On Tue, Mar 16, 2021 at 5:28 PM Richard W.M. Jones <rjones@xxxxxxxxxx> wrote: > > On Mon, Mar 15, 2021 at 11:24:47AM +0100, Florian Weimer wrote: > > * Takayuki Nagata: > > > > > I think "--with-arch=" should be "rv64g" for gcc without compressed > > > instruction support, because the default is RV64GC[0]. > > > > As far as I understand it, there is no glibc port for RISC-V without > > compressed instruction support. Presumably the GCC default reflects > > this. > > Oh ah, is this so? If so that's a problem for Billa because > he's trying to rebuild Fedora for the SHAKTI chip that lacks > compressed instructions. > > But I had a look through all the RISC-V asm files in current glibc and > I can't see any compressed instructions there, nor any directives to > turn on the rvc option. > > $ egrep -i '(\bc\.|rvc)' `find sysdeps/riscv/ sysdeps/unix/sysv/linux/riscv/ -name '*.S' ` > > Do you know why glibc wouldn't understand the C extension? > Note, that Linux kinda requires C too now (since EFI was merged). See: https://lists.infradead.org/pipermail/linux-riscv/2021-March/004961.html Quote from Palmer's reply: """ So the dependency here is actually a bit odd: platforms without C _can_ use EFI, the EFI images just can't be booted on non-EFI systems (because the flat binaries need to execute the PE/COFF header). The issue is really that we can't support all three of non-C, EFI, and non-EFI in the Image format. The reason we coupled C and EFI is really to avoid the existence of EFI-only kernels, which are a headache these days because EFI isn't widely supported or used on RISC-V. The general assumption is that, since we recommend rv64gc for portable systems and EFI is mostly of interest to portable systems, we won't end up with non-C EFI systems and therefor don't need to worry about having incompatible kernels. That said, if there's one thing I've learned from the whole RISC-V thing it's that whenever I say "we don't think hardware that does X will show up" it does. Assuming that's the case and we end up with non-C systems that people want to run EFI on, we'll figure out a way to do that -- if someone has real hardware I'm inclined to support it, otherwise we just end up with a mess of vendor-specific forks. """ _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
