Re: [gentoo-devhelp] Building project twice in the same ebuild

[Michael Orlitzky <mjo@gentoo.org>]

On 02/15/2015 09:32 PM, Nikos Chantziaras wrote:
> I need to build a project (which uses cmake) twice and install it twice. 
> Each time with a different configuration. The files it generates in each 
> configuration do not conflict with each other (except for share/doc/).
> 
> Which configs are built depends on USE flags. Either qt4, qt5 or both.
> 
> How would I go on about this? The project's build system *can not* build 
> both sets in the same build. When building normally, outside of portage, 
> this is built with:
> 
>    mkdir build && cd build
>    cmake -DQT_VERSION=4 ../
>    make && make install
>    rm -r *
>    cmake -DQT_VERSION=5 ../
>    make && make install
> 
> I'm not sure I can do something like that in an ebuild.
> 

I would set S="${WORKDIR}" and then in src_prepare(), make a copy of the
entire package directory. The configure, compile, etc. phases would look
something like,

src_compile() {
	for qt in 4 5; do # Make this list from the user's USE flags
		cd "${WORKDIR}/${P}-qt${qt}" || die
		cmake -DQT_VERSION=${qt} || die
		emake
	done
}