!standard D.7(8)                                09-11-03  AI05-0190-1/01
!class amendment 09-11-03
!status work item 09-11-03
!status received 09-11-03
!priority Low
!difficulty Easy
!subject Restriction No_Allocation_from_Default_Pools

!summary

Provide a restriction that disallows use of allocators for types
that use the default storage pool.

!problem

It is common to have a coding convention that only user-defined storage 
pools be used for all access types.  This restriction allows the 
implementation to enforce this coding convention.

!proposal

(see summary)

!wording

Add after D.7(8):

  No_Allocation_From_Default_Pools
  
     Every allocator shall be:
     
       * of a named access type with a Storage_Pool attribute that
         denotes a user-defined object;

       * of an anonymous access type, used to define the value of an
         access parameter or access discriminant; or

       * of an anonymous access type, used in a context where the storage
         pool is defined to be the same as that of a permitted allocator.

!discussion

We have allowed anonymous allocators so long as they can be allocated on
the stack, or in a storage pool that is user-defined.  We have not
permitted an allocator for an access type with a Storage_Size attribute,
because those still involve heap allocation and potentially unchecked
deallocation using implementation-specific algorithms.

!example

!ACATS test

An ACATS B test is needed.

!appendix

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