Re: [Boost-build] Propagated feature that doesn't generate build directory

From: K. Noel Belcourt (kbelco_at_[hidden])
Date: 2007-12-07 18:22:08

On Dec 6, 2007, at 11:00 PM, Vladimir Prus wrote:

> K. Noel Belcourt wrote:
>
>> On Dec 6, 2007, at 12:58 PM, Vladimir Prus wrote:
>>
>>> K. Noel Belcourt wrote:
>>>
>>>> On Dec 5, 2007, at 11:03 PM, Rene Rivera wrote:
>>>>
>>>>> K. Noel Belcourt wrote:
>>>>>> feature lapack : vendor source : propagated ;
>>>>>>
>>>>>> When I run bjam, I can select either lapack=vendor or  
>>>>>> lapack=source
>>>>>> and everything works fine.  The only problem is that because the
>>>>>> lapack feature is propagated, an entire new source tree (with
>>>>>> lapack-
>>>>>> source) is created when all I really want is to build one library
>>>>>> from source and link it in (i.e. the lapack library doesn't
>>>>>> introduce
>>>>>> any kind of link incompatibility).  Removing the propagated
>>>>>> attribute
>>>>>> clearly won't build the lapack library from source code.
>>>>>>
>>>>>> Is there another (combination of) attribute(s) that would  
>>>>>> propagate
>>>>>> the lapack=source feature to all targets, but not cause any new
>>>>>> directories in the build tree?
>>>>>
>>>>> Make it "incidental"
>>>>> <http://beta.boost.org/doc/tools/build/doc/html/bbv2/reference/
>>>>> definitions.html#bbv2.reference.features.attributes>.
>>>>
>>>> Hi Rene,
>>>>
>>>> When I tried changing the lapack feature to be incidental, it  
>>>> did not
>>>> work (the documentation says "incidental features are assumed  
>>>> not to
>>>> affect build properties").  The lapack=source feature is not  
>>>> present
>>>> in the property-set for the lapack product.
>>>>
>>>> Any other ideas?
>>>
>>> Well, I think the feature should be *both* propagated and  
>>> incidental.
>>
>> Well this ( feature lapack : vendor source : propagated
>> incidental ; ) doesn't work either.  It never builds the lapack
>> library from source code.  If this should work, then perhaps it's a
>> bug?  Would it help if I made a small example problem that you could
>> test for yourself.
>
> Yes, it would help.

Okay, a simple test case is attached.  Please let me know if there's  
anything else you need.

-- Noel