1 files changed, 68 insertions, 0 deletions
diff --git a/src/test/ui/traits/issue-33140-hack-boundaries.stderr b/src/test/ui/traits/issue-33140-hack-boundaries.stderr
new file mode 100644
index 000000000..62cfca545
--- /dev/null
+++ b/src/test/ui/traits/issue-33140-hack-boundaries.stderr
@@ -0,0 +1,68 @@
+error[E0119]: conflicting implementations of trait `Trait1` for type `(dyn std::marker::Send + 'static)`
+  --> $DIR/issue-33140-hack-boundaries.rs:18:1
+   |
+LL | impl Trait1 for dyn Send {}
+   | ------------------------ first implementation here
+LL | impl Trait1 for dyn Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+
+error[E0751]: found both positive and negative implementation of trait `Trait2` for type `(dyn std::marker::Send + 'static)`:
+  --> $DIR/issue-33140-hack-boundaries.rs:25:1
+   |
+LL | impl Trait2 for dyn Send {}
+   | ------------------------ positive implementation here
+LL | impl !Trait2 for dyn Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ negative implementation here
+
+error[E0119]: conflicting implementations of trait `Trait3<(dyn std::marker::Sync + 'static)>` for type `(dyn std::marker::Send + 'static)`
+  --> $DIR/issue-33140-hack-boundaries.rs:32:1
+   |
+LL | impl Trait3<dyn Sync> for dyn Send {}
+   | ---------------------------------- first implementation here
+LL | impl Trait3<dyn Sync> for dyn Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+
+error[E0119]: conflicting implementations of trait `Trait4a` for type `(dyn std::marker::Send + 'static)`
+  --> $DIR/issue-33140-hack-boundaries.rs:39:1
+   |
+LL | impl<T: ?Sized> Trait4a for T {}
+   | ----------------------------- first implementation here
+LL | impl Trait4a for dyn Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+
+error[E0119]: conflicting implementations of trait `Trait4b` for type `()`
+  --> $DIR/issue-33140-hack-boundaries.rs:46:1
+   |
+LL | impl Trait4b for () {}
+   | ------------------- first implementation here
+LL | impl Trait4b for () {}
+   | ^^^^^^^^^^^^^^^^^^^ conflicting implementation for `()`
+
+error[E0119]: conflicting implementations of trait `Trait4c` for type `(dyn Trait1 + std::marker::Send + 'static)`
+  --> $DIR/issue-33140-hack-boundaries.rs:53:1
+   |
+LL | impl Trait4c for dyn Trait1 + Send {}
+   | ---------------------------------- first implementation here
+LL | impl Trait4c for dyn Trait1 + Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Trait1 + std::marker::Send + 'static)`
+
+error[E0119]: conflicting implementations of trait `Trait4d` for type `dyn std::marker::Send`
+  --> $DIR/issue-33140-hack-boundaries.rs:60:1
+   |
+LL | impl<'a> Trait4d for dyn Send + 'a {}
+   | ---------------------------------- first implementation here
+LL | impl<'a> Trait4d for dyn Send + 'a {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `dyn std::marker::Send`
+
+error[E0119]: conflicting implementations of trait `Trait5` for type `(dyn std::marker::Send + 'static)`
+  --> $DIR/issue-33140-hack-boundaries.rs:67:1
+   |
+LL | impl Trait5 for dyn Send {}
+   | ------------------------ first implementation here
+LL | impl Trait5 for dyn Send where u32: Copy {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+
+error: aborting due to 8 previous errors
+
+Some errors have detailed explanations: E0119, E0751.
+For more information about an error, try `rustc --explain E0119`.