4 files changed, 145 insertions, 0 deletions
diff --git a/tests/ui/drop/dropck-eyepatch-manuallydrop.rs b/tests/ui/drop/dropck-eyepatch-manuallydrop.rs
new file mode 100644
index 000000000..ff100cd94
--- /dev/null
+++ b/tests/ui/drop/dropck-eyepatch-manuallydrop.rs
@@ -0,0 +1,22 @@
+// check-pass
+//! This test checks that dropck knows that ManuallyDrop does not drop its field.
+#![feature(dropck_eyepatch)]
+
+use std::mem::ManuallyDrop;
+
+struct S<T>(ManuallyDrop<T>);
+
+unsafe impl<#[may_dangle] T> Drop for S<T> {
+    fn drop(&mut self) {}
+}
+
+struct NonTrivialDrop<'a>(&'a str);
+impl<'a> Drop for NonTrivialDrop<'a> {
+    fn drop(&mut self) {}
+}
+
+fn main() {
+    let s = String::from("string");
+    let _t = S(ManuallyDrop::new(NonTrivialDrop(&s)));
+    drop(s);
+}
diff --git a/tests/ui/drop/issue-110682.rs b/tests/ui/drop/issue-110682.rs
new file mode 100644
index 000000000..35f9c7e8d
--- /dev/null
+++ b/tests/ui/drop/issue-110682.rs
@@ -0,0 +1,92 @@
+// build-pass
+// compile-flags: -Zmir-opt-level=3
+
+use std::fmt::Debug;
+use std::mem::ManuallyDrop;
+use std::ptr;
+
+pub trait BitRegister {}
+
+macro_rules! register {
+    ($($t:ty),+ $(,)?) => { $(
+        impl BitRegister for $t {
+        }
+    )* };
+}
+
+register!(u8, u16, u32);
+
+pub trait BitStore: Sized + Debug {
+    /// The register type that the implementor describes.
+    type Mem: BitRegister + Into<Self>;
+}
+
+macro_rules! store {
+    ($($t:ty),+ $(,)?) => { $(
+        impl BitStore for $t {
+            type Mem = Self;
+        }
+    )+ };
+}
+
+store!(u8, u16, u32,);
+
+#[repr(C)]
+pub struct BitVec<T>
+where
+    T: BitStore,
+{
+    /// Region pointer describing the live portion of the owned buffer.
+    pointer: ptr::NonNull<T>,
+    /// Allocated capacity, in elements `T`, of the owned buffer.
+    capacity: usize,
+}
+
+impl<T> BitVec<T>
+where
+    T: BitStore,
+{
+    pub fn new() -> Self {
+        let pointer = ptr::NonNull::<T>::new(ptr::null_mut()).unwrap();
+
+        BitVec { pointer, capacity: 10 }
+    }
+
+    pub fn clear(&mut self) {
+        unsafe {
+            self.set_len(0);
+        }
+    }
+
+    #[inline]
+    pub unsafe fn set_len(&mut self, new_len: usize) {}
+
+    fn with_vec<F, R>(&mut self, func: F) -> R
+    where
+        F: FnOnce(&mut ManuallyDrop<Vec<T::Mem>>) -> R,
+    {
+        let cap = self.capacity;
+        let elts = 10;
+        let mut vec = ManuallyDrop::new(unsafe { Vec::from_raw_parts(ptr::null_mut(), elts, cap) });
+        let out = func(&mut vec);
+
+        out
+    }
+}
+
+impl<T> Drop for BitVec<T>
+where
+    T: BitStore,
+{
+    #[inline]
+    fn drop(&mut self) {
+        //  The buffer elements do not have destructors.
+        self.clear();
+        //  Run the `Vec` destructor to deällocate the buffer.
+        self.with_vec(|vec| unsafe { ManuallyDrop::drop(vec) });
+    }
+}
+
+fn main() {
+    let bitvec = BitVec::<u32>::new();
+}
diff --git a/tests/ui/drop/issue-979.rs b/tests/ui/drop/issue-979.rs
new file mode 100644
index 000000000..57a99b325
--- /dev/null
+++ b/tests/ui/drop/issue-979.rs
@@ -0,0 +1,29 @@
+// run-pass
+#![allow(non_camel_case_types)]
+
+use std::cell::Cell;
+
+struct r<'a> {
+    b: &'a Cell<isize>,
+}
+
+impl<'a> Drop for r<'a> {
+    fn drop(&mut self) {
+        self.b.set(self.b.get() + 1);
+    }
+}
+
+fn r(b: &Cell<isize>) -> r {
+    r {
+        b: b
+    }
+}
+
+pub fn main() {
+    let b = &Cell::new(0);
+    {
+        let _p = Some(r(b));
+    }
+
+    assert_eq!(b.get(), 1);
+}
diff --git a/tests/ui/drop/repeat-drop.rs b/tests/ui/drop/repeat-drop.rs
index 8fd46ecaf..0afb4bb11 100644
--- a/tests/ui/drop/repeat-drop.rs
+++ b/tests/ui/drop/repeat-drop.rs
@@ -1,6 +1,8 @@
 // run-pass
 // needs-unwind
 
+#![allow(dropping_references, dropping_copy_types)]
+
 static mut CHECK: usize = 0;
 
 struct DropChecker(usize);