Add a test

src/test/run-pass/no-core-2.rs

@@ -0,0 +1,18 @@
+#![allow(dead_code, unused_imports)]
+#![feature(no_core)]
+#![no_core]
+// edition:2018
+
+extern crate std;
+extern crate core;
+use core::{prelude::v1::*, *};
+
+fn foo() {
+    for _ in &[()] {}
+}
+
+fn bar() -> Option<()> {
+    None?
+}
+
+fn main() {}