Add test for issue #74761

src/test/ui/type-alias-impl-trait/issue-74761.rs

@@ -0,0 +1,16 @@
+#![feature(member_constraints)]
+#![feature(type_alias_impl_trait)]
+
+pub trait A {
+    type B;
+    fn f(&self) -> Self::B;
+}
+impl<'a, 'b> A for () {
+    //~^ ERROR the lifetime parameter `'a` is not constrained
+    //~| ERROR the lifetime parameter `'b` is not constrained
+    type B = impl core::fmt::Debug;
+
+    fn f(&self) -> Self::B {}
+}
+
+fn main() {}

src/test/ui/type-alias-impl-trait/issue-74761.stderr

@@ -0,0 +1,15 @@
+error[E0207]: the lifetime parameter `'a` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/issue-74761.rs:8:6
+   |
+LL | impl<'a, 'b> A for () {
+   |      ^^ unconstrained lifetime parameter
+
+error[E0207]: the lifetime parameter `'b` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/issue-74761.rs:8:10
+   |
+LL | impl<'a, 'b> A for () {
+   |          ^^ unconstrained lifetime parameter
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0207`.