add test for issue-4355

Author: sasurau4

tests/source/issue-4355.rs

@@ -0,0 +1,13 @@
+impl Drop for LockGuard {
+    fn drop(&mut self) {
+        LockMap::unlock(&self.0.0, &self.0.1);
+    }
+}
+
+fn main() {
+    let _ = ((1,),).0.0;
+
+    let t1 = (1u8, 2u8);
+    let mut t2 = (t1, 3u8);
+    t2.1 = t2.0.1;
+}

tests/target/issue-4355.rs

@@ -0,0 +1,13 @@
+impl Drop for LockGuard {
+    fn drop(&mut self) {
+        LockMap::unlock(&self.0 .0, &self.0 .1);
+    }
+}
+
+fn main() {
+    let _ = ((1,),).0 .0;
+
+    let t1 = (1u8, 2u8);
+    let mut t2 = (t1, 3u8);
+    t2.1 = t2.0 .1;
+}