[yocto] why do numerous .bb files set "PARALLEL_MAKE"?

[Richard Purdie]

On Fri, 2011-11-04 at 17:07 +0100, Martin Jansa wrote:
> On Fri, Nov 04, 2011 at 11:57:46AM -0400, Robert P. J. Day wrote:
> > 
> >   stumbled over this so i did a more thorough search:
> > 
> > $ grep -w PARALLEL_MAKE $(find . -name *.bb)
> > ./meta/recipes-qt/qt-apps/qmmp_0.5.1.bb:PARALLEL_MAKE = ""
> > ./meta/recipes-core/eggdbus/eggdbus_0.6.bb:PARALLEL_MAKE = ""
> > ./meta/recipes-core/gettext/gettext_0.16.1.bb:PARALLEL_MAKE = ""
> > ./meta/recipes-core/gettext/gettext_0.18.1.1.bb:#PARALLEL_MAKE = ""
> > ./meta/recipes-bsp/pciutils/pciutils_3.1.7.bb:PARALLEL_MAKE = ""
> > ./meta/recipes-extended/sat-solver/sat-solver_git.bb:PARALLEL_MAKE=""
> > ./meta/recipes-extended/bash/bash_3.2.48.bb:PARALLEL_MAKE = ""
> > ./meta/recipes-extended/tcp-wrappers/tcp-wrappers_7.6.bb:PARALLEL_MAKE = ""
> > ./meta/recipes-extended/groff/groff_1.20.1.bb:PARALLEL_MAKE = ""
> > ... more snipped ...
> > 
> >   why are individual recipes setting PARALLEL_MAKE to the empty
> > string?  it's a *build* option, why would it have any relevance to
> > individual .bb files?
> 
> because some projects fail to build in parallel and we don't have
> manpower to fix them all?

Just for reference we have actually fixed a lot of these in other
places, particularly where they're on the critical path. The situation
is a lot better than it ever used to be although obviously still room
for improvement!

Cheers,

Richard