1 files changed, 31 insertions, 0 deletions
diff --git a/tests/ui/unboxed-closures/unboxed-closures-move-mutable.rs b/tests/ui/unboxed-closures/unboxed-closures-move-mutable.rs
new file mode 100644
index 000000000..470904fd3
--- /dev/null
+++ b/tests/ui/unboxed-closures/unboxed-closures-move-mutable.rs
@@ -0,0 +1,31 @@
+// run-pass
+// pretty-expanded FIXME #23616
+
+#![deny(unused_mut)]
+#![allow(unused_must_use)]
+
+// Test that mutating a mutable upvar in a capture-by-value unboxed
+// closure does not ice (issue #18238) and marks the upvar as used
+// mutably so we do not get a spurious warning about it not needing to
+// be declared mutable (issue #18336 and #18769)
+
+fn set(x: &mut usize) { *x = 42; }
+
+fn main() {
+    {
+        let mut x = 0_usize;
+        move || x += 1; //~ WARN unused variable: `x`
+    }
+    {
+        let mut x = 0_usize;
+        move || x += 1; //~ WARN unused variable: `x`
+    }
+    {
+        let mut x = 0_usize;
+        move || set(&mut x);
+    }
+    {
+        let mut x = 0_usize;
+        move || set(&mut x);
+    }
+}