Re: [musl] [PATCH] mips: use `jr $ra` instead of `j $ra` to work around an LLVM assembler bug

["Alex Rønne Petersen" <alex@alexrp.com>]

On Wed, Oct 23, 2024 at 12:58 AM Rich Felker <dalias@libc.org> wrote:
>
> On Wed, Sep 18, 2024 at 03:18:42AM +0200, Alex Rønne Petersen wrote:
> > Details here: https://github.com/llvm/llvm-project/issues/107460
> >
> > This patch works around the bug by just using the `jr $ra` form, which also more
> > precisely indicates the encoding intent anyway.
> > ---
> >  crt/mips/crtn.s   | 4 ++--
> >  crt/mips64/crtn.s | 4 ++--
> >  2 files changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/crt/mips/crtn.s b/crt/mips/crtn.s
> > index 506a04b7..92eb3d0e 100644
> > --- a/crt/mips/crtn.s
> > +++ b/crt/mips/crtn.s
> > @@ -3,11 +3,11 @@
> >  .section .init
> >       lw $gp,24($sp)
> >       lw $ra,28($sp)
> > -     j $ra
> > +     jr $ra
> >       addu $sp,$sp,32
> >
> >  .section .fini
> >       lw $gp,24($sp)
> >       lw $ra,28($sp)
> > -     j $ra
> > +     jr $ra
> >       addu $sp,$sp,32
> > diff --git a/crt/mips64/crtn.s b/crt/mips64/crtn.s
> > index f3930b24..8f090ed3 100644
> > --- a/crt/mips64/crtn.s
> > +++ b/crt/mips64/crtn.s
> > @@ -3,11 +3,11 @@
> >  .section .init
> >       ld $gp,16($sp)
> >       ld $ra,24($sp)
> > -     j $ra
> > +     jr $ra
> >       daddu $sp,$sp,32
> >
> >  .section .fini
> >       ld $gp,16($sp)
> >       ld $ra,24($sp)
> > -     j $ra
> > +     jr $ra
> >       daddu $sp,$sp,32
> > --
> > 2.40.1
>
> Thanks. Applying this with the same applied to mipsn32 too.

Oops, I'd completely forgotten to apply it there because we hadn't yet
imported musl's mipsn32 code in Zig. Thanks!