The heap control switches –
determine whether dynamic allocation uses 32-bit or 64-bit memory.
They only affect compiler-generated allocations via
explicit calls to
malloc and related functions from the C
run-time library are unaffected.
Allocate memory on 32-bit heap
Allocate memory on 64-bit heap. This is the default
unless explicitly overridden by a
'Size clause on the access type.
These switches are only effective on VMS platforms.