@nogc and lazy arguments

[Dicebot via Digitalmars-d-learn]

On Sunday, 27 April 2014 at 13:09:39 UTC, bearophile wrote:
> Lazy arguments in general allocate, but who is to blame for the 
> allocation?
> Isn't the allocation at the calling point?
>
> This code:
>
>
> void foo(lazy int x) @nogc {
>     auto r = x(); // Error
> }
> void main() {
>     foo(1);
> }
>
>
> Gives:
>
> test.d(2,15): Error: @nogc function 'test.foo' cannot call 
> non- at nogc delegate 'x'
>
> Is it right to refuse the @nogc annotation on foo()? I think 
> here foo should be allowed to be @nogc, while the main() can't 
> be @nogc. What do you think?
>
> Bye,
> bearophile

It happens because attribute inference does not work properly on 
generated delegated for lazy argument. I think it is a bug

"lazy int x" is effectively same as "int delegate() x" and @nogc 
states that you can only call other @nogc functions and delegates 
from something annotated as @nogc.