Re: StdCall and pragma Import_Function

[Adam Beneschan <adam@irvine.com>]

On Aug 19, 9:51 am, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:
> On Fri, 19 Aug 2011 09:24:33 -0700 (PDT), Felix Krause wrote:
> >    pragma Import (StdCall, C_Function, "cFunc");
> >    pragma Import_Function (Internal => C_Function, External => "cFunc", Mechanism => (Param => Value));
> > end P;
>
> Stdcall is the calling convention used by Windows API.  If you want to call
> a C function then most likely it rather should be C, i.e.
>
>    pragma Import (C, ...);

The OP did say that the symbol name _cFunc@8 exists in the library,
which indicates that using StdCall appears to be correct, just that
GNAT is using the wrong size for the symbol.

Offhand, this looks like a bug, but there may be some other legitimate
reason why GNAT isn't getting the size right, and I'm not familiar
enough with GNAT-specific pragmas to be of any more help.  Out of
curiosity, Felix, what happens if you add a 62-bit "filler" field to
Bit_Vector, with 2..63 in the representation clause?  Does that make
things work?

                                   -- Adam