void foo()(auto ref int x) {} alias foo!() bar; $ dmd test.d test.d(1): Error: auto can only be used for template function parameters test.d(2): Error: template instance test.foo!() error instantiating You get a similar error if you try to take the address of foo!()
*** Issue 14657 has been marked as a duplicate of this issue. ***
*** This issue has been marked as a duplicate of issue 8204 ***