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From: Rod Kay <rodakay5@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Using pointers with inline assembly in Ada
Date: Fri, 10 Jun 2022 15:24:35 +1000
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On 10/6/22 07:30, NiGHTS wrote:
> declare
>           type ff is array (0 .. 10) of Unsigned_32;
>           pragma Pack(ff);
>           Flags : aliased ff := (others => 0);
>           Flag_Address : System.Address := Flags'Address;
> begin
>          Asm (   "movl %0, %%eax" &
>                  "movl $1, (%%eax)" ,
>                  Inputs   => System.Address'Asm_Input ("g", Flag_Address),
>                  Clobber  => "eax",
>                  Volatile => true
>          );
>          Put_Line ("Output:" & Flags(0)'Img);
> end;
> 

    If you are on a 64 bit machine, then I expect 'pragma Pack' might be 
the problem, as 2 consecutive array elements will fir into a single address.


    Also, possibly use ...

    Flag_Address : System.Address := Flags (Flags'First)'Address;


Regards.