8 files changed, 98 insertions, 5 deletions
diff --git a/src/test/ui/coherence/auxiliary/trait-with-const-param.rs b/src/test/ui/coherence/auxiliary/trait-with-const-param.rs
new file mode 100644
index 000000000..a44eb14f8
--- /dev/null
+++ b/src/test/ui/coherence/auxiliary/trait-with-const-param.rs
@@ -0,0 +1 @@
+pub trait Trait<const N: usize, T> {}
diff --git a/src/test/ui/coherence/coherence-negative-outlives-lifetimes.rs b/src/test/ui/coherence/coherence-negative-outlives-lifetimes.rs
index 159788b1b..3acf0d8d3 100644
--- a/src/test/ui/coherence/coherence-negative-outlives-lifetimes.rs
+++ b/src/test/ui/coherence/coherence-negative-outlives-lifetimes.rs
@@ -1,12 +1,17 @@
-#![feature(negative_impls)]
+// revisions: stock with_negative_coherence
+//[with_negative_coherence] check-pass
 
-// FIXME: this should compile
+#![feature(negative_impls)]
+#![cfg_attr(with_negative_coherence, feature(with_negative_coherence))]
 
 trait MyPredicate<'a> {}
-impl<'a, T> !MyPredicate<'a> for &T where T: 'a {}
+
+impl<'a, T> !MyPredicate<'a> for &'a T where T: 'a {}
+
 trait MyTrait<'a> {}
+
 impl<'a, T: MyPredicate<'a>> MyTrait<'a> for T {}
 impl<'a, T> MyTrait<'a> for &'a T {}
-//~^ ERROR: conflicting implementations of trait `MyTrait<'_>` for type `&_`
+//[stock]~^ ERROR: conflicting implementations of trait `MyTrait<'_>` for type `&_`
 
 fn main() {}
diff --git a/src/test/ui/coherence/coherence-negative-outlives-lifetimes.stderr b/src/test/ui/coherence/coherence-negative-outlives-lifetimes.stock.stderr
index 263bd19b4..097cc4e0f 100644
--- a/src/test/ui/coherence/coherence-negative-outlives-lifetimes.stderr
+++ b/src/test/ui/coherence/coherence-negative-outlives-lifetimes.stock.stderr
@@ -1,5 +1,5 @@
 error[E0119]: conflicting implementations of trait `MyTrait<'_>` for type `&_`
-  --> $DIR/coherence-negative-outlives-lifetimes.rs:9:1
+  --> $DIR/coherence-negative-outlives-lifetimes.rs:14:1
    |
 LL | impl<'a, T: MyPredicate<'a>> MyTrait<'a> for T {}
    | ---------------------------------------------- first implementation here
diff --git a/src/test/ui/coherence/const-generics-orphan-check-ok.rs b/src/test/ui/coherence/const-generics-orphan-check-ok.rs
new file mode 100644
index 000000000..217e8aed2
--- /dev/null
+++ b/src/test/ui/coherence/const-generics-orphan-check-ok.rs
@@ -0,0 +1,28 @@
+// check-pass
+// aux-build:trait-with-const-param.rs
+extern crate trait_with_const_param;
+use trait_with_const_param::*;
+
+// Trivial case, const param after local type.
+struct Local1;
+impl<const N: usize, T> Trait<N, T> for Local1 {}
+
+// Concrete consts behave the same as foreign types,
+// so this also trivially works.
+impl Trait<3, Local1> for i32 {}
+
+// This case isn't as trivial as we would forbid type
+// parameters here, we do allow const parameters though.
+//
+// The reason that type parameters are forbidden for
+// `impl<T> Trait<T, LocalInA> for i32 {}` is that another
+// downstream crate can add `impl<T> Trait<LocalInB, T> for i32`.
+// As these two impls would overlap we forbid any impls which
+// have a type parameter in front of a local type.
+//
+// With const parameters this issue does not exist as there are no
+// constants local to another downstream crate.
+struct Local2;
+impl<const N: usize> Trait<N, Local2> for i32 {}
+
+fn main() {}
diff --git a/src/test/ui/coherence/issue-100191-2.rs b/src/test/ui/coherence/issue-100191-2.rs
new file mode 100644
index 000000000..1c8316f87
--- /dev/null
+++ b/src/test/ui/coherence/issue-100191-2.rs
@@ -0,0 +1,12 @@
+//~ ERROR overflow evaluating the requirement `T: Trait<_>`
+
+#![feature(specialization, with_negative_coherence)]
+#![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/coherence/issue-100191-2.stderr b/src/test/ui/coherence/issue-100191-2.stderr
new file mode 100644
index 000000000..d50c220bc
--- /dev/null
+++ b/src/test/ui/coherence/issue-100191-2.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_100191_2`)
+note: required for `T` to implement `Trait<_>`
+  --> $DIR/issue-100191-2.rs:8:20
+   |
+LL | default impl<T, U> Trait<T> for U {}
+   |                    ^^^^^^^^     ^
+   = note: 128 redundant requirements hidden
+   = note: required for `T` to implement `Trait<_>`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0275`.
diff --git a/src/test/ui/coherence/issue-100191.rs b/src/test/ui/coherence/issue-100191.rs
new file mode 100644
index 000000000..e8597fde5
--- /dev/null
+++ b/src/test/ui/coherence/issue-100191.rs
@@ -0,0 +1,21 @@
+#![crate_type = "lib"]
+#![feature(specialization, with_negative_coherence)]
+#![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/coherence/issue-100191.stderr b/src/test/ui/coherence/issue-100191.stderr
new file mode 100644
index 000000000..1adb0f1e4
--- /dev/null
+++ b/src/test/ui/coherence/issue-100191.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-100191.rs:18:6
+   |
+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`.