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-rw-r--r--src/test/ui/nll/drop-may-dangle.rs34
1 files changed, 34 insertions, 0 deletions
diff --git a/src/test/ui/nll/drop-may-dangle.rs b/src/test/ui/nll/drop-may-dangle.rs
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+++ b/src/test/ui/nll/drop-may-dangle.rs
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+// 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) { }
+}