Auto merge of #133818 - matthiaskrgr:rollup-iav1wq7, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #132937 (a release operation synchronizes with an acquire operation)
 - #133681 (improve TagEncoding::Niche docs, sanity check, and UB checks)
 - #133726 (Add `core::arch::breakpoint` and test)
 - #133768 (Remove `generic_associated_types_extended` feature gate)
 - #133811 ([AIX] change AIX default codemodel=large)
 - #133812 (Update wasm-component-ld to 0.5.11)
 - #133813 (compiletest: explain that UI tests are expected not to compile by default)

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs

@@ -328,10 +328,7 @@ pub fn dyn_compatibility_violations_for_assoc_item(
             .collect(),
         // Associated types can only be dyn-compatible if they have `Self: Sized` bounds.
         ty::AssocKind::Type => {
-            if !tcx.features().generic_associated_types_extended()
-                && !tcx.generics_of(item.def_id).is_own_empty()
-                && !item.is_impl_trait_in_trait()
-            {
+            if !tcx.generics_of(item.def_id).is_own_empty() && !item.is_impl_trait_in_trait() {
                 vec![DynCompatibilityViolation::GAT(item.name, item.ident(tcx).span)]
             } else {
                 // We will permit associated types if they are explicitly mentioned in the trait object.

compiler/rustc_trait_selection/src/traits/project.rs

@@ -14,7 +14,7 @@ use rustc_middle::traits::select::OverflowError;
 use rustc_middle::traits::{BuiltinImplSource, ImplSource, ImplSourceUserDefinedData};
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
 use rustc_middle::ty::fold::TypeFoldable;
-use rustc_middle::ty::visit::{MaxUniverse, TypeVisitable, TypeVisitableExt};
+use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{self, Term, Ty, TyCtxt, TypingMode, Upcast};
 use rustc_middle::{bug, span_bug};
 use rustc_span::symbol::sym;
@@ -179,35 +179,11 @@ pub(super) fn poly_project_and_unify_term<'cx, 'tcx>(
 ) -> ProjectAndUnifyResult<'tcx> {
     let infcx = selcx.infcx;
     let r = infcx.commit_if_ok(|_snapshot| {
-        let old_universe = infcx.universe();
         let placeholder_predicate = infcx.enter_forall_and_leak_universe(obligation.predicate);
-        let new_universe = infcx.universe();
 
         let placeholder_obligation = obligation.with(infcx.tcx, placeholder_predicate);
         match project_and_unify_term(selcx, &placeholder_obligation) {
             ProjectAndUnifyResult::MismatchedProjectionTypes(e) => Err(e),
-            ProjectAndUnifyResult::Holds(obligations)
-                if old_universe != new_universe
-                    && selcx.tcx().features().generic_associated_types_extended() =>
-            {
-                // If the `generic_associated_types_extended` feature is active, then we ignore any
-                // obligations references lifetimes from any universe greater than or equal to the
-                // universe just created. Otherwise, we can end up with something like `for<'a> I: 'a`,
-                // which isn't quite what we want. Ideally, we want either an implied
-                // `for<'a where I: 'a> I: 'a` or we want to "lazily" check these hold when we
-                // instantiate concrete regions. There is design work to be done here; until then,
-                // however, this allows experimenting potential GAT features without running into
-                // well-formedness issues.
-                let new_obligations = obligations
-                    .into_iter()
-                    .filter(|obligation| {
-                        let mut visitor = MaxUniverse::new();
-                        obligation.predicate.visit_with(&mut visitor);
-                        visitor.max_universe() < new_universe
-                    })
-                    .collect();
-                Ok(ProjectAndUnifyResult::Holds(new_obligations))
-            }
             other => Ok(other),
         }
     });

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -626,7 +626,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         for assoc_type in assoc_types {
             let defs: &ty::Generics = tcx.generics_of(assoc_type);
 
-            if !defs.own_params.is_empty() && !tcx.features().generic_associated_types_extended() {
+            if !defs.own_params.is_empty() {
                 tcx.dcx().span_delayed_bug(
                     obligation.cause.span,
                     "GATs in trait object shouldn't have been considered",