1 files changed, 22 insertions, 0 deletions
diff --git a/src/test/ui/borrowck/borrowck-swap-mut-base-ptr.rs b/src/test/ui/borrowck/borrowck-swap-mut-base-ptr.rs
new file mode 100644
index 000000000..8170323ef
--- /dev/null
+++ b/src/test/ui/borrowck/borrowck-swap-mut-base-ptr.rs
@@ -0,0 +1,22 @@
+// Test that attempt to swap `&mut` pointer while pointee is borrowed
+// yields an error.
+//
+// Example from compiler/rustc_borrowck/borrowck/README.md
+
+use std::mem::swap;
+
+
+
+fn foo<'a>(mut t0: &'a mut isize,
+           mut t1: &'a mut isize) {
+    let p: &isize = &*t0;     // Freezes `*t0`
+    swap(&mut t0, &mut t1); //~ ERROR cannot borrow `t0`
+    *t1 = 22;
+    p.use_ref();
+}
+
+fn main() {
+}
+
+trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { }  }
+impl<T> Fake for T { }