Storage Pool

Storage Pool

[ANH_VO]

Is it correct to assume that Size_In_Storage_Element mod Alignment = 0 for both
subprograms Allocate and Deallocate for any type derived from Root_Storage_Pool
as shown below

   procedure Allocate (
      Pool            : in out General_Pool;
      Storage_Address :    out System.Address;
      Size_In_Storage_Elements : in System.Storage_Elements.Storage_Count;
      Alignment       : in System.Storage_Elements.Storage_Count);

   procedure Deallocate (
      Pool            : in out General_Pool;
      Storage_Address : in     System.Address;
      Size_In_Storage_Elements : in System.Storage_Elements.Storage_Count;
      Alignment       : in System.Storage_Elements.Storage_Count);

   where type General_Pool (Size : System.Storage_Elements.Storage_Count;
                            User : access String ) is new
                       System.Storage_Pools.Root_Storage_Pool with private;
   ...

   or is it compiler dependent?
   
   Thanks.

   Anh Vo

Re: Storage Pool

[Robert A Duff]

ANH_VO@udlp.com writes:

> Is it correct to assume that Size_In_Storage_Element mod Alignment = 0 for both
> subprograms Allocate and Deallocate for any type derived from Root_Storage_Pool
> as shown below

No.  But you can write a storage pool that requires that, and only use
it for types that obey that rule.

I have written storage pools that assume Alignment = 4 (and
pragma-assert so).

- Bob

Re: Storage Pool

[Randy Brukardt]

ANH_VO@udlp.com wrote in message ...
>Is it correct to assume that Size_In_Storage_Element mod Alignment = 0
for both
>subprograms Allocate and Deallocate for any type derived from
Root_Storage_Pool
>as shown below


I don't think you should assume anything not required by the reference
manual. And certainly this is not required by the reference manual.
Unless you want your code to work only with a particular implementation.


         Randy.


GNAT /= Ada 95