That one last frontend feature to obsolete rebuild

[Gregor Richards]

Bill Baxter wrote:
> Gregor Richards wrote:
>> Believe it or not, I'd really like to obsolete rebuild. I'd love to 
>> have a tiny little script that just reads the output of [g]dmd -v and 
>> gets the list of files (and everything else) from that. At this point, 
>> I'm very close to being able to accomplish this feat, as the 
>> recent(ish) addition of outputting every file that's imported got my 
>> 90% of the way there, but there's one problem. rebuild supports 
>> nonstandard pragmas, and the compiler chokes on them.
>>
>> I would like to see a flag (-print-unsupported-pragmas or something 
>> else obscure, doesn't need to be short or simple) that changed the 
>> frontend's default behavior from choking on unrecognized pragmas to 
>> printing them out with the verbose output, e.g.:
>> pragma    link    "(argument to the pragma)"
>>
>> Clearly this wouldn't work for pragmas which wrap declarations, but 
>> for simple pragmas it would - and simple pragmas are all I need, and 
>> probably all that most frontend-extending tools would need. With this 
>> one, comparably simple change, I could scrap rebuild and write a 
>> simple script that would be incapable of becoming outdated. Heck, if 
>> you'd like, I could even write it and submit a patch :)
> 
> Sounds great to me.  I was pondering just the other day why Rebuild 
> hasn't switched to using the -v output rather than embedding the entire 
> DMD front end.  So pragmas are the only thing, huh?
> 
> One little thing -- I'd say just enhance -v output all pragmas.  No new 
> switch.  Tools that don't need them will just ignore them, tools which 
> do can grep for the ones they care about.
> 
> --bb

I don't quite agree, because IMHO dying on unrecognized pragmas is a 
good thing. e.g. I use some GCC property, then compile with DMD, and 
maybe I have to do something special since that pragma is unsupported. 
I'd rather have it tell me so I can go "d'oh! Needs version (GNU)" than 
just silently ignore it.

  - Gregor Richards