[gentoo-soc] Progress: Gentoo RELIBC porting

[Ahmed Soliman]

Hello All,

So this is a quick recap of what has been done so far.
Between 25th July and a week ago I was in exams, but once I was done
there was huge progress.

So I was finally able to get gcc compile stage2 under gentoo using
relibc as "the" libc. Which means gcc is linked against relibc and it
produces a relibc binary. and that is (almost) full gcc. with support
for gcc plugins (specifically LTO plugin gave me hard time fixing bugs
in RTLD).

So at the end there was these two patches
https://gitlab.redox-os.org/redox-os/relibc/-/merge_requests/300
https://gitlab.redox-os.org/redox-os/relibc/-/merge_requests/303

The first allows RTLD to resolve bin paths using env $PATH and the
second introduces support for shared object soname and prevents
loading the same library twice. (half bug and half performance boost).

At this stage and after 10+ pull requests for that particular mile
stone gcc do work with relibc. (didn't I mention it uses relibc based
binutils as well? ).

Some patches fixed bugs in printf/scanf functions families, other
patches implemented missing header files, or implementing glibc(TM)
specific features in relibc. But, most of the patch sets I submitted
(as well as the time invested) are targeted towards RTLD, it proved to
be the most incomplete part in relibc and one of the hardest things to
work on.

The last real battle would be against the rust compiler if this gets
to compile and properly work, then the rest is just overlay repos and
simple stuff. (or I hope so).

Just in case someone might be interested in duplicating my work
environment, you are very much welcomed to the repo where I keep my
scripts for compiling stuff, when I started I thought I might forget
how I end up with working environment and now I don't even know the
./configure arguments I used for that very last recent gcc :P. Still
all is in the repo!
https://github.com/oddcoder/relibc-setup-repo

Thanks,
Ahmed.