Re: [jamboost] Re: [BBv2] fix for response file regeneration

From: Zbynek Winkler (zw-bjam_at_[hidden])
Date: 2005-10-24 04:45:28

Reece Dunn wrote:

>Zbynek Winkler <zw-bjam <at> robotika.cz> writes:
> 
>
>>Reece Dunn wrote:
>>
>> 
>>
>>>If you, Volodya or anyone else has a better solution feel free to add it 
>>>to the discussion.
>>>
>>> 
>>>
>>The response files are "just a workaround" for a limited command line 
>>length, right?
>> 
>>
>
>Yes. They allow you to pass defines and include directories that would go beyond
>the command line limit.
>
> 
>
>>If this is true, would it be worth to consider just creating the 
>>response file in the action? I mean that the response file would not be 
>>a target at all, the build engine would never see it... The information 
>>to create the rsp is already there and it would have the right semantic 
>>(recreate the rsp each time the target is rebuild) and we could easily 
>>keep the rsps around...
>> 
>>
>
>The problem is that the response file generation logic is currently tied into the
>rule+action architecture, so removing them as a target would (currently) break
>this. I am unsure how tightly they are bound to this arcitecture, so don't know
>the impact of removing them as a target.
>
>Another thing is that the response file is placed in the debug/gcc, etc. build
>directory, but this can be worked around by using $(>[1]).rsp.
>
>Your idea seems sound in theory, I would need some time to work on the
>implementation as I only have a limited knowledge of how response files work.
> 
>
My knowledge is also limited ;-). But I think that with this approach 
the msvc toolset could very much look like some other toolset that does 
not use rcp (ie. gcc). The only thing that would differ IMHO would the 
be the actions, so instead of building a really long command line of all 
the options and calling the compiler with it, it would somehow process 
them into a file of our choosing (while not running into the command 
line length limitations - but maybe this is why a new builtin might be 
needed? I don't know.) and reference this file in the final build command.

HTH,
Zbynek

-- 
http://zw.matfyz.cz/ http://robotika.cz/
Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic