A valid function with no return type?

[Meta]

On Thursday, 24 September 2020 at 21:39:18 UTC, Stefan Koch wrote:
> On Thursday, 24 September 2020 at 21:32:20 UTC, Meta wrote:
>> On Thursday, 24 September 2020 at 21:26:30 UTC, Max Haughton 
>> wrote:
>>> https://issues.dlang.org/show_bug.cgi?id=12638
>>>
>>> https://run.dlang.io/is/jkEIiI
>>>
>>> ref foo() {}
>>>
>>> void main()
>>> {
>>>     import std.traits;
>>>     pragma(msg, ReturnType!foo);
>>>     foo();
>>> }
>>>
>>> Assuming this is supposed to be allowed by the standard, 
>>> replacing void with ref (i.e. ref main { ) does not compile 
>>> which suggests something isn't right.
>>
>> Anything other than `void main()`, `void main(string[] args)`, 
>> `int main()`, `int main(string[] args)` will cause the 
>> compiler report a compile error. It's probably special-cased 
>> in the compiler somewhere.
>
> Actually that's wrong.
> The compiler will happily accept any number of qualifiers you 
> stick on your main.

Qualifiers yes but not return types/storage classes, isn't it? 
`ref` here is not a qualifier on the function; it's specifying 
the storage class for the return type.