Desire to allocate bit in DT_PARM bitmask for DEC FORMAT compatibility purposes

[Jeff Law]

On 03/26/2018 01:15 PM, Steve Kargl wrote:
> On Mon, Mar 26, 2018 at 09:42:40AM +0200, Jakub Jelinek wrote:
>> On Sun, Mar 25, 2018 at 08:44:41PM -0700, Steve Kargl wrote:
>>> Now that you mention it, -std=dec would prevent a user from
>>> specifically requesting, say, only Fortran 95 with DEC
>>> extensions (i.e, -std=f95 -fdec).
>>>
>>> So, to prevent a bikeshed and micro-engineering, I think you
>>> should go with using bit 28 to comunicate with the runtime
>>> and put everything under -fdec in the FE.
>>
>> In that case, we would have two bits that are always set based on flag_dec
>> in the compiler.
>>
>> Thus, wouldn't following patch be better?  I.e. just rename the existing bit
>> from a single particular DEC extension to indicate it turns on all runtime
>> DEC extensions we support, now or in the future?
>>
>> Is this ok for trunk now (if it passes bootstrap/regtest)?  Jeff then can
>> follow with his patch in stage1 just using this bit.
>>
> 
> Jakub,
> 
> I'll going to be traveling for meetings over he next
> week, so will only have limited time and email access.
> I will defer to Jerry as he is much more familiar with
> the runtime library IO routines.
Happy to go with whatever Jerry decides.

Thanks,

jeff