1 files changed, 30 insertions, 0 deletions
diff --git a/tests/ui/regions/region-lifetime-bounds-on-fns-where-clause.rs b/tests/ui/regions/region-lifetime-bounds-on-fns-where-clause.rs
new file mode 100644
index 000000000..d364c4677
--- /dev/null
+++ b/tests/ui/regions/region-lifetime-bounds-on-fns-where-clause.rs
@@ -0,0 +1,30 @@
+fn a<'a, 'b>(x: &mut &'a isize, y: &mut &'b isize) where 'b: 'a {
+    // Note: this is legal because of the `'b:'a` declaration.
+    *x = *y;
+}
+
+fn b<'a, 'b>(x: &mut &'a isize, y: &mut &'b isize) {
+    // Illegal now because there is no `'b:'a` declaration.
+    *x = *y;
+}
+
+fn c<'a,'b>(x: &mut &'a isize, y: &mut &'b isize) {
+    // Here we try to call `foo` but do not know that `'a` and `'b` are
+    // related as required.
+    a(x, y);
+}
+
+fn d() {
+    // 'a and 'b are early bound in the function `a` because they appear
+    // inconstraints:
+    let _: fn(&mut &isize, &mut &isize) = a;
+    //~^ ERROR mismatched types [E0308]
+}
+
+fn e() {
+    // 'a and 'b are late bound in the function `b` because there are
+    // no constraints:
+    let _: fn(&mut &isize, &mut &isize) = b;
+}
+
+fn main() { }