Re: [gentoo-dev] [rfc] dev-libs/expat[unicode] and dev-libs/libbsd dependency

[Michał Górny]

On śro, 2017-05-31 at 14:19 +0200, Sebastian Pipping wrote:
> Hi!
>
>
> The next release of dev-libs/expat is not far away and there are two
> things that I would appreciate input with, before the next bump in Gentoo:
>
>
> -DXML_UNICODE_WCHAR_T issues and Gentoo/Debian mismatch
> =======================================================
>
> With USE=unicode, on Gentoo two extra libraries are built:
>
>  * libexpatu.so (with CPPFLAGS=-DXML_UNICODE)
>  * libexpatw.so (with CPPFLAGS=-DXML_UNICODE_WCHAR_T)
>            ^
> However, -DXML_UNICODE_WCHAR_T has only ever worked with 2-byte wchar_t,
> while 4-byte wchar_t seems mainstream on Linux (and GCC -fshort-wchar
> would required libc to have the same, if you actually wanted to pass
> those wchar_t strings to wprintf and friends).
>
> So libexpatw.so in Gentoo is not functional at the moment.
>
> To make things worse, Debian has libexpatw.so with
> CPPFLAGS=-DXML_UNICODE, which corresponds to current libexpatu.so in
> Gentoo, rather than libexpatw.so.
>
>
> How do you evaluate these options:
>
>  a) Keep libexpatu.so + change libexpatw.so to CPPFLAGS=-DXML_UNICODE
>
>  b) Drop libexpatu.so + change libexpatw.so to CPPFLAGS=-DXML_UNICODE

Does any other distribution use libexpatu.so? If not, then there's
probably no point in keeping it.

>
>
> Depend on dev-libs/libbsd
> =========================
>
> The next release is very likely to add (optional but helpful) support
> for arc4random_buf that dev-libs/libbsd provides (especially on systems
> with glibc prior to 2.25) [1].  I wonder if Expat's proximity to @system
> has any strong implications on whether
>
>  A) libbsd should be a default-off use dependency
>       IUSE="libbsd"  RDEPEND="libbsd? ( dev-libs/libbsd )"
>
>  B) libbsd could be a default-on use dependency
>       IUSE="+libbsd"  RDEPEND="libbsd? ( dev-libs/libbsd )"

I'd dare say the feature is 'arc4random', then that should be the name
of the flag.

>  C) libbsd could even go into DEPEND and RDEPEND directly, or
>       RDEPEND="dev-libs/libbsd"
>
>  D) libbsd should not become any kind of future dependency of
>     dev-libs/expat.
>

-- 
Best regards,
Michał Górny