Re: Ada / Motif Binding Question

[Ted Dennison <dennison@telepath.com>]

Tony Yu wrote:

>     procedure Exit_Option (W : X_Support.Xt.Widget;
> 
>         Client_Data : X_Support.Xt.Xt_Pointer;
> 
>         Call_Data : X_Support.Xt.Xt_Pointer) is
> 
>         My_String : String (1 .. 625) := (others => ' ');
> 
>         procedure C_Exit (Status : Integer);
> 
>         pragma Import (C, C_Exit, External_Name => "exit");
> 
>         begin
> 
>             C_Exit (0);
> 
>         end Exit_Option;

 >

> After invoking the callback, I get the following error:
> 
>  -> ** MAIN PROGRAM ABANDONED -- EXCEPTION "STORAGE_ERROR" RAISED

You didn't say what Motif bindings you are using. There's no one 
standard set that comes with every compiler (which makes sense, as Win32 
compilers don't typically have Motif around to bind to).

One possibility I see is that "Exit_Option" does not have a "pragma 
Convention (C, ...)" on it. Ada procedures and C functions usually have 
different calling sequences, and Motif expects to be "talking C" to its 
callbacks.

However, some bindings take care of this for you, which is why it 
matters what bindings you have.


Another possibility is that C_Exit() (whatever that is) is causing you 
grief. You could try changing that line to "null;" to see if the crash 
goes away.