Re: [gentoo-dev] [PATCH] profiles/default/linux: Add USE="bzip2 lzma zstd" to defaults

[A Schenck]

On 7/8/21 11:15 AM, Matt Turner wrote:
> On Thu, Jul 8, 2021 at 4:54 AM Michael Orlitzky <mjo@g.o> wrote:
>> On Wed, 2021-07-07 at 22:01 -0700, Matt Turner wrote:
>>> Enable these flags by default, since they effectively add no additional
>>> dependencies:
>> Why? This list should be getting smaller, not larger.
>>
>> Polluting the base profiles makes running a minimal system that much
>> harder, and only "adds no dependencies" because people omit the
>> corresponding dependencies -- a situation that has to change
>> eventually.
>>
>> If they're actually important to a particular package, you should
>> change the defaults for that package.
> Not the file I'm changing, but I think the sentiment of the comment is
> correct: profiles/prefix/make.defaults says:
>
>   # Some USE-flags that only die-hards don't want:
>
> So, the thing about running a minimal system is... you already have
> these dependencies installed. This doesn't change that...
>
> I could of course change the default of every bzip2/lzma/zstd in IUSE
> (and might as well handle zlib too so we can remove it from
> make.defaults!) but what practical advantage does that bring?
>
> I doubt there's a sensible reason to build without any of these USE
> flags enabled. I think the claim that most people will want them
> enabled is not really a question. So we should enable them by default.
> I think that logic is pretty straightforward. If someone wants to
> disable the flags for some reason, they of course still have that
> option.

I recently found exactly a sensible reason to build without these
flags.  I was cleaning up my abi_x86_32 use flags on an otherwise mostly
x86_64 ~amd64 desktop system.  Lots of things depend on these with
${MULTILIB_USEDEP}.  I of course have the actual programs themselves,
but I don't need 32-bit versions of them for linking.  So I now have

```

a@gen5 ~/code $ grep "\-lzma" /etc/portage/package.use/*
/etc/portage/package.use/package.use:dev-libs/elfutils valgrind -lzma
-bzip2    #avoid multilib usedep on xz-utils and bzip2
/etc/portage/package.use/package.use:dev-libs/libxml2 -lzma -dbus      
#avoid multilib dep on xz-utils and dbus
a@gen5 ~/code $ grep "\-bzip" /etc/portage/package.use/*
/etc/portage/package.use/package.use:dev-libs/elfutils valgrind -lzma
-bzip2    #avoid multilib usedep on xz-utils and bzip2
/etc/portage/package.use/package.use:media-libs/freetype -bzip2 #avoid
multilib usedeps on bzip2 cairo requires [png]

```

in package.use.

>
> If you can find a case where you wouldn't want to enable one of these
> USE flags, please let me know and I'll reconsider my position.
>