On Fri, Mar 23, 2012 at 12:02 PM, Ciaran McCreesh
<ciaran.mccre...@googlemail.com> wrote:
> On Fri, 23 Mar 2012 11:58:47 -0400
> Mike Gilbert <flop...@gentoo.org> wrote:
>> > oasis_src_compile() {
>> > oasis_src_compile_no_doc
>> > if has doc ${IUSE} && use doc; then
>> > ocaml setup.ml -doc || die
>> > fi
>> > }
>>
>> This should probably call use_if_iuse from eutils.eclass, which
>> handles IUSE="[+-]doc".
>
> Actually, neither way works. The spec says:
>
> Global variables must only contain invariant values
> (see~\ref{sec:metadata-invariance}). If a global variable's value is
> invariant, it may have the value that would be generated at any
> given point in the build sequence.
>
> So you can't rely upon IUSE having the "merged" value in an eclass.
>
use_if_iuse is called from functions in several eclasses already in
the tree. See chromium, kde4-base, qt4-build, and toolchain.
Are all of these usages incorrect? Do you have an alternate solution?
