Postblit isn't called on rvalue return

[Sebastian Graf]

On Wednesday, 24 April 2013 at 20:53:11 UTC, Ali Çehreli wrote:
>
> First, as the local 's' in makeS() is local, it cannot be 
> returned by ref. So, the 'auto ref' return type of makeS() 
> becomes by-value.
>
> However, rvalues are never copied in D. The compiler 
> automatically moves the bits of the rvalue to the left-hand 
> side object, and to be correct, it also elides the destructor 
> execution on the rvalue. (Note that this is not the RVO and 
> NRVO optimization that C++ "allows". This is a language feature 
> in D.)
>
> For that feature to be available at all, struct objects must 
> not have references to themselves; D explicitly makes it 
> illegal.
>
> So, unfortunately your S is not a valid type in D because of 
> the following line (.ptr is added by me):
>
>     s.b = s.buf.ptr;
>
> Ali

Thanks, this explains a lot. I was interfacing with a C library 
when tracing back an error to this. I eagerly submitted a Bug 
report http://d.puremagic.com/issues/show_bug.cgi?id=9985. Seems 
to me that dmd doesn't do NRVO (?), see the issue.