---
void foo(alias f)() {
    f();
}

void bar() {
        foo!({})();
}

void main() {
        bar();
}
---

dmd -inline -c m1.d
m1.d(1): Error: function m1.bar.foo!(delegate void()
{
}
).foo is a nested function and cannot be accessed from main

Pretty similar to bug 5499 but not the same as the failures are so different.