[musl] Re: [Buildroot] [PATCH] package/cpulimit: Disable build on OpenRISC with musl-libc

[Stafford Horne <shorne@gmail.com>]

On Sat, May 14, 2022 at 07:14:21PM -0700, Florian Fainelli wrote:
> 
> 
> On 5/14/2022 7:09 PM, Stafford Horne wrote:
> > On Tue, May 10, 2022 at 05:19:47PM -0700, Florian Fainelli wrote:
> > > As reported in the following autobuild report:
> > > 
> > > http://autobuild.buildroot.net/results/2a9cf20949beac46d1c689df2c5b7ab0d59c08b5/
> > > 
> > > cpulimit does not build due to a lack of definition for elf_gregset_t
> > > which is not currently provided in the or1k musl-libc port. While this
> > > is being worked on, disable the build for or1k and musl-libc.
> > 
> > Hello,
> > 
> > You mention this is being worked on.  I am curious who is working on this?
> > 
> > I try to look over OpenRISC stuff, do you need me to do anything on musl for
> > this?
> 
> I posted this:
> 
> https://www.openwall.com/lists/musl/2022/05/10/1
> 
> if you don't mind reviewing, thanks!

No problem, I don't have the mail in my inbox, I've subscribed to musl now.

Put some comments below based on what I had configured in glibc.

    diff --git a/arch/or1k/bits/user.h b/arch/or1k/bits/user.h
    index e69de29bb2d1..3405bf771c0f 100644
    --- a/arch/or1k/bits/user.h
    +++ b/arch/or1k/bits/user.h
    @@ -0,0 +1,11 @@
    +struct user_regs {
    +	unsigned long gpr[32];
    +	unsigned long pc;
    +	unsigned long sr;
    +};

OK, matches glibc.

    +#define ELF_NGREG 34

In glibc we define this as 32.  Howerver, we define elf_gregset_t as
elf_gregset_t[34].  I don't see where ELF_NGREG is really used so I am
not sure of the impact to this.  I also can't remember why I set these
different in glibc.

    +typedef unsigned long elf_greg_t, elf_gregset_t[ELF_NGREG];
    +
    +/* or32 does not have floating point support, placeholder */
    +typedef unsigned long elf_fpregset_t;

OpenRISC uses the same registers and floating point and integer. This is defined
in glibc as:

/* Register set for the floating-point registers.  */
typedef elf_greg_t elf_fpregset_t[32];

-Stafford