Re: Interest in "Porting musl libc to RISC-V" project for GSoC 2016

[Szabolcs Nagy <nsz@port70.net>]

* Masanori Ogino <masanori.ogino@gmail.com> [2016-03-03 16:43:31 +0900]:
> I'm interested in porting musl to RISC-V arch project on
> http://www.lowrisc.org/docs/gsoc-2016-ideas/ . I have read guidelines
> for GSoC students and now I'm preparing to write up my proposal.
> 
> I'd like to ask you for your advice to understand technical details
> and improve my plan. Please let me know if you have any thoughts.
> Thank you.

last time iirc musl port was considered to be
not large enough in itself for a gsoc project
(i think it should not take more than 2 months
but i don't know the current state of risc-v
qemu/linux/gcc/etc)

you might need to think additional things to work on.

for musl, one idea is to invest extra time on testing.

for risc-v i think polishing the toolchain and the docs
would be useful.


there are some basic problems with the risc-v software
eco-system:

there is no proper sysv psabi spec. (designing one would
have been better than copying obsolete nonsense from mips
as i can see in the glibc port.)

nothing is upstream yet (gcc/linux/.. ports are
maintained out of tree, working with the upstream
community is important for many reasons).

risc-v mailing lists are not public, only subscribers
can see or participate in the discussions. (this is
bad given that there are no specs, no upstreamed code
so no source of information for outsiders.)

for a musl port this means that we don't have abi
stability guarantees, the port can stop working with
the rest of the risc-v software stack.   so for a
successful port i think some scripts should be developed
to build and test the latest risc-v things against musl
(cross-toolchain, rootfs, etc) so we can keep it working.