Storage Pools and alloca

["Frank J. Lhota" <NOSPAM.lhota.adarose@verizon.net>]

C / C++ sometimes cut down on the hassles of memory management by using the
"alloca" function. The "alloca" function, which is frequently implicit,
allocates storage from the stack. Since memory allocated by "alloca" is on
the stack, it is reclaimed automatically as soon as the function that
allocated this memory returns.

AFAIK, the "alloca" functionality could be added to Ada using the storage
pool facility. One could derive a type from
System.Storage_Pools.Root_Storage_Pool and write the required subprograms
for this type as follows:

    - The Allocate procedure would allocate memory from the stack, sort of
like the C "alloca" function;
    - The Deallocate procedure should do nothing; and
    - The Storage_Size should return the amount of space left on the stack.

Of course, this is highly platform dependant, and would often require
machine code insertions.

Questions:

    1) Does any Ada compiler provide this type of storage pool?
    2) If this type of storage pool was available, would you find it useful?
    3) Would an "alloca" storage pool be a worthwhile addition to Ada 0x?