Reenable MIR test

Fixes #30674

Author: nagisa

src/test/run-pass/mir_trans_calls.rs

@@ -58,16 +58,11 @@ fn test5(x: &Bar, a: isize) -> isize {
     x.extension_method(a)
 }
 
-// FIXME #30661: Although this function has the #[rustc_mir] attribute it never
-//               was translated via the MIR implementation because attributes
-//               where not passed along to trans::base::trans_fn() for generic
-//               functions.
-//               Uncomment this test once the thing it tests is fixed.
-// #[rustc_mir]
-// fn test6<T: Bar>(x: &T, a: isize) -> isize {
-//     // Test calling extension method on generic callee
-//     x.extension_method(a)
-// }
+#[rustc_mir]
+fn test6<T: Bar>(x: &T, a: isize) -> isize {
+    // Test calling extension method on generic callee
+    x.extension_method(a)
+}
 
 trait One<T = Self> {
     fn one() -> T;
@@ -119,8 +114,7 @@ fn main() {
     assert_eq!(test3(&Foo, 42), 42);
     assert_eq!(test4(&Foo, 970), 970);
     assert_eq!(test5(&Foo, 8576), 8576);
-    // see definition of test6() above
-    // assert_eq!(test6(&Foo, 12367), 12367);
+    assert_eq!(test6(&Foo, 12367), 12367);
     assert_eq!(test7(), 1);
     assert_eq!(test8(), 2);