Merging upstream version 1.68.2+dfsg1.

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

1 files changed, 37 insertions, 0 deletions

diff --git a/tests/ui/span/issue28498-reject-ex1.rs b/tests/ui/span/issue28498-reject-ex1.rs
new file mode 100644
index 000000000..4d1b41255
--- /dev/null
+++ b/tests/ui/span/issue28498-reject-ex1.rs
@@ -0,0 +1,37 @@
+// Example taken from RFC 1238 text
+
+// https://github.com/rust-lang/rfcs/blob/master/text/1238-nonparametric-dropck.md
+//     #examples-of-code-that-will-start-to-be-rejected
+
+// Compare against test/run-pass/issue28498-must-work-ex2.rs
+
+use std::cell::Cell;
+
+struct Concrete<'a>(u32, Cell<Option<&'a Concrete<'a>>>);
+
+struct Foo<T> { data: Vec<T> }
+
+fn potentially_specialized_wrt_t<T>(t: &T) {
+    // Hypothetical code that does one thing for generic T and then is
+    // specialized for T == Concrete (and the specialized form can
+    // then access a reference held in concrete tuple).
+    //
+    // (We don't have specialization yet, but we want to allow for it
+    // in the future.)
+}
+
+impl<T> Drop for Foo<T> {
+    fn drop(&mut self) {
+        potentially_specialized_wrt_t(&self.data[0])
+    }
+}
+
+fn main() {
+    let mut foo = Foo {  data: Vec::new() };
+    foo.data.push(Concrete(0, Cell::new(None)));
+    foo.data.push(Concrete(0, Cell::new(None)));
+
+    foo.data[0].1.set(Some(&foo.data[1]));
+    //~^ ERROR borrow may still be in use when destructor runs
+    foo.data[1].1.set(Some(&foo.data[0]));
+}