Fix test.

Author: cjgillot

src/test/run-make-fulldeps/issue-19371/foo.rs

@@ -66,6 +66,11 @@ fn compile(code: String, output: PathBuf, sysroot: PathBuf) {
 
     interface::run_compiler(config, |compiler| {
         // This runs all the passes prior to linking, too.
-        compiler.link().ok();
+        let linker = compiler.enter(|queries| {
+            queries.linker()
+        });
+        if let Ok(linker) = linker {
+            linker.link();
+        }
     });
 }