How do I get rid of LLVM?

Blind_Sniper · Guru Joined: 20 Apr 2018 Posts: 370

Hi.
Finally llvm-related software became the most bloated part of the system (apart from qt). As far as I understand llvm is just a kind of frontend to compilers, so I wondering, is it possible to get rid of this bloatware?
If there is useful info about it, please share
Thanks
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GNU is Not Usable

Hu · Administrator Joined: 06 Mar 2007 Posts: 22847

You can remove it just like anything else: emerge --ask --verbose --depclean sys-devel/llvm. If it is on your system, this will probably fail with a message about some package that needs it. Add that package to the depclean list and retry. Keep growing the list until either you find a package you're not willing to remove, or you get a successful run. In some cases, packages conditionally need it based on a USE flag. If that is your situation, disabling the USE flag (and rebuilding the affected package) may let you remove LLVM without removing the consuming package. This depends on whether the USE flag controls a feature you are not willing to remove.

My guess is that you will fail, as most modern graphical desktops want Mesa, and Mesa wants LLVM, at least in the common configurations. However, some less common configurations, and anything that can remove Mesa, may not be blocked here.

Blind_Sniper · Guru Joined: 20 Apr 2018 Posts: 370

Thanks ofr reply!

Hu · Administrator Joined: 06 Mar 2007 Posts: 22847

LLVM is not just a compiler. Look at the list of libraries it installs. Even if it were only a compiler, if your depclean has --with-bdeps=y, then Portage would retain packages that you would need if you chose to rebuild Mesa from source.

Blind_Sniper · Guru Joined: 20 Apr 2018 Posts: 370

At least switching to binary mesa prevented two new huge packages from being pulled in: llvm-runtimes/compiler-rt and llvm-runtimes/compiler-rt-sanitizers.
Not bad.
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GNU is Not Usable

Anon-E-moose · Posted: Wed Dec 18, 2024 4:22 pm Post subject:

a whole 57 meg ... impressive.
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UM780, 6.1 zen kernel, gcc 13, profile 17.0 (custom bare multilib), openrc, wayland

Blind_Sniper · Guru Joined: 20 Apr 2018 Posts: 370

Anon-E-moose · Posted: Wed Dec 18, 2024 5:19 pm Post subject:

Not to argue, but are you sure we're talking about the same packages?

Blind_Sniper · Guru Joined: 20 Apr 2018 Posts: 370

logrusx · Advocate Joined: 22 Feb 2018 Posts: 2518

bstaletic · Guru Joined: 05 Apr 2014 Posts: 407

jesnow · l33t Joined: 26 Apr 2006 Posts: 886

I have kind of accepted that we now have to have minimum two c/c++ compilers. But do we really have to have three slotted clangs? I don't even have a fancy system.

logrusx · Advocate Joined: 22 Feb 2018 Posts: 2518

You most definitely don't need clang:15.
What does emerge -pvc clang:15 say?
I bet you have it in world.

Best Regards,
Georgi

Anon-E-moose · Posted: Thu Dec 19, 2024 8:58 pm Post subject:

[IP-] [ ] llvm-core/clang-15.0.7-r3:15/15g1
[IP-] [ ] llvm-core/clang-18.1.8-r6:18/18.1

So what does "emerge -pvc llvm-core/clang-15.0.7-r3" return, same for 18.1
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UM780, 6.1 zen kernel, gcc 13, profile 17.0 (custom bare multilib), openrc, wayland

jesnow · l33t Joined: 26 Apr 2006 Posts: 886

GDH-gentoo · Posted: Fri Dec 20, 2024 2:32 am Post subject:

jesnow · l33t Joined: 26 Apr 2006 Posts: 886

The way I read this qttools hard requires 18 and everything requies qttools. So currently all my machines have to
recompile all of llvm twice. Thanks guys. some of the weaker machines my be at it for days.

Users should not be forced to have two massive C compilers on their system. But they *really* should not be forced to have three or four.

Aha: I *could* have masked off llvm/clang 19 as nothing seems to hard require it. Great.

logrusx · Advocate Joined: 22 Feb 2018 Posts: 2518

Hu · Administrator Joined: 06 Mar 2007 Posts: 22847

Since jesnow's complaint is a little unclear to me as to whom "Thanks guys" is addressing, I want to point out explicitly that Gentoo is generally limited to what upstream supports. Gentoo maintainers do not, as a general practice, create and maintain deeply invasive patches to the packages, so if upstream's qttools release only works with LLVM-18, that is what Gentoo's ebuilds will require. Unless you have specific evidence that upstream qttools has good support for LLVM-19 without serious adverse side effects to other packages on the system, please refrain from assuming the Gentoo maintainers are trying to make your life hard. I doubt they voluntarily create scenarios that force extra builds when they readily could avoid that.

sam_ · Developer Joined: 14 Aug 2020 Posts: 2028

I'll note again (as in other threads) that part of the point of the llvm-r1 eclass is to control this and not greedily pull in new slots so it's aligned to the default in profiles. Of course, sometimes software might only support an older or newer slot, and not the default one, but that's not the common case. It's hard to know what's happening for individual people here: ebuilds may still be using llvm.eclass (not everything is migrated yet, and possibly even from an overlay), or maybe the user has set custom LLVM_SLOT in /etc/portage.

(It's not clear to me if everyone in this thread even has the same problem, e.g. LLVM 19 being pulled in unnecessarily, or rather wanting everything off LLVM 18 right now, or something else). The default in eclasses is currently 19 as of about a week and a half a go, to coincide with LLVM 19 stabilisation. Some packages really don't support LLVM 19, though.

We dislike the LLVM ecosystem's issues as much as you do.

Ionen · Developer Joined: 06 Dec 2018 Posts: 2884