Re: [cxx-abi-dev] RE: [Cxx-abi] Re: [cxx-abi-dev] Question about guard variable typ es

[Jason Merrill <jason@xxxxxxxxxx>]

On Fri, 6 Dec 2002 09:52:08 -0800 , "Nelson, Clark" <clark.nelson@xxxxxxxxx> wrote:

>> It's a bit odd to require 64-bit types on all platforms; some may not
>> have them.  
>
> But of course C99 requires that long long have at least 64 bits. Are you
> concerned about the possibility that in some implementation long long might
> actually have, say, 128 bits? Or that some implementation that supports a
> type called long long may define it as having only 32 bits?
>
> Personally, I think the change you suggest is editorial, for all practical
> purposes. I'm just trying to understand how it might be substantive (and
> therefore require any change to G++ if it isn't made).

I think that the interesting question is forward-looking: on such a
hypothetical implementation with a 128-bit long long, do we want the guard
variable to be 64 or 128 bits?  Do we think we will need more space for
locking information on a larger architecture?

Jason