Can't share build trees?

[Gary Thomas <gary@mlbassoc.com>]

I have a system which has both PowerPC and ARM/OMAP components.
They share a common Poky/Yocto layer, so I thought I'd be able
to also share a build tree.  So, I tried something like this:
   % . /opt/poky/oe-init-build-env my_target
   % MACHINE=MY_OMAP bitbake omap-image
   % MACHINE=MY_PPC bitbake ppc-image

All seemed fine the first time through.  The images were built
as expected and worked well.

Sadly, when I tried to build something else, e.g.
   % MACHINE=MY_OMAP bitbake some-package
it set off rebuilding the entire cross tool chain :-(

Should this work?  or should I just be aware it does not (and mostly
tell my customers not to expect it to work)?

Thanks

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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