> is having Address be an integer useful any more? Nowadays it should be > possible to declare Address to be an access type with no associated storage > pool. Even nicer might be to have it be turned into void* when lowering to > GCC types. After all, Address is really used much like void*; see how GNAT > declares malloc for example. Both of these possibilities would probably > play better with GCC's middle end type system, which considers integers to > be different to pointers.
The polymorphism pointer/address indeed proves to be problematic in certain circumstances (e.g. it breaks on m68k, see PR ada/48835). My understanding is that using pointers in Ada is heavyweight, hence the choice of an integer for System.Address; and I'm reluctant to enter the type morphing business in gigi. But we could investigate changing System.Memory to use an access type instead of System.Address. It's a compiler unit so the impact should be limited, and at least this would solve the m68k problem. -- Eric Botcazou
