Delay a bug when failed to normalize trait ref during specialization

4 files changed, 58 insertions, 0 deletions

diff --git a/src/test/ui/specialization/issue-43037.rs b/src/test/ui/specialization/issue-43037.rs
new file mode 100644
index 00000000000..c49119f9c09
--- /dev/null
+++ b/src/test/ui/specialization/issue-43037.rs
@@ -0,0 +1,20 @@
+#![feature(specialization)]
+#![allow(incomplete_features)]
+
+trait X {}
+trait Y: X {}
+trait Z {
+    type Assoc: Y;
+}
+struct A<T>(T);
+
+impl<T> Y for T where T: X {}
+impl<T: X> Z for A<T> {
+    type Assoc = T;
+}
+
+// this impl is invalid, but causes an ICE anyway
+impl<T> From<<A<T> as Z>::Assoc> for T {}
+//~^ ERROR type parameter `T` must be used as the type parameter for some local type (e.g., `MyStruct<T>`)
+
+fn main() {}
diff --git a/src/test/ui/specialization/issue-43037.stderr b/src/test/ui/specialization/issue-43037.stderr
new file mode 100644
index 00000000000..4249cd89477
--- /dev/null
+++ b/src/test/ui/specialization/issue-43037.stderr
@@ -0,0 +1,12 @@
+error[E0210]: type parameter `T` must be used as the type parameter for some local type (e.g., `MyStruct<T>`)
+  --> $DIR/issue-43037.rs:17:6
+   |
+LL | impl<T> From<<A<T> as Z>::Assoc> for T {}
+   |      ^ type parameter `T` must be used as the type parameter for some local type
+   |
+   = note: implementing a foreign trait is only possible if at least one of the types for which it is implemented is local
+   = note: only traits defined in the current crate can be implemented for a type parameter
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0210`.
diff --git a/src/test/ui/specialization/issue-45814.rs b/src/test/ui/specialization/issue-45814.rs
new file mode 100644
index 00000000000..8ee5d3e2e58
--- /dev/null
+++ b/src/test/ui/specialization/issue-45814.rs
@@ -0,0 +1,12 @@
+//~ ERROR overflow evaluating the requirement `T: Trait<_>`
+
+#![feature(specialization)]
+#![allow(incomplete_features)]
+
+pub trait Trait<T> {}
+
+default impl<T, U> Trait<T> for U {}
+
+impl<T> Trait<<T as Iterator>::Item> for T {}
+
+fn main() {}
diff --git a/src/test/ui/specialization/issue-45814.stderr b/src/test/ui/specialization/issue-45814.stderr
new file mode 100644
index 00000000000..ab6adf477c9
--- /dev/null
+++ b/src/test/ui/specialization/issue-45814.stderr
@@ -0,0 +1,14 @@
+error[E0275]: overflow evaluating the requirement `T: Trait<_>`
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_45814`)
+note: required because of the requirements on the impl of `Trait<_>` for `T`
+  --> $DIR/issue-45814.rs:8:20
+   |
+LL | default impl<T, U> Trait<T> for U {}
+   |                    ^^^^^^^^     ^
+   = note: 128 redundant requirements hidden
+   = note: required because of the requirements on the impl of `Trait<_>` for `T`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0275`.