[PATCH, Fortran] Four small DEC extensions

[Jerry DeLisle]

On 10/12/2016 05:30 AM, Fritz Reese wrote:
> Here I submit for review four small extensions to the GNU Fortran
> frontend for compatibility with legacy code. I figure it might be a
> nice change of pace from my larger patches. Never fear, for I have
> more large patches to come, which I will continue to submit
> one-at-a-time.
>
> Each extension is enabled with its own compile flag, and each are
> enabled along with -fdec. They are fairly self-explanatory.
>
> 1. [-fdec-feed] Treat form feed characters as whitespace.

On form feed, my first thought is don't bother with the flag. Treating it as 
whitspace is no big deal.

> 2. [-fdec-type-print] Treat TYPE as an alias for PRINT where applicable.

On TYPE, I dont like the idea of supporting this since TYPE is a Fortran STD 
word, If it is just an alias, Run the source through SED or use cpp. If this 
seems so ownerous, then just put it behind -std=legacy, no need for new flag, 
just make sure -std=gnu or above gives error.

By the way, you may be thinking of -fdec-all that will grab all these dec 
extensions, or maybe just use one for all like -fdec and not have so many flags.

I wonder if we should add a flag called -floose-as-a-goose and just turn off all 
checks. ;)

> 3. [-fdec-loc-rval] Allow %LOC() as an rvalue, equivalent to using the
> LOC() intrinsic.

On  %LOC(), allow with -std=legacy or gnu, give an error for -std=fxxx, no need 
for new flag. This is another that could be cpp or sed fixed on source side.

> 4. [-fdec-logical-xor] Enable .XOR. as a logical operator.
>

On XOR, allow with -std=legacy or gnu, give an error for -std=fxxx, no need for 
new flag

> Feel free to comment on/question/approve each patch individually as
> desired. They are attached as sequential patch files for ease of
> review. Bootstraps & regtests on x86_64-redhat-
> linux. OK for trunk?
>

Not yet, generally, I don't think we need so many compiler flags. We should 
probably think about this as far as the other extensions you have already committed.

Jerry