How does the compiler avoid creating a closure here?

[Walter Bright via Digitalmars-d]

On 6/2/2015 11:05 PM, Andrei Alexandrescu wrote:
> Consider http://dpaste.dzfl.pl/fork/ae75176d7d3f.
>
> It's a bit roundabout but in brief it instantiates a template with a nested
> function. The nested function, in turn, uses a parameter in its environment. By
> the canon, that function needs to create a closure with dynamically-allocated
> environment.
>
> To my surprise, however, the generated code uses no closure (disassembly at
> http://goo.gl/ti23W0) yet works correctly.
>
> How come? Can anyone explain to me where x (used by the nested function) is stored?

It doesn't avoid creating a closure. The dpaste compiler is not showing the call 
to __d_allocmemory because it is incorrectly resolving it to another symbol.

(A closure can be detected by the presence of a call to __d_allocmemory.)