Re: Ada95 & C++ Interfacing

[dewar@cs.nyu.edu (Robert Dewar)]

Nigel asks

Is the C++ interface part of the language ?

  No, it could not possibly be. Ada 95 is an ISO standard language, and an
  ISO standard cannot reference non-standardized languages that are in a
  state of flux!

  However, GNAT does implement an interface to C++ that can be tailored
  to multiple C++ compilers. So far we have interfaced to g++ (the gcc
  version of C++) and to SGI Delta C++.

Will all Ada95 compilers be required to support this interface?

  Certainly not, because there is nothing in the language. However, the ARA,
  which is an industry consortium is developing guidelines for such interfaces
  that we hope all Ada 95 compilers will follow. The work in developing the
  ACE (Ada Common Environment), which defines common bindings, interfaces,
  pragas, attributes etc. is an open effort in which all the major Ada vendors
  are involved. The intention is that we try to encourage as much commonality
  as possible, but certainly there is no requirement. In fact Ada 95 compilers
  are not required to support anything. You can take a Pascal compiler and
  call it an Ada 95 compiler if you like -- there are no Ada police around
  to come and stop you :-)

  Now no one requires that you have NIST validate the compiler, but if you
  do, then of course you must pass the validation suite, but this suite
  certainly will not test C++ interfaces, since it refers only to the standard.

Initially I will be developing ideas using gcc & gnat.
Eventually I will probably develop the system using Rational Apex.

  Note that this is not necessarily an either/or, some of our big customers
  are experimenting with developing using Rational Apex and then using GNAT
  for the actual final compilation and delivery. Apex with its RCI (remote
  compiler interface) is well set up for such usage, and indeed Rational has
  developed an RCI interface specifically for GNAT. You will have to wait for
  the full Ada 95 version of APEX to be available, but when it is, this will
  definitely be one possible approach.

Does gdb support debugging of mixed language systems ?

  Definitely yes. gdb knows which language the current unit is written in,
  and adapts its syntax and behavior to match the current language.