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

From: Vladimir Prus (ghost_at_[hidden])
Date: 2007-12-06 14:58:51

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.

- Volodya