Re: Forcing GNAT to use 32-bit load/store instructions on ARM?

["Randy Brukardt" <randy@rrsoftware.com>]

"Simon Clubley" <clubley@remove_me.eisner.decus.org-Earth.UFP> wrote in 
message news:lov4ga$3v9$1@dont-email.me...
> On 2014-07-01, Dmitry A. Kazakov <mailbox@dmitry-kazakov.de> wrote:
>> On Tue, 1 Jul 2014 17:00:45 +0000 (UTC), Simon Clubley wrote:
>>> If for some reason the compiler could not generate a 32-bit str opcode
>>> instead of an 8-bit strb opcode, the pragma Atomic should have caused
>>> an error during compilation.
>>
>> Well, pragmas are permitted to be ignored. Atomic should never be a 
>> pragma.
>>
>
> I thought that only applied to unrecognised pragmas.

Correct. Pragma Atomic should be illegal if it is not supported.

But Dmitry is right, it should never have been a pragma. (Pragmas should 
only have been used for global configuration, never on individual entities, 
IMHO.)

> OTOH, going back a couple of versions to the Ada 95 RM (the version
> I have to hand and also the pragma only days), C.6(10) makes it clear
> that an Atomic pragma is illegal if the implementation cannot support
> the indivisible accesses required.

Right. If the OP really did exactly as he said, then GNAT has a bug (no 
matter what his declaration was). [But I've seen plenty of cases where 
someone (including me) thought they'd tried something when they really had 
not for one reason or another.]

                                    Randy.