Rust: Merge of unusedvar and unreachable work.

Author: geoffw0

rust/ql/test/query-tests/unusedentities/UnreachableCode.expected

@@ -1,3 +1,4 @@
+| main.rs:114:3:114:29 | ExprStmt | This code is never reached. |
 | unreachable.rs:32:3:32:17 | ExprStmt | This code is never reached. |
 | unreachable.rs:39:3:39:17 | ExprStmt | This code is never reached. |
 | unreachable.rs:48:2:48:16 | ExprStmt | This code is never reached. |

rust/ql/test/query-tests/unusedentities/main.rs

@@ -111,7 +111,7 @@ fn arrays() {
 	println!("lets use {:?}", js);
 
 	for k in ks {
-		println!("lets use {}", k);
+		println!("lets use {}", k); // [unreachable FALSE POSITIVE]
 	}
 }
 
@@ -142,11 +142,17 @@ fn parameters(
 	return x;
 }
 
+// --- main ---
+
 fn main() {
 	locals_1();
 	locals_2();
 	structs();
 	arrays();
 	statics();
 	println!("lets use result {}", parameters(1, 2, 3));
+	unreachable_if();
+	unreachable_panic();
+	unreachable_match();
+	unreachable_loop();
 }