Remove DefiningAnchor::Bubble from opaque wf check	2023-10-16 15:50:31 +00:00
nested-return-type2-tait2.stderr	Remove DefiningAnchor::Bubble from opaque wf check	2023-10-16 15:50:31 +00:00
nested-return-type2-tait3.rs	Remove DefiningAnchor::Bubble from opaque wf check	2023-10-16 15:50:31 +00:00
nested-return-type2-tait3.stderr	Remove DefiningAnchor::Bubble from opaque wf check	2023-10-16 15:50:31 +00:00
nested-return-type2-tait.rs
nested-return-type2-tait.stderr
nested-return-type2.rs
nested-return-type3-tait2.rs
nested-return-type3-tait2.stderr
nested-return-type3-tait3.rs
nested-return-type3-tait3.stderr
nested-return-type3-tait.rs
nested-return-type3-tait.stderr
nested-return-type3.rs
nested-return-type4.rs
nested-return-type4.stderr	adjust how closure/generator types and rvalues are printed	2023-09-21 22:20:58 +02:00
nested-return-type.rs
nested-rpit-hrtb-2.rs	don't ICE on higher ranked hidden types	2023-08-04 15:11:09 +00:00
nested-rpit-hrtb-2.stderr	don't ICE on higher ranked hidden types	2023-08-04 15:11:09 +00:00
nested-rpit-hrtb.rs
nested-rpit-hrtb.stderr
nested-rpit-with-anonymous-lifetimes.rs
nesting.rs
no-method-suggested-traits.rs
no-method-suggested-traits.stderr
no-trait.rs
no-trait.stderr
normalize-opaque-with-bound-vars.rs
normalize-tait-in-const.rs	update tests, adding known-bug	2023-07-27 15:51:02 +00:00
normalize-tait-in-const.stderr	bless the known-bug tests	2023-09-20 03:02:14 +00:00
object-unsafe-trait-in-return-position-dyn-trait.rs
object-unsafe-trait-in-return-position-dyn-trait.stderr
object-unsafe-trait-in-return-position-impl-trait.rs
object-unsafe-trait-in-return-position-impl-trait.stderr
opaque-cast-field-access-in-future.rs	Only prevent field projections into opaque types, not types containing opaque types	2023-09-25 17:41:08 +00:00
opaque-cast-field-access-in-future.stderr	Reorder fullfillment errors to keep more interesting ones first	2023-10-04 02:04:14 +00:00
point-to-type-err-cause-on-impl-trait-return.rs
point-to-type-err-cause-on-impl-trait-return.stderr
printing-binder.rs
printing-binder.stderr
private_unused.rs
projection-mismatch-in-impl-where-clause.rs
projection-mismatch-in-impl-where-clause.stderr
projection.rs
question_mark.rs
recursive-auto-trait.rs	deal with opaque types without cycling	2023-07-06 11:37:21 +02:00
recursive-coroutine.rs	Rename lots of files that had generator in their name	2023-10-20 21:14:02 +00:00
recursive-coroutine.stderr	Rename lots of files that had generator in their name	2023-10-20 21:14:02 +00:00
recursive-impl-trait-type-direct.rs
recursive-impl-trait-type-indirect.rs	s/generator/coroutine/	2023-10-20 21:14:01 +00:00
recursive-impl-trait-type-indirect.stderr	s/generator/coroutine/	2023-10-20 21:14:01 +00:00
recursive-impl-trait-type-through-non-recursive.rs
recursive-impl-trait-type-through-non-recursive.stderr
recursive-type-alias-impl-trait-declaration-too-subtle-2.rs
recursive-type-alias-impl-trait-declaration-too-subtle.rs
recursive-type-alias-impl-trait-declaration-too-subtle.stderr
recursive-type-alias-impl-trait-declaration.rs
recursive-type-alias-impl-trait-declaration.stderr
region-escape-via-bound-contravariant-closure.rs
region-escape-via-bound-contravariant.rs
region-escape-via-bound.rs
region-escape-via-bound.stderr
return-position-impl-trait-minimal.rs
reveal-during-codegen.rs	Normalize opaques during codegen in new solver	2023-07-07 16:02:25 +00:00
rpit-assoc-pair-with-lifetime.rs
rpit-not-sized.rs
rpit-not-sized.stderr
static-lifetime-return-position-impl-trait.rs	Stabilize AFIT and RPITIT	2023-10-13 21:01:36 +00:00
static-return-lifetime-infered.rs
static-return-lifetime-infered.stderr	adjust how closure/generator types and rvalues are printed	2023-09-21 22:20:58 +02:00
suggest-calling-rpit-closure.rs
suggest-calling-rpit-closure.stderr
trait_resolution.rs
trait_type.rs
trait_type.stderr
two_tait_defining_each_other2.rs
two_tait_defining_each_other2.stderr
two_tait_defining_each_other3.rs
two_tait_defining_each_other3.stderr
two_tait_defining_each_other.rs
two_tait_defining_each_other.stderr
type_parameters_captured.rs
type_parameters_captured.stderr	remove trailing dots	2023-10-08 10:06:17 +00:00
type-alias-generic-param.rs
type-alias-impl-trait-in-fn-body.rs
type-arg-mismatch-due-to-impl-trait.rs
type-arg-mismatch-due-to-impl-trait.stderr
unactionable_diagnostic.fixed	remove trailing dots	2023-10-08 10:06:17 +00:00
unactionable_diagnostic.rs	remove trailing dots	2023-10-08 10:06:17 +00:00
unactionable_diagnostic.stderr	remove trailing dots	2023-10-08 10:06:17 +00:00
universal_hrtb_anon.rs
universal_hrtb_named.rs
universal_in_adt_in_parameters.rs
universal_in_impl_trait_in_parameters.rs
universal_in_trait_defn_parameters.rs
universal_multiple_bounds.rs
universal_wrong_bounds.rs
universal_wrong_bounds.stderr
universal_wrong_hrtb.rs
universal_wrong_hrtb.stderr
universal-mismatched-type.rs
universal-mismatched-type.stderr	Tweak wording of type errors involving type params	2023-10-18 23:53:18 +00:00
universal-two-impl-traits.rs
universal-two-impl-traits.stderr
unsafety-checking-cycle.rs
variance.rs	Test variances of opaque captures	2023-08-28 01:05:34 +00:00
variance.stderr	Test variances of opaque captures	2023-08-28 01:05:34 +00:00
wf-eval-order.rs
where-allowed-2.rs
where-allowed-2.stderr	Reorder fullfillment errors to keep more interesting ones first	2023-10-04 02:04:14 +00:00
where-allowed.rs	Stabilize AFIT and RPITIT	2023-10-13 21:01:36 +00:00
where-allowed.stderr	Stabilize AFIT and RPITIT	2023-10-13 21:01:36 +00:00
xcrate_simple.rs
xcrate.rs