Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/tests/ui/nll/drop-may-dangle.rs b/tests/ui/nll/drop-may-dangle.rs
new file mode 100644
index 000000000..b5531c29b
--- /dev/null
+++ b/tests/ui/nll/drop-may-dangle.rs
@@ -0,0 +1,34 @@
+// Basic test for liveness constraints: the region (`R1`) that appears
+// in the type of `p` includes the points after `&v[0]` up to (but not
+// including) the call to `use_x`. The `else` branch is not included.
+
+// check-pass
+
+#![allow(warnings)]
+#![feature(dropck_eyepatch)]
+
+fn use_x(_: usize) -> bool { true }
+
+fn main() {
+    let mut v = [1, 2, 3];
+    let p: WrapMayDangle<& /* R4 */ usize> = WrapMayDangle { value: &v[0] };
+    if true {
+        // `p` will get dropped at end of this block. However, because of
+        // the `#[may_dangle]` attribute, we do not need to consider R4
+        // live after this point.
+        use_x(*p.value);
+    } else {
+        v[0] += 1;
+        use_x(22);
+    }
+
+    v[0] += 1;
+}
+
+struct WrapMayDangle<T> {
+    value: T
+}
+
+unsafe impl<#[may_dangle] T> Drop for WrapMayDangle<T> {
+    fn drop(&mut self) { }
+}