Re: [Boost-build] DLL <use> question

From: Phillip Seaver (phil_at_[hidden])
Date: 2006-09-16 15:33:47

Phillip Seaver wrote:
> Kevin Wheatley wrote, on 9/6/2006 5:04 AM:
>   
>> Phillip Seaver wrote:
>>   
>>     
>>> Any thoughts on this?  One of my co-workers worked around the problem by 
>>> doing a modules.poke of the requirements in the DLL build.jam and a 
>>> modules.peek in the exe build.jam, so they're still only defined in one 
>>> place, but I'd really like for this to work correctly.
>>>     
>>>       
>> you could create a requirements project, with a set of requirements 
>> specified, then use an alias in that project as a fake target, you 
>> would then referencwe that in the appropriate places...
>>
>> project c-dll
>>          : requirements
>>                  <link>shared
>>          : usage-requirements
>>                  <include>c
>>          ;
>>
>> lib c : c/c.cpp b :  : : <include>c ;
>>
>> # This allows us to pull a fake target to pick up the includes etc. 
>> for this project
>> alias usage-requirements ;
>>
>> Then something like this...
>>
>> lib a : a/a.cpp : <link>static : : <include>a ;
>> lib b : b/b.cpp a : <link>static : : <include>b ;
>> use-project /c-dll : c-dll ;
>> build-project c-dll ;
>> exe d : d.cpp : <library>/c-dll//usage-requirements <link>static ;
>>
>> Kevin
>>     
>
> That's a nicer work-around than the one we have now, but I think what I 
> was trying to do should work.  d has <use>c, which (correctly) does not 
> make d link against c or b, but for some reason, it links against a.
>
> Phillip

I've changed my build.jam files to use the work-around suggested by
Kevin, and it's much cleaner than the modules.poke/peek solution that we
were using, but I think the original problem is a bug.  d <use>'s c to
get the include paths from c, c has a and b statically linked into it,
but for some reason, a gets linked into d while b and c are not linked
into d.

Here's what my test case looked like:

    lib a : a/a.cpp : <link>static : : <include>a ;
    lib b : b/b.cpp a : <link>static : : <include>b ;
    lib c : c/c.cpp b : <link>shared : : <include>c ;
    exe d : d.cpp : <use>c <link>static ;

Phillip