1 files changed, 34 insertions, 0 deletions

diff --git a/src/test/ui/issues/issue-39827.rs b/src/test/ui/issues/issue-39827.rs
new file mode 100644
index 000000000..782c668c8
--- /dev/null
+++ b/src/test/ui/issues/issue-39827.rs
@@ -0,0 +1,34 @@
+// run-pass
+#![feature(core_intrinsics)]
+
+use std::intrinsics::{ volatile_copy_memory, volatile_store, volatile_load,
+                       volatile_copy_nonoverlapping_memory,
+                       volatile_set_memory };
+
+//
+// This test ensures that volatile intrinsics can be specialised with
+// zero-sized types and, in case of copy/set functions, can accept
+// number of elements equal to zero.
+//
+fn main () {
+    let mut dst_pair = (1, 2);
+    let src_pair = (3, 4);
+    let mut dst_empty = ();
+    let src_empty = ();
+
+    const COUNT_0: usize = 0;
+    const COUNT_100: usize = 100;
+
+    unsafe {
+        volatile_copy_memory(&mut dst_pair, &dst_pair, COUNT_0);
+        volatile_copy_nonoverlapping_memory(&mut dst_pair, &src_pair, 0);
+        volatile_copy_memory(&mut dst_empty, &dst_empty, 100);
+        volatile_copy_nonoverlapping_memory(&mut dst_empty, &src_empty,
+                                            COUNT_100);
+        volatile_set_memory(&mut dst_empty, 0, COUNT_100);
+        volatile_set_memory(&mut dst_pair, 0, COUNT_0);
+        volatile_store(&mut dst_empty, ());
+        volatile_store(&mut dst_empty, src_empty);
+        volatile_load(&src_empty);
+    }
+}