[gentoo-soc] Weekly Progress Report: Porting Relibc to gentoo

[Ahmed Soliman]

Hello,

For past (few) week(s): I have been working on compiling Gcc with relibc,

I have faced bunch of bugs and missing features and bugs,

First about setting up the environment and my previous work on the
task, I had documented it in a public blog post so I will just like it
to it here[1].

As for GCC, the first issue I faced was that it was expecting types
that was not defined in relibc and it has been fixed in this merge
request[2]

Next issue was bug[3] that was revealed by GCC was well but related to
LD_SEARCH_PATH variable. The issue was that it was using errno which
is Thread Local variable even though thread local memory was not
setted up yet.

Third issue[4] was related to gcc using -fpermessive and that didn't
play well with some macros defined in include/bits/limits.h .

The last issue[5] which is the most complex by far was that *scanf*
functions required lookahead but they never seek back after the
lookahead, The problem was that at their core they all were dealing
with a rust Reader object which doesn't support seek back at all. So
my solution was designing a new wrapper for both Files and Buffers
that supports reading as well as looking ahead.

[1] https://oddcoder.com/GSOC-with-gentoo/
[2] https://gitlab.redox-os.org/redox-os/relibc/-/merge_requests/270
[3] https://gitlab.redox-os.org/redox-os/relibc/-/merge_requests/275
[4] https://gitlab.redox-os.org/redox-os/relibc/-/merge_requests/276
[5] https://gitlab.redox-os.org/redox-os/relibc/-/merge_requests/277