On Wed, 23 Jan 2013 21:40:13 -0300
Alexis Ballier <aballier@gentoo.org> wrote:

> On Thu, 24 Jan 2013 00:23:57 +0100
> Michał Górny <mgorny@gentoo.org> wrote:
> 
> > This is mostly a proof-of-concept. If approved, I will work on moving
> > the code into a separate eclass, possibly named 'multilib-build' ;).
> > ---
> >  gx86/eclass/autotools-multilib.eclass | 24 +++++++++++++++++++++---
> >  1 file changed, 21 insertions(+), 3 deletions(-)
> > 
> > diff --git a/gx86/eclass/autotools-multilib.eclass
> > b/gx86/eclass/autotools-multilib.eclass index 7c8697a..eef7bcc 100644
> > --- a/gx86/eclass/autotools-multilib.eclass
> > +++ b/gx86/eclass/autotools-multilib.eclass
> > @@ -32,7 +32,23 @@ inherit autotools-utils multilib
> >  
> >  EXPORT_FUNCTIONS src_configure src_compile src_test src_install
> >  
> > -IUSE=multilib
> > +# Declare all of them, profiles will control their visibility.
> > +IUSE='abi_x86_32 abi_x86_64'
> > +
> > +# @FUNCTION: _autotools-multilib_get_enabled_abis
> > +# @DESCRIPTION:
> > +# Get the list of enabled ABIs. The returned names are suitable for
> > use +# with multilib.eclass.
> > +#
> > +# If multilib is not enabled or not supported, returns an empty list.
> > +
> > +	debug-print-function ${FUNCNAME} "${@}"
> > +
> > +	if use amd64; then
> > +		use abi_x86_64 && echo amd64
> > +		use abi_x86_32 && echo x86
> > +	fi
> > +}
> 
> I would rather iterate over a variable than hardcoding and duplicating
> it here:
> 
> MULTILIB_ABIS='abi_x86_32:x86 abi_x86_64:amd64'
> IUSE=""
> for i in $MULTILIB_ABIS ; do
>    IUSE+=" ${i%:*}"
> done
> 
> _autotools-multilib_get_enabled_abis() {
>    for i in $MULTILIB_ABIS ; do
>       use ${i%:*} && echo ${i#*:}
>    done
> }

What are the advantages? I feel like the explicit solution is much more
readable and obvious at the first glance.

> (maybe protect it with has_multilib_profile if you wish)    

Well, the current code assumes that no flags == non-multilib profile.

-- 
Best regards,
Michał Górny