Rollup merge of #116879 - aliemjay:revert-opaque-bubble, r=oli-obk

revert #114586

Reverts #114586.

cc #116877 (not closing until this gets a beta backport)
fixes #116684
fixes https://github.com/rust-lang/rust/pull/114586#issuecomment-1751967321

r? `@oli-obk` or `@lcnr`

5 files changed, 82 insertions, 3 deletions

diff --git a/tests/ui/impl-trait/equality-in-canonical-query.clone.stderr b/tests/ui/impl-trait/equality-in-canonical-query.clone.stderr
new file mode 100644
index 00000000000..83791f0d3af
--- /dev/null
+++ b/tests/ui/impl-trait/equality-in-canonical-query.clone.stderr
@@ -0,0 +1,29 @@
+error: internal compiler error: no errors encountered even though `delay_span_bug` issued
+
+error: internal compiler error: {OpaqueTypeKey { def_id: DefId(rpit::{opaque#0}), args: [] }: OpaqueTypeDecl { hidden_type: OpaqueHiddenType { span: no-location (#0), ty: Alias(Opaque, AliasTy { args: [], def_id: DefId(foo::{opaque#0}) }) } }}
+   |
+   = 
+           
+
+error: internal compiler error: error performing ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing }, value: ProvePredicate { predicate: Binder { value: ProjectionPredicate(AliasTy { args: [FnDef(DefId(rpit), []), ()], def_id: DefId(ops::function::FnOnce::Output) }, Term::Ty(Alias(Opaque, AliasTy { args: [], def_id: DefId(foo::{opaque#0}) }))), bound_vars: [] } } }
+  --> $DIR/equality-in-canonical-query.rs:19:5
+   |
+LL |     same_output(foo, rpit);
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |
+
+  --> $DIR/equality-in-canonical-query.rs:19:5
+   |
+LL |     same_output(foo, rpit);
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+
+
+
+
+
+
+
+query stack during panic:
+end of query stack
+error: aborting due to 3 previous errors
+
diff --git a/tests/ui/impl-trait/equality-in-canonical-query.rs b/tests/ui/impl-trait/equality-in-canonical-query.rs
new file mode 100644
index 00000000000..672b1eeeab6
--- /dev/null
+++ b/tests/ui/impl-trait/equality-in-canonical-query.rs
@@ -0,0 +1,23 @@
+// issue: #116877
+// revisions: sized clone
+//[sized] check-pass
+
+//[clone] known-bug: #108498
+//[clone] failure-status: 101
+//[clone] normalize-stderr-test: "DefId\(.*?\]::" -> "DefId("
+//[clone] normalize-stderr-test: "(?m)note: .*$" -> ""
+//[clone] normalize-stderr-test: "(?m)^ *\d+: .*\n" -> ""
+//[clone] normalize-stderr-test: "(?m)^ *at .*\n" -> ""
+
+#[cfg(sized)] fn rpit() -> impl Sized {}
+#[cfg(clone)] fn rpit() -> impl Clone {}
+
+fn same_output<Out>(_: impl Fn() -> Out, _: impl Fn() -> Out) {}
+
+pub fn foo() -> impl Sized {
+    same_output(rpit, foo);
+    same_output(foo, rpit);
+    rpit()
+}
+
+fn main () {}
diff --git a/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.current.stderr b/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.current.stderr
index 4b09a9e743b..844103d77a8 100644
--- a/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.current.stderr
+++ b/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.current.stderr
@@ -1,11 +1,17 @@
 error: internal compiler error: no errors encountered even though `delay_span_bug` issued
 
-error: internal compiler error: ambiguity performing ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing }, value: ProvePredicate { predicate: Binder { value: ProjectionPredicate(AliasTy { args: [FnDef(DefId(get_rpit), []), ()], def_id: DefId(ops::function::FnOnce::Output) }, Term::Ty(Alias(Opaque, AliasTy { args: [], def_id: DefId(Opaque::{opaque#0}) }))), bound_vars: [] } } }
+error: internal compiler error: {OpaqueTypeKey { def_id: DefId(get_rpit::{opaque#0}), args: [] }: OpaqueTypeDecl { hidden_type: OpaqueHiddenType { span: no-location (#0), ty: Alias(Opaque, AliasTy { args: [], def_id: DefId(Opaque::{opaque#0}) }) } }}
+   |
+   = 
+           
+
+error: internal compiler error: error performing ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing }, value: ProvePredicate { predicate: Binder { value: ProjectionPredicate(AliasTy { args: [FnDef(DefId(get_rpit), []), ()], def_id: DefId(ops::function::FnOnce::Output) }, Term::Ty(Alias(Opaque, AliasTy { args: [], def_id: DefId(Opaque::{opaque#0}) }))), bound_vars: [] } } }
   --> $DIR/rpit_tait_equality_in_canonical_query.rs:28:5
    |
 LL |     query(get_rpit);
    |     ^^^^^^^^^^^^^^^
    |
+
   --> $DIR/rpit_tait_equality_in_canonical_query.rs:28:5
    |
 LL |     query(get_rpit);
@@ -14,7 +20,10 @@ LL |     query(get_rpit);
 
 
 
+
+
+
 query stack during panic:
 end of query stack
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
diff --git a/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.rs b/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.rs
index 8dccd2ed46f..0f0002f7797 100644
--- a/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.rs
+++ b/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query.rs
@@ -12,7 +12,7 @@
 //[current] known-bug: #108498
 //[current] failure-status: 101
 //[current] normalize-stderr-test: "DefId\(.*?\]::" -> "DefId("
-//[current] normalize-stderr-test: "(?m)^note: .*\n" -> ""
+//[current] normalize-stderr-test: "(?m)note: .*$" -> ""
 //[current] normalize-stderr-test: "(?m)^ *\d+: .*\n" -> ""
 //[current] normalize-stderr-test: "(?m)^ *at .*\n" -> ""
 
diff --git a/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query_2.rs b/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query_2.rs
new file mode 100644
index 00000000000..9d7e647dd94
--- /dev/null
+++ b/tests/ui/type-alias-impl-trait/rpit_tait_equality_in_canonical_query_2.rs
@@ -0,0 +1,18 @@
+// The canonical query `Projection(<get_rpit as FnOnce>::Output = Opaque)`
+// is the *only* site that defines `Opaque` in MIR typeck.
+//
+// check-pass
+
+#![feature(type_alias_impl_trait)]
+
+type Opaque = impl Sized;
+
+fn get_rpit() -> impl Sized {}
+
+fn query(_: impl FnOnce() -> Opaque) {}
+
+fn test(_: Opaque) {
+    query(get_rpit);
+}
+
+fn main() {}