Re: library files

["Marc A. Criley" <mcNOSPAM@mckae.com>]

"Harry Overs" <hovers@dera.gov.uk> wrote:

> we've got some legacy Ada source code which we want to compile into a
> library which will be accessed using a MS VC++ application.  Although
we've
> managed to compile the ada code and turn the .o files into a library when
it
> comes to linking the C++ program we get thousands of errors which seem to
> relate to system calls within the library (i.e. put method).
> Do we need to do anything 'special' whilst creating the library or the
> object files? at present we just use (from the command line):
>
> ar r myLib.lib *.o

A bit more info is needed to answer this:

What Ada compiler is being used?

Have the Ada subprograms that are going to be called from C++ been
designated with "pragma Export" if Ada 95, or if Ada 83, have the vendor's
directions for invoking Ada from a non-Ada program been followed?

Other libraries from the vendor's Ada runtime library may also need to be
linked into the executable. Have those been identified?

Is it assured that this Ada compiler's runtime library is interoperable with
VC++? Not all are. (And if not, all is not lost--you can put a "messaging
wrapper" around the Ada code and gin up a message-based communication
protocol to invoke the Ada portion and pass data back and forth. Hurts
performance, but the import of that depends on your application's purpose.)

Marc A. Criley
McKae Technologies
www.mckae.com