Re: Odd Behaviour

[Mark Wilson <markwilson@wilsonnet.technology>]

On Tuesday, January 18, 2022 at 11:48:23 AM UTC, Jeffrey R.Carter wrote:
> On 2022-01-18 12:05, Mark Wilson wrote: 
> >
> > then an error is raised: 'warning: Valued_Procedure has no effect for convention Ada [enabled by default]'
> The GNAT RM says of pragma Import_Valued_Procedure 
> 
> "Note that it is important to use this pragma in conjunction with a separate 
> pragma Import that specifies the desired convention, since otherwise the default 
> convention is Ada, which is almost certainly not what is required." 
> 
> What happens if you replace the import aspects with pragma Import?
> -- 
> Jeff Carter 
> "Monsieur Arthur King, who has the brain of a duck, you know." 
> Monty Python & the Holy Grail 
> 09

Tried pragma Import, and even pragma Convention, so, for instance,

   procedure SQLAllocHandle
     (Result          : out    SQLRETURN;
      HandleType      : in     SQL_HANDLE_TYPE;
      InputHandle     : in     SQLHANDLE;
      OutputHandlePtr : in out SQLHANDLE)
     with
       Pre =>   (Handletype = SQL_Handle_Env);

   pragma Import (C, SQLAllocHandle, "SQLAllocHandle");
   pragma Import_Valued_Procedure (SQLAllocHandle);

Fails with the same warning. Take the 'pre' out and it works fine.