Re: Experimenting with reduced gcc-lib

["Ludovic Courtès" <ludo@gnu.org>]

Hello!

Julien Lepiller <julien@lepiller.eu> skribis:

> Before the patch we get:
>
> guix size perl
> total: 147.7 MiB
>
> After the patch:
>
> ./pre-inst-env guix size perl
> total: 114.5 MiB

Nice!

> I don't want to push that patch as is, because libstdc++.so is still in
> the gcc-static-lib output and will bring all the useless stuff with it.
> C++ programs will bring back the remaining 33.2 MiB.

It wouldn’t be worse than the current situation though?

> Another possible target is glibc, since the only useful bits in there
> are libc.so and ld-linux.so (I think?). This could reduce the closure
> of our packs by another ~40 MiB (I think our systems would still need
> most of the content of this package).

‘share/i18n’ is 16 MiB and ‘lib/iconv’ is 8 MiB.  Now, separating them
without introducing loss of functionality may be tricky.

> From bff8567b0770455397d44f1ed304a67681b472c9 Mon Sep 17 00:00:00 2001
> From: Julien Lepiller <julien@lepiller.eu>
> Date: Thu, 8 Dec 2022 22:29:01 +0100
> Subject: [PATCH] gnu: gcc: Separate lib output.
>
> * gnu/packages/gcc.scm (gcc-4.7): Replace `lib' output with `static-lib'
>   and `shared-lib'.
> * gnu/packages/commencement.scm (gcc-boot0): Update accordingly.
> ---
>  gnu/packages/commencement.scm |  6 +++---
>  gnu/packages/gcc.scm          | 39 +++++++++++++++++++++++++----------
>  gnu/tests/mail.trs            |  0
>  3 files changed, 31 insertions(+), 14 deletions(-)
>  create mode 100644 gnu/tests/mail.trs

Oops?

>         (outputs '("out"                    ;commands, etc. (60+ MiB)
> -                  "lib"                    ;libgcc_s, libgomp, etc. (15+ MiB)
> +                  "shared-lib"             ;libgcc_s, libgomp, etc. (5+ MiB)
> +                  "static-lib"             ;object code libraries and internal data files of GCC. (10+ MiB)

The convention is to use “lib” for shared libraries and “static” for
static libraries.

Is libgomp in “lib”?  Is it found when linking with ‘-fopenmp’?

Thanks for this work; we really need to do something about package
sizes!

Ludo’.