Re: Compiling C and Ada sources together

[Simon Wright <simon@pushface.org>]

<lange92@2067.resnet.uni.edu> writes:

>   I've been working on a project where we compile C source files and
> Ada sources together to produce a single binary. Most of it is
> automated at this point, but for debugging reasons I need to know
> how to do it by hand.  A long time ago, I saw an article (I thought
> it was on www.adahome.com) about how to link together sources from
> each language, particularly in the case where the C program makes
> calls to the ada source (the main program is in C) so the
> Interfaces.C functionality is not used.

If you're going to call Ada from C, you need to use pragma Export --
and it's best to be simple at this interface! (just simple types).

  function Foo (X : Integer) return Boolean;
  pragma Export (C, Foo, "package_foo");

(I'm not sure whether all compilers are clever enough to set all
Interfaces.C.int'Size bits of the Boolean result before returning it!)