1 files changed, 43 insertions, 0 deletions
diff --git a/src/test/ui/traits/inheritance/repeated-supertrait-ambig.rs b/src/test/ui/traits/inheritance/repeated-supertrait-ambig.rs
new file mode 100644
index 000000000..727897d20
--- /dev/null
+++ b/src/test/ui/traits/inheritance/repeated-supertrait-ambig.rs
@@ -0,0 +1,43 @@
+// Test a case of a trait which extends the same supertrait twice, but
+// with difference type parameters. Test then that when we don't give
+// enough information to pick between these, no selection is made. In
+// this particular case, the two choices are i64/u64 -- so when we use
+// an integer literal, we wind up falling this literal back to i32.
+// See also `run-pass/trait-repeated-supertrait.rs`.
+
+trait CompareTo<T> {
+    fn same_as(&self, t: T) -> bool;
+}
+
+trait CompareToInts : CompareTo<i64> + CompareTo<u64> {
+}
+
+impl CompareTo<i64> for i64 {
+    fn same_as(&self, t: i64) -> bool { *self == t }
+}
+
+impl CompareTo<u64> for i64 {
+    fn same_as(&self, t: u64) -> bool { *self == (t as i64) }
+}
+
+impl CompareToInts for i64 { }
+
+fn with_obj(c: &dyn CompareToInts) -> bool {
+    c.same_as(22) //~ ERROR `dyn CompareToInts: CompareTo<i32>` is not satisfied
+}
+
+fn with_trait<C:CompareToInts>(c: &C) -> bool {
+    c.same_as(22) //~ ERROR `C: CompareTo<i32>` is not satisfied
+}
+
+fn with_ufcs1<C:CompareToInts>(c: &C) -> bool {
+    <dyn CompareToInts>::same_as(c, 22) //~ ERROR `dyn CompareToInts: CompareTo<i32>` is not satisfi
+}
+
+fn with_ufcs2<C:CompareToInts>(c: &C) -> bool {
+    CompareTo::same_as(c, 22) //~ ERROR `C: CompareTo<i32>` is not satisfied
+}
+
+fn main() {
+    assert_eq!(22_i64.same_as(22), true); //~ ERROR `i64: CompareTo<i32>` is not satisfied
+}