Re: [PATCH] ppc: Include asm/ptrace.h for pt_regs struct definition

[Peter Maydell]

On Mon, 14 Mar 2022 at 17:22, Khem Raj <raj.khem@gmail.com> wrote:
>
> On Mon, Mar 14, 2022 at 10:05 AM Peter Maydell <peter.maydell@linaro.org> 
> wrote:
> >
> > On Mon, 14 Mar 2022 at 17:02, Khem Raj <raj.khem@gmail.com> wrote:
> > >
> > > Fixes
> > > ../qemu-6.2.0/linux-user/host/ppc64/../ppc/host-signal.h:16:32: error: 
> > > incomplete definition of type 'struct pt_regs'
> > >     return uc->uc_mcontext.regs->nip;
> > >            ~~~~~~~~~~~~~~~~~~~~^
> > >
> > > Signed-off-by: Khem Raj <raj.khem@gmail.com>
> > > Cc: Peter Maydell <peter.maydell@linaro.org>
> > > Cc: Philippe Mathieu-Daudé <f4bug@amsat.org>
> > > Cc: Richard Henderson <richard.henderson@linaro.org>
> > > ---
> > >  linux-user/include/host/ppc/host-signal.h | 4 ++++
> > >  1 file changed, 4 insertions(+)
> > >
> > > diff --git a/linux-user/include/host/ppc/host-signal.h 
> > > b/linux-user/include/host/ppc/host-signal.h
> > > index b80384d135..43ee2eee3b 100644
> > > --- a/linux-user/include/host/ppc/host-signal.h
> > > +++ b/linux-user/include/host/ppc/host-signal.h
> > > @@ -11,6 +11,10 @@
> > >  #ifndef PPC_HOST_SIGNAL_H
> > >  #define PPC_HOST_SIGNAL_H
> > >
> > > +#if defined(__powerpc__)
> >
> > Why is this #if defined() needed ?
>
> yeah the define is redundant. I will send a v2
>
> >
> > > +#include <asm/ptrace.h>
> > > +#endif
> >
> > What host distro are you building with? We do test ppc64be at least
> > in our CI, and that builds OK.
>
> I have a custom distro building with Yocto which is using musl C
> library instead of glibc.

Ah, musl. I found this gcc mailing list post from one of the musl
upstream developers:
https://www.mail-archive.com/gcc-patches@gcc.gnu.org/msg281012.html

where he suggests a different approach involving uc_regs->gregs[32]
for ppc32 and uc_mcontext.gp_regs[32] for ppc64.

Richard: any opinion on that idea ?

-- PMM