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digitalmars.D.learn - how to set struct alignof?

reply "Andrew Fedoniouk" <news terrainformatica.com> writes:
As stated in D documetation (http://www.digitalmars.com/d/struct.html):

a.. [structure] "alignment can be explicitly specified"

The question is : how?

What notation I should use to define alignof for let's say
struct A
{
   ushort B;
}

Thanks.
Mar 21 2005
next sibling parent reply "Regan Heath" <regan netwin.co.nz> writes:
On Mon, 21 Mar 2005 16:25:33 -0800, Andrew Fedoniouk  
<news terrainformatica.com> wrote:

 As stated in D documetation (http://www.digitalmars.com/d/struct.html):

 a.. [structure] "alignment can be explicitly specified"

 The question is : how?



See:
http://www.digitalmars.com/d/attribute.html#align

Regan
Mar 21 2005
parent reply Derek Parnell <derek psych.ward> writes:
On Tue, 22 Mar 2005 12:33:48 +1200, Regan Heath wrote:


 On Mon, 21 Mar 2005 16:25:33 -0800, Andrew Fedoniouk  
 <news terrainformatica.com> wrote:

 As stated in D documetation (http://www.digitalmars.com/d/struct.html):

 a.. [structure] "alignment can be explicitly specified"

 The question is : how?



 See:
 http://www.digitalmars.com/d/attribute.html#align
 
 Regan



The 'align(x)' attribute is used to tell DMD how to align structures and
not the structure members.  To align the members inside a struct you need
to set the struct alignment to 1, and then provide explicit fillers for
gaps in the RAM mapping.

  align(1) struct MyStruct
  { 
     byte A;
     byte[3] filler1;
     byte B;
     byte filler2;
     short C;
  }


-- 
Derek
Melbourne, Australia
22/03/2005 11:38:37 AM
Mar 21 2005
parent Derek Parnell <derek psych.ward> writes:
On Tue, 22 Mar 2005 11:42:11 +1100, Derek Parnell wrote:


 On Tue, 22 Mar 2005 12:33:48 +1200, Regan Heath wrote:
 

 On Mon, 21 Mar 2005 16:25:33 -0800, Andrew Fedoniouk  
 <news terrainformatica.com> wrote:

 As stated in D documetation (http://www.digitalmars.com/d/struct.html):

 a.. [structure] "alignment can be explicitly specified"

 The question is : how?



 See:
 http://www.digitalmars.com/d/attribute.html#align
 
 Regan



 The 'align(x)' attribute is used to tell DMD how to align structures and
 not the structure members.  To align the members inside a struct you need
 to set the struct alignment to 1, and then provide explicit fillers for
 gaps in the RAM mapping.
 
   align(1) struct MyStruct
   { 
      byte A;
      byte[3] filler1;
      byte B;
      byte filler2;
      short C;
   }



Ummmm... should this compile ok?

import std.stdio;
align(1) struct MyStruct
{
   byte A;
   byte[3] filler1;
   byte B;
   byte filler2;
   short C;
}

void main()
{
    MyStruct s;

    writefln("%d %d %d",
            s.A.offsetof,
            s.B.offsetof,
            s.C.offsetof);
}

-- 
Derek
Melbourne, Australia
22/03/2005 11:42:38 AM
Mar 21 2005
prev sibling parent "Andrew Fedoniouk" <news terrainformatica.com> writes:
Thanks a lot, guys.
Mar 21 2005