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-rw-r--r--src/test/ui/regions/regions-ret-borrowed.rs20
1 files changed, 20 insertions, 0 deletions
diff --git a/src/test/ui/regions/regions-ret-borrowed.rs b/src/test/ui/regions/regions-ret-borrowed.rs
new file mode 100644
index 000000000..bdb0341c9
--- /dev/null
+++ b/src/test/ui/regions/regions-ret-borrowed.rs
@@ -0,0 +1,20 @@
+// Ensure that you cannot use generic types to return a region outside
+// of its bound. Here, in the `return_it()` fn, we call with() but
+// with R bound to &isize from the return_it. Meanwhile, with()
+// provides a value that is only good within its own stack frame. This
+// used to successfully compile because we failed to account for the
+// fact that fn(x: &isize) rebound the region &.
+
+fn with<R, F>(f: F) -> R where F: FnOnce(&isize) -> R {
+ f(&3)
+}
+
+fn return_it<'a>() -> &'a isize {
+ with(|o| o)
+ //~^ ERROR lifetime may not live long enough
+}
+
+fn main() {
+ let x = return_it();
+ println!("foo={}", *x);
+}