add regression test for rust-lang#80074

Author: TaKO8Ki

src/test/ui/extern/auxiliary/issue-80074-macro.rs

@@ -0,0 +1,4 @@
+// edition:2018
+
+macro_rules! foo_ { () => {}; }
+use foo_ as foo;

src/test/ui/extern/issue-80074.rs

@@ -0,0 +1,10 @@
+// edition:2018
+// build-pass
+// aux-crate:issue_80074=issue-80074-macro.rs
+
+#[macro_use]
+extern crate issue_80074;
+
+fn main() {
+    foo!();
+}