• Mike (7/7) Jun 25 2005 1. Are structs allocated on the stack? I'm assuming so, since otherwise ...
• Chris Sauls (9/13) Jun 25 2005 Yes. Yes they are. And I agree that it ought to be explicitly stated i...
• Mike (7/9) Jun 25 2005 If there was a special rule, I'd expect a compiler error when attempting...
• David Medlock (5/10) Jun 27 2005 They dont have to be. just use

Mike <Mike_member pathlink.com> writes:

1. Are structs allocated on the stack? I'm assuming so, since otherwise you'd
have to pin them before passing their addresses to external APIs in case a
compacting GC collection moved them, but AFAICS the spec doesn't actually come
out and say so.

2. Why don't protection attributes ('private' etc) work with structs? The
compiler doesn't complain about them, but doesn't stop outside code (in another
module) modifying private members directly.

Chris Sauls <ibisbasenji gmail.com> writes:

Mike wrote:
 1. Are structs allocated on the stack?

Yes.  Yes they are.  And I agree that it ought to be explicitly stated in the
docs.  I 
could've sworn that it was said somewhere, but I couldn't find it just now. 
Walter? 
Something to update... :)

 2. Why don't protection attributes ('private' etc) work with structs? The
 compiler doesn't complain about them, but doesn't stop outside code (in another
 module) modifying private members directly.

I thought they did... but I just tested it, and sure enough, they don't.  Which
is strange 
since the D paradigm is that all protection attributes (except 'protected') are
really on 
the /module/ level, not the aggragate level.  If there is a special rule for
structs, it 
also should be said somewhere...

-- Chris Sauls

Mike <Mike_member pathlink.com> writes:

Chris, thanks for the reply.

In article <d9kcgm$2vlf$1 digitaldaemon.com>, Chris Sauls says...
If there is a special rule for structs, it 
also should be said somewhere...

If there was a special rule, I'd expect a compiler error when attempting to use
a protection  attribute in a struct. This feels like an oversight.

And I'd _much_ prefer protection to be implemented for structs. Just because an
aggregate is lightweight doesn't mean it doesn't have invariants that need
protection.

David Medlock <noone nowhere.com> writes:

Mike wrote:
 1. Are structs allocated on the stack? I'm assuming so, since otherwise you'd
 have to pin them before passing their addresses to external APIs in case a
 compacting GC collection moved them, but AFAICS the spec doesn't actually come
 out and say so.
 

They dont have to be. just use

struct MyStruct  { int a = 1; }
MyStruct* ptr = new MyStruct();
MyStruct* many = new MyStruct[100];